ML062760008

to Hydrogeologic Investigation Report, Fleetwide Assessment, LaSalle Generating Station.

ML062760008
Person / Time
Site:	LaSalle
Issue date:	09/30/2006
From:	Conestoga-Rovers & Associates
To:	Exelon Generation Co, Office of Nuclear Reactor Regulation
References
045136 (16), FOIA/PA-2010-0209
Download: ML062760008 (613)

Text

Revision 1 Certain figures in this Report contain sensitive, security-related information protected from public disclosure by Federal and State law. This Report is suitable for public disclosure only after these figures are removed.

HYDROGEOLOGIC INVESTIGATION REPORT FLEETWIDE ASSESSMENT LaSALLE GENERATING STATION MARSEILLES, ILLINOIS Prepared For:

Exelon Generation Company, LLC DISCLAIMER: Prepared by:

SOME FORMATTING CHANGES MAY HAVE OCCURRED WHEN THE ORIGINAL DOCUMENT WAS PRINTED TO PDF; HOWEVER, Conestoga-Rovers THE ORIGINAL CONTENT REMAINS UNCHANGED. & Associates 651 Colby Drive Waterloo, Ontario Canada N2V 1C2 Office: (519) 884-0510 Fax: (519) 884-0525 SEPTEMBER 2006 web: http:\\www.CRAworld.com REF. NO. 045136 (16)

Worldwide Engineering, Environmental, Construction, and IT Services

Revision 1 TABLE OF CONTENTS Page EXECUTIVE

SUMMARY

.................................................................................................................... i

1.0 INTRODUCTION

...................................................................................................................1 2.0 STATION DESCRIPTION .....................................................................................................2 2.1 STATION LOCATION .......................................................................................2 2.2 OVERVIEW OF COOLING WATER OPERATIONS.....................................2 2.3 SURROUNDING LAND USE ...........................................................................4 2.4 STATION SETTING............................................................................................4 2.4.1 TOPOGRAPHY AND SURFACE WATER FEATURES.................................4 2.4.2 GEOLOGY ............................................................................................................6 2.4.3 HYDROGEOLOGY .............................................................................................6 2.5 AREA GROUNDWATER USE ..........................................................................8 3.0 AREAS FOR FURTHER EVALUATION...........................................................................10 3.1 SYSTEMS EVALUATIONS..............................................................................10 3.2 HISTORICAL RELEASES ................................................................................13 3.3 STATION INVESTIGATIONS.........................................................................13 3.3.1 PRE-OPERATIONAL RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM.............................................................................13 3.3.2 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM .........................................................................................................15 3.3.3 HISTORIC INVESTIGATIONS .......................................................................15 3.3.3.1 POWER PLANT DOCUMENTS-UFSAR REPORT ......................................16 3.3.3.2 GROUNDWATER TRITIUM MONITORING PROGRAM.........................16 3.3.3.3 BLOWDOWN LINE INVESTIGATION.........................................................17 3.4 IDENTIFIED AREAS FOR FURTHER EVALUATION ...............................17 4.0 FIELD METHODS.................................................................................................................20 4.1 STAFF GAUGES INSTALLATION ................................................................20 4.2 GROUNDWATER MONITORING WELL INSTALLATION.....................20 4.3 GROUNDWATER MONITORING WELL DEVELOPMENT ....................22 4.4 SURVEY ..............................................................................................................23 4.5 GROUNDWATER AND SURFACE WATER ELEVATION MEASUREMENTS ............................................................................................23 4.6 GROUNDWATER AND SURFACE WATER SAMPLE COLLECTION ..................................................................................24 4.7 DATA QUALITY OBJECTIVES.......................................................................26 4.8 SAMPLE IDENTIFICATION ...........................................................................26 4.9 CHAIN-OF-CUSTODY RECORD...................................................................27 4.10 QUALITY CONTROL SAMPLES ...................................................................27 4.11 ANALYSES.........................................................................................................28 045136 (16) LaSalle Generating Station CONESTOGA-ROVERS & ASSOCIATES

Revision 1 TABLE OF CONTENTS Page 4.12 ADDITIONAL FIELD ACTIVITIES................................................................28 4.12.1 WELL INVENTORY .........................................................................................28 4.12.2 TEMPORARY SAMPLING POINT INSTALLATION .................................28 4.12.3 TEMPORARY SAMPLING POINT SAMPLE COLLECTION....................29 5.0 RESULTS

SUMMARY

..........................................................................................................30 5.1 STATION GEOLOGY .......................................................................................30 5.2 STATION HYDROGEOLOGY ........................................................................32 5.2.1 GROUNDWATER FLOW DIRECTIONS ......................................................33 5.2.2 MAN-MADE INFLUENCES ON GROUNDWATER FLOW .....................34 5.3 GROUNDWATER QUALITY..........................................................................35 5.3.1

SUMMARY

OF BETA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS.................................................................................36 5.3.2

SUMMARY

OF GAMMA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS.................................................................................36 5.3.3

SUMMARY

OF FIELD MEASUREMENTS ...................................................37 5.4 SURFACE WATER QUALITY.........................................................................37 5.4.1

SUMMARY

OF BETA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS.................................................................................37 5.4.2

SUMMARY

OF GAMMA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS.................................................................................38 6.0 RADIONUCLIDES OF CONCERN AND SOURCE AREAS .........................................39 6.1 GAMMA-EMITTING RADIONUCLIDES.....................................................39 6.2 BETA-EMITTING RADIONUCLIDES ...........................................................39 6.3 TRITIUM.............................................................................................................39 6.3.1 GENERAL CHARACTERISTICS ....................................................................39 6.3.2 DISTRIBUTION IN STATION GROUNDWATER.......................................40 6.3.3 DISTRIBUTION IN STATION SURFACE WATER......................................41 6.3.4 CONCEPTUAL MODEL OF TRITIUM RELEASE AND MIGRATION ...........................................................................................41 7.0 EXPOSURE PATHWAY ASSESSMENT............................................................................45 7.1 HEALTH EFFECTS OF TRITIUM...................................................................45

7.2 BACKGROUND

CONCENTRATIONS OF TRITIUM ................................46 7.2.1 GROUNDWATER.............................................................................................46 7.2.2 PRECIPITATION DATA ..................................................................................46 7.2.3 SURFACE WATER DATA ...............................................................................47 7.2.4 DRINKING WATER DATA ............................................................................48 7.2.5 EXPECTED TRITIUM BACKGROUND FOR THE STATION ...................49 045136 (16) LaSalle Generating Station CONESTOGA-ROVERS & ASSOCIATES

Revision 1 TABLE OF CONTENTS Page 7.3 IDENTIFICATION OF POTENTIAL EXPOSURE PATHWAYS AND POTENTIAL RECEPTORS ............................................50 7.3.1 POTENTIAL GROUNDWATER MIGRATION TO DRINKING WATER USERS AT THE STATION ...............................................................50 7.3.2 POTENTIAL GROUNDWATER MIGRATION TO DRINKING WATER USERS OFF THE STATION PROPERTY .......................................51 7.3.3 POTENTIAL GROUNDWATER MIGRATION TO SURFACE WATER USERS..................................................................................................51 7.4

SUMMARY

OF TRITIUM EXPOSURE PATHWAYS ..................................52 7.5 OTHER RADIONUCLIDES.............................................................................52

8.0 CONCLUSION

S....................................................................................................................53 9.0 RECOMMENDATIONS.......................................................................................................59 9.1 DATA GAPS ......................................................................................................59 9.2 GROUNDWATER MONITORING ................................................................59

10.0 REFERENCES

CITED...........................................................................................................60 045136 (16) LaSalle Generating Station CONESTOGA-ROVERS & ASSOCIATES

Revision 1 LIST OF FIGURES (Following Text)

FIGURE 1.1 STATION LOCATION MAP FIGURE 1.2 STATION BOUNDARIES AND FEATURES FIGURE 2.1 REGIONAL GEOLOGIC CROSS-SECTION A-A' AND B-B' FIGURE 2.2 GEOLOGIC CROSS-SECTION - STATION TO ILLINOIS RIVER FIGURE 2.3 SITE STRATIGRAPHIC UNITS AND CHARACTERISTICS FIGURE 2.4 AREA WATER SUPPLY WELLS FIGURE 3.1 AREAS FOR FURTHER EVALUATION (STATION)

FIGURE 3.2 AREAS FOR FURTHER EVALUATION (PROTECTED AREA)

FIGURE 4.1 GROUNDWATER AND SURFACE WATER MONITORING LOCATIONS FIGURE 5.1 HYDROGEOLOGIC CROSS-SECTION LOCATIONS FIGURE 5.2 HYDROGEOLOGIC CROSS-SECTION A-A' FIGURE 5.3 HYDROGEOLOGIC CROSS-SECTION B-B' FIGURE 5.4 HYDROGEOLOGIC CROSS-SECTION C-C' FIGURE 5.5 POTENTIOMETRIC SURFACE CONTOURS - JULY 2006 FIGURE 5.6 TOP OF CLAY CONTOURS FIGURE 5.7 GROUNDWATER SATURATED THICKNESS - MAY 2006 FIGURE 5.8 TRITIUM CONCENTRATIONS - GROUNDWATER AND SURFACE WATER FIGURE 5.9 RADIONUCLIDE CONCENTRATION - GROUNDWATER AND SURFACE WATER 045136 (16) LaSalle Generating Station CONESTOGA-ROVERS & ASSOCIATES

Revision 1 LIST OF TABLES (Following Text)

TABLE 4.1

SUMMARY

OF MONITORING WELL INSTALLATION DETAILS TABLE 4.2

SUMMARY

OF MONITORING WELL DEVELOPMENT PARAMETERS TABLE 4.3

SUMMARY

OF GROUNDWATER ELEVATIONS TABLE 4.4

SUMMARY

OF SURFACE WATER ELEVATIONS TABLE 4.5 SAMPLE KEY TABLE 4.6

SUMMARY

OF MONITORING WELL PURGING PARAMETERS TABLE 5.1 ANALYTICAL RESULTS

SUMMARY

- TRITIUM IN GROUNDWATER TABLE 5.2 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER TABLE 5.3 ANALYTICAL RESULTS

SUMMARY

- TRITIUM IN SURFACE WATER TABLE 5.4 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN SURFACE WATER 045136 (16) LaSalle Generating Station CONESTOGA-ROVERS & ASSOCIATES

Revision 1 LIST OF APPENDICES APPENDIX A WATER WELL DATABASE SEARCH INFORMATION APPENDIX B MONITORING WELL STRATIGRAPHIC AND INSTRUMENTATION LOGS APPENDIX C QUALITY ASSURANCE PROGRAM - TELEDYNE BROWN ENGINEERING, INC.

APPENDIX D LABORATORY ANALYTICAL REPORTS APPENDIX E DATA VALIDATION MEMORANDUM 045136 (16) LaSalle Generating Station CONESTOGA-ROVERS & ASSOCIATES

Revision 1 EXECUTIVE

SUMMARY

This Hydrogeologic Investigation Report (HIR) documents the results of Conestoga-Rovers & Associates' (CRA's) May 2006 Hydrogeologic Investigation Work Plan (Work Plan) pertaining to the LaSalle County Station. CRA prepared this Hydrogeologic Investigation Report for Exelon Generation Company, LLC (Exelon) as part of its Fleetwide Program to determine whether groundwater at and in the vicinity of its nuclear power generating facilities has been adversely impacted by any releases of radionuclides.

CRA collected and analyzed information on historical releases, the structures, components, and areas of the Station that have the potential to release tritium or other radioactive liquids to the environment and past hydrogeologic investigations at the Station. CRA used this information, combined with its understanding of groundwater flow at the Station to identify the Areas for Further Evaluation (AFEs) and sample locations for the Station.

CRA installed 13 new monitoring wells and five temporary sample points. CRA collected 20 groundwater samples and six surface water samples at the Station. CRA also collected a full round of water levels from the newly installed and existing wells and measured surface water levels. All groundwater and surface water samples were analyzed for tritium, strontium-89/90, and gamma-emitting radionuclides.

The results of the hydrogeologic investigation are as follows:

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective Lower Limits of Detection (LLDs) in any of the groundwater or surface water samples obtained and analyzed during the course of this investigation;

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 picoCuries per liter (pCi/L) in any of the groundwater or surface water samples obtained and analyzed during the course of this investigation;

• Tritium was not detected at concentrations greater than the United States Environmental Protection Agency drinking water standard of 20,000 pCi/L in any of the groundwater or surface water samples obtained during the course of this investigation;

• Low levels of tritium were detected at concentrations greater than the LLD of 200 pCi/L, which is considered background, but well below the applicable drinking water standard; 045136 (16) LaSalle Generating Station i CONESTOGA-ROVERS & ASSOCIATES

Revision 1

• Tritium was detected in a sample from one groundwater monitoring well (MW-LS-105S at 1,280 +/- 184 pCi/L). The presence of tritium at this location was verified through re-sampling. Tritium was detected in the second groundwater sample from MW-LS-105S at 766 +/- 153 pCi/L. The source of tritium in monitoring well MW-LS-105S is most likely from a historical release associated with the Cycled Condensate Storage Tank overflow in 2001. Samples obtained from adjacent monitoring wells and surface water locations revealed no detectable tritium levels.

The tritium detected in MW-LS-105S is localized to the area of that well;

• Tritium was also detected in two surface water samples (SW-LS-101 and SW-LS-106 at 232 +/- 116 pCi/L and 219 +/- 113 pCi/L, respectively). SW-LS-106 was collected from the Intake Canal and SW-LS-101 was collected from the north storm water retention pond. The remaining surface water locations have tritium concentrations of less than the lower limit of detection (200 pCi/L). These detections are likely due to background surface water concentrations, since the Station pumps over 80 million gallons per day of Illinois River water into LaSalle Lake (surface water concentrations from the Illinois River range from non-detect at the lower limit of detection of 200 pCi/L to a high of 1,682 pCi/L);

• Based on the results of this investigation, tritium is not migrating off the Station property at detectable concentrations;

• Based on the results of this investigation, there is no current risk from exposure to radionuclides associated with licensed plant operations through any of the identified potential exposure pathways; and

• Based on the results of this investigation, there are no known active releases into the groundwater at the Station.

Based upon the information collected to date, CRA recommends that Exelon conduct periodic monitoring of selected sample locations.

045136 (16) LaSalle Generating Station ii CONESTOGA-ROVERS & ASSOCIATES

Revision 1

1.0 INTRODUCTION

Conestoga-Rovers and Associates (CRA) prepared this Hydrogeologic Investigation Report (HIR) for Exelon Generation Company, LLC (Exelon) as part of its Fleetwide Program to determine whether groundwater at and near its nuclear power generating facilities has been adversely impacted by any release of radionuclides. This report documents the results of CRA's May 2006 Hydrogeologic Investigation Work Plan (Work Plan) as well as an additional investigative task recommended by CRA during the course of the investigation. These investigations pertain to Exelon's LaSalle County Generating Station (Station) in Marseilles, Illinois (see Figure 1.1). The Station is defined as all property, structures, systems, and components owned and operated by Exelon, LLC located at 2601 North 21st Road in rural Brookfield Township, LaSalle County, Marseilles, Illinois. The approximate property boundaries are depicted on Figure 1.2.

Pursuant to the Work Plan, CRA assessed groundwater quality at the Station in locations designated as Areas for Further Evaluation (AFEs). The process by which CRA identified AFEs is discussed in Section 3.0 of this report.

The objectives of the Work Plan were to:

• characterize the geologic and hydrogeologic conditions at the Station including subsurface soil types, the presence or absence of confining layers, and the direction and rate of groundwater flow;

• characterize the groundwater/surface water interaction at the Station, including a determination of the surface water flow regime;

• evaluate groundwater quality at the Station including the vertical and horizontal extent, quantity, concentrations, and potential sources of tritium and other radionuclides in the groundwater, if any;

• define the probable sources of any radionuclides released at the Station;

• evaluate potential human, ecological, or environmental receptors of any radionuclides that might have been released to the groundwater; and

• evaluate whether interim response activities are warranted.

045136 (16) LaSalle Generating Station 1 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 2.0 STATION DESCRIPTION The following section presents a general summary of the Station location and definition, overview of Station operations, surrounding land use, and an overview of both regional and Station-specific topography, surface water features, geology, hydrogeology, and groundwater flow conditions. This section also presents an overview of groundwater use in the area.

2.1 STATION LOCATION The Station consists of approximately 3,055 acres, of which approximately 7 acres are used for generating electricity. The remaining 2,981 acres of property encompass an approximate 2,058-acre cooling lake (LaSalle Lake) and the land associated with the blowdown and make-up water pipelines.

This report uses the following definitions:

• PA - the PA is the area contained within the perimeter fencing where the generating facilities, warehouses, training center, switchyard and other critical Station features are located; and

• Site - the Site includes the PA and the area immediately surrounding the PA within the perimeter vehicle barrier. The Site is approximately 7 acres.

2.2 OVERVIEW OF COOLING WATER OPERATIONS The Station operates two boiling water reactors, design Type 5 (BWR-5) units manufactured by General Electric. The BWR-5 units are each capable of generating a net electrical output of 1,140 megawatts. Construction of the Station structures commenced in 1974 and both reactor units began commercial operation in 1984. The Station operates the two BWR-5 reactor units to generate power under Nuclear Regulatory Commission (NRC) Operating License Nos. NPF-11 and NPF-18, respectively. In addition to operating the two BWR-5 reactor units under the NRC licenses, the Station discharges wastewater and non-contact cooling water via eleven outfalls under its Illinois National Pollutant Discharge Elimination System (NPDES) Permit (IL 0048151).

The Station's BWR-5 Reactor Cooling Water System consists of two separate loops. Each loop is designed to avoid mixing the fluids of one loop with the fluids of another. The loops are called the primary loop and the secondary loop.

045136 (16) LaSalle Generating Station 2 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 The primary loop transfers the energy generated from fission in the fuel to the turbine to produce electricity. It is a closed-loop system. A byproduct of the nuclear fission is heat. After passing through the steam turbines and transferring the kinetic energy of the steam to the turbine to produce electricity, the steam then passes into the Main Condenser. In the Main Condenser, the remaining heat energy of the steam is transferred to the Circulating Water System changing the steam back into water. The condensate water is then circulated back to the reactor core to start the cycle over again through the Feed Water Pumps.

The main purpose of the secondary loop cooling water is to cool the other side of the Main Condenser, cooling the primary loop steam and transferring the heat to the environment. Cooling water is pumped from the unlined Intake Canal from LaSalle Lake to the Main Condenser. After passing through the Main Condenser, the heated cooling water is then discharged back to LaSalle Lake through the Circulating Water (CW) Discharge Pipe. The CW discharges into the unlined Discharge Canal. The Discharge Canal is located on the west side of the Site and flows in a clockwise direction around the Site back to LaSalle Lake. There are two "baffle" berms located within LaSalle Lake to increase the flow pathway through the lake and increase the heat removal process. In addition, make-up water is pumped into LaSalle Lake from the Illinois River while blowdown water is gravity-discharged from LaSalle Lake back to the Illinois River.

The blowdown and make-up water lines aid in reducing the dissolved mineral concentration in the lake water, which increase due to evaporation and aids in the dissipating of heat energy. Make-up water to the lake is pumped from the Illinois River at a rate of approximately 55,800 gallons per minute (gpm) while blowdown water from LaSalle Lake is discharged back to the Illinois River at a rate of approximately 32,980 gpm. The Illinois River is approximately 5 miles to the north of the Station. The combination of the make-up and blowdown lines from the Illinois River along with the movement of water from LaSalle Lake through the Main Condenser and back into LaSalle Lake constitute the secondary loop.

In addition to the primary and secondary loops, there are a number of support systems, such as the Residual Heat Removal (RHR) heat exchangers, the High Pressure Core Spray (HPCS), the Low Pressure Core Spray (LPCS), and the Suppression Pool which are independent of the primary and secondary loops. The RHR Heat Exchangers remove decay heat and excess heat from the Suppression Pool. LaSalle Lake water is pumped through the RHR Heat Exchangers and discharged back to LaSalle Lake also through the Core Standby Cooling System (CSCS). The HPCS, LPCS and the 045136 (16) LaSalle Generating Station 3 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Suppression Pool use purified water that is generated through the Station's Demineralizer Systems.

Liquid radiological waste is processed through the Station's Demineralizer Systems prior to being discharged to the blowdown line. Discharge was previously completed on a batch process at a maximum flow rate of 45 gpm, dependant upon dilution calculations, under the authority of the Station's NPDES Permit and NRC Operating Licenses. The Station policy since December 2000 is not to discharge radioactively contaminated fluid into the Radwaste discharge pipe that feeds into the blowdown line.

2.3 SURROUNDING LAND USE The land surrounding the Station to the north, east, west, and south is rural with farmland and wooded areas encompassing the greatest portion of the area immediately surrounding the Station. The blowdown and make-up pipelines are on an irregularly shaped narrow portion of land that extends northward from the Site to the Illinois River (Figure 1.2). To the east of this portion of land there are rural farms and residences. To the west of this portion of land there are also farms and residences along with the Marseilles State Fish and Wildlife Area and the Illinois National Guard Training Area.

The closest town, Seneca, has a population of approximately 2,000 people and is located approximately 4 miles to the north-northeast of the Site (Figure 1.2).

2.4 STATION SETTING The following sections present a summary of the topography, surface water features, geology, hydrogeology, and groundwater flow conditions in the region surrounding the Station. The information was primarily gathered from Sections 2.4 and 2.5 of the LaSalle Station Updated Final Safety Analysis Report (UFSAR) Revision 15 dated April 2004.

The main references UFSAR relies on are listed in Section 10.0 of this HIR. CRA checked and verified all UFSAR references that apply to this HIR.

2.4.1 TOPOGRAPHY AND SURFACE WATER FEATURES The Station's location is presented on the LaSalle Mosaic, Illinois 7.5-minute United States Geological Service (USGS) topographic quadrangle map (see Figure 1.1). The LaSalle Mosaic is comprised of the USGS topographic quadrangle maps Marseilles-1994, 045136 (16) LaSalle Generating Station 4 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Ransom-1983, Kinsman-1983, and Seneca-1970; Photorevised 1980. The topography of the region is predominately flat farmland with little relief.

The topography at the Station is generally flat with a gentle slope to the west-southwest, while within the PA the land is generally flat and covered by paved areas, roadways, and parking lots. Further northward from the Site, along the Illinois River, topographic relief is much more pronounced, with a mixture of gently rolling areas, gradual and deep ravines and flatland. Moving northward from the Station to the Illinois River, the elevation changes abruptly at about 4,000 feet from the River, where it descends rapidly to the River valley. The plains of the River valley, in the area of the blowdown/make-up pipelines lie at an elevation of approximately 500 feet above mean sea level (AMSL) (Figure 1.1).

The predominant surface water features in the area of the Station are LaSalle Lake, the Station's storm water retention ponds and the Illinois River. LaSalle Lake is an unlined man-made lake lying immediately east of the Station covering an area of approximately 2,058 acres. The Lake was constructed to function as the cooling lake for the Station.

The Lake varies in depth ranging from only a few feet in some areas to over 80 feet deep in other areas with an average depth of approximately 15 feet (UFSAR, Rev. 15, 2004).

The storm water retention ponds are located on the west side of the Station and receive storm water runoff from the PA. Storm water runoff from the PA is drained by a storm water system of surface ditches and underground piping, which discharge to an oil/water separator at the west side of the PA prior to entering the retention ponds. The cooling water discharge canal separates the two storm water retention ponds. The retention ponds discharge through a weir located at the northwest corner of the ponds into the cooling water discharge canal that is connected to LaSalle Lake located to the east of the Site.

The Illinois River is located approximately 5 miles north of the Station. The confluence of the Kankakee and Des Plaines Rivers, approximately 40 miles northwest of the Station near Joliet, Illinois forms the Illinois River. It flows west across northern Illinois at a rate of 12,600 cubic feet per second, eventually turning southwest and joining the Mississippi River near Grafton, Illinois. It is approximately 273 miles long and receives water from a 40,000 square mile drainage basin in central Illinois. The primary uses for the Illinois River are for transportation of bulk goods, recreation, sport fishing, and as a source of potable water (The Nature Conservancy, 2006).

045136 (16) LaSalle Generating Station 5 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 2.4.2 GEOLOGY LaSalle Station is located at the northern border of the Illinois Basin on the eastern flank of the LaSalle Anticlinal Belt, approximately 5 miles south of the Illinois River. Regional soil deposits in the Uplands portion of LaSalle Station consist predominantly of 120 to 200 feet or more of Pleistocene till resting on Pennsylvanian bedrock. Near the Illinois River valley, soil deposits consist of valley fill of the Ticona and Kempton Buried Bedrock Valleys (UFSAR, Rev. 15, 2004; Visocky et al., 1985).

The Station is between two minor folds at the northwest end of the LaSalle Anticlinal Belt, the Ransom Syncline and the Odell Anticline. Soil at the Site is generally Holocene to Wisconsinan in age, with minor amounts of Illinoian, Kansan, and pre-Kansan sediments reported in the area. Holocene sediments at the Site are primarily alluvium and colluvium along the Illinois River Valley ranging from less than 5 feet to approximately 25 feet in thickness. The Wisconsinan sediments are primarily glacial till (Wedron) and outwash deposits with minor amounts of loess, lacustrine, and ice-contact deposits, as well as some terrace gravels along the Illinois River (Visocky et al., 1985).

Figure 2.1 provides a geologic cross-section for the region.

Excavation activities completed during the construction of LaSalle Station confirmed that the Site is entirely within the Yorkville Till Member of the Wedron Formation (Wedron Clay Till). Borings indicated scattered occurrences of small sand and gravel pockets through the Wedron Clay Till (UFSAR, Rev. 15, 2004).

The bedrock units at the Site include nearly flat-lying Pennsylvanian cyclotherm sequences (limestones, shales, sandstones, coals) unconformably overlying Ordovician limestones, shales, dolomites, and sandstones. These units are part of very gently dipping (less than 1 degree), broad folds related to the LaSalle Anticlinal Belt. The Pennsylvanian Carbondale Formation beneath is exposed in narrow strips along the bluffs of the Illinois River (William and Frye, 1970). Refer to Figures 2.2 and 2.3 for the relationships between the units.

2.4.3 HYDROGEOLOGY At the Station's River Screen house, located approximately 4 miles north of the Site, the alluvial aquifer extends along the Illinois River and is bounded on the north by the River and on the south by the valley walls. The alluvial aquifer near the river screen house ranges in width from 3,500 to 4,800 feet. It is generally composed of two layers. The upper layer is alluvium and consists of silty clay or clayey silt overlain with organic 045136 (16) LaSalle Generating Station 6 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 material. The lower layer is glacial outwash and consists of silty sand, gravelly sand, and sand and gravel mixtures. The thickness of the alluvial aquifer ranges from 0.9 to 37 feet, becoming thicker to the east with an average thickness of 16.7 feet. This aquifer recharges by direct infiltration of precipitation and by inflow from the Illinois River. Groundwater discharge is directly to the river and to the underlying Pennsylvanian bedrock by slow seepage (Schicht et al., 1976, UFSAR, Rev. 15, 2004).

The glacial drift aquitard at the Station is composed of relatively impermeable Wedron Formation silty clay or clay tills with discontinuous pockets of well-graded sand and gravel. The Wedron Clay Till ranges in thickness from 0 foot at the bedrock outcrops along the Illinois River Valley to over 200 feet in the upland portion of the Station (Figure 2.2). The Wedron Clay Till underlies the Site and continues northward along the blowdown/make-up water pipelines until reaching the Illinois River Valley where it has been removed through erosion. The discontinuous pockets of well-graded sand and gravel within the Wedron Clay Till contain groundwater, and groundwater occurs predominantly under water table conditions, but occasionally as artesian conditions.

The permeable zones are recharged by slow infiltration of precipitation through the tills, while discharge is controlled under gravity flow into nearby river or stream valleys, underlying bedrock, to glaciofluvial deposits of the buried bedrock valley aquifers, or to pumping wells. The glacial drift aquitard at the Station is also recharged through seepage from LaSalle Lake, the Station intake and discharge canals, the storm water retention ponds as well as groundwater beneath the Station lying on top of the Wedron Formation (Arnold et al., 1999; UFSAR, Rev. 15, 2004).

The underlying Pennsylvanian aquitard consists of alternating beds of shale, siltstone, underclay, sandstone, limestone, coal, and many gradational units. Beneath the Station, the Pennsylvanian aquitard is approximately 180 feet in thickness and groundwater occurs under artesian conditions. Recharge to the Pennsylvanian aquitard is through seepage through the overlying shales and glacial drift (Figure 2.3) (Visocky et al., 1985).

Underlying the Pennsylvanian aquitard is the Cambrian-Ordovician Aquifer. The Cambrian-Ordovician Aquifer consists of various stratigraphic units of dolomite, limestone, and sandstone. Public groundwater use within 10 miles of the Station is obtained primarily from the lower Cambrian-Ordovician Aquifer (Visocky et al., 1985).

The buried bedrock valley aquifers consist of sand and gravel fill within valleys cut into the Pennsylvanian bedrock, mainly the east-west trending Ticona Bedrock Valley.

Recharge is primarily by seepage through the overlying clayey Wedron Clay Tills (Schicht et al., 1976).

045136 (16) LaSalle Generating Station 7 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 2.5 AREA GROUNDWATER USE Water supplies for the municipalities of Seneca (4 miles northeast of the Station),

Kinsman (6 miles southeast of the Station), Marseilles (6 miles northwest of the Station) and Illinois State Park (5 miles northwest of the Station) are taken directly from the Cambrian-Ordivician Aquifer. The municipality of Ransom (6 miles south of the Station) withdraws groundwater from both the Pennsylvanian aquitard and the Cambrian-Ordivician Aquifer. Grand Ridge (9 miles west of the Station) is the only municipality within 10 miles of the Station that withdraws groundwater from the glaciofluvial deposits of the buried Ticona Bedrock Valley. Residents of the surrounding rural areas and smaller communities not served by these public water supplies obtain groundwater from individual wells in the glacial drift, Pennsylvanian aquitard, glaciofluvial deposits of the buried Ticona Bedrock Valley, and the upper portions of the Cambrian-Ordivician Aquifer (UFSAR, Rev. 15, 2004).

The alluvial aquifer is generally less than 25 feet in thickness and is recharged through direct infiltration of precipitation and recharge from the Illinois River. The average pumping rate of the alluvial aquifer is 5,680 gpm (UFSAR, Rev. 15, 2004).

The glacial drift aquitard, which is in the Wedron Clay Till, is present throughout the regional area and ranges in thickness from 0 foot near the bedrock outcrops of the Illinois River valley to over 200 feet thick near the Station. The glacial drift aquitard consists predominantly of silty clay tills. LaSalle Station and the Site are underlain by the glacial drift aquitard. Typical permeabilities are 1.0 x 10-07 centimeters per second (cm/sec). Well yields from the glacial drift aquitard range between 2.5 gpm and 15 gpm (UFSAR, Rev. 15, 2004).

The glacial drift aquitard is underlain by Pennsylvanian bedrock composed of siltstone, shale, sandstone, clay, limestone, and coal. The Pennsylvanian strata may locally yield up to 20 gpm from the interbedded sandstones. Beneath the Pennsylvanian bedrock is the Cambrian-Ordovician aquifer, which is composed of a number of dolomite, limestone and sandstone strata. Water supply wells completed in this aquifer are at depths of over 400 feet below ground surface (bgs) and typically produce over 700 gpm.

The Station's deep Well No. 1 and Well No. 2 are completed in the Ironton-Galesville Sandstone at a depth of approximately 1,600 feet bgs (Visocky et al., 1985: UFSAR, Rev. 15, 2004).

CRA requested a search of the Illinois Department of Natural Resources State Water Survey (IDNR SWS, 2006) and the Illinois State Geological Survey (ISGS, 2006) database 045136 (16) LaSalle Generating Station 8 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 to identify wells within a 1-mile radius of the property line of the Station. As a result of the database search, 506 domestic, commercial and industrial wells were identified within a 2-mile distance from the Station property boundary. Figure 2.4 depicts the approximate location of the water wells identified in the database search. Information obtained from the IDNR SWS and ISGS database is in Appendix A along with a summary table of the information.

Residences located within an approximate 1-mile radius of the Station use groundwater for potable water supplies as well as irrigation and consumption by livestock. The wells are constructed in the overburden and bedrock and range in depth from approximately 10 feet bgs to over 1,600 feet bgs. The wells identified in the water well reports have not been field verified and it is expected, based on the dates of installation for some of the wells, that many of the wells listed have been abandoned.

045136 (16) LaSalle Generating Station 9 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 3.0 AREAS FOR FURTHER EVALUATION CRA considered all Station operations in assessing groundwater quality at the Station.

During this process, CRA identified areas at the Station that warranted further evaluation or "AFEs". This section discusses the process by which AFEs were selected.

CRA's identification of AFEs involved the following components:

• Station inspection on March 22 and 23, 2006;

• interviews with Station personnel;

• evaluation of Station systems;

• investigation of confirmed and unconfirmed releases of radionuclides; and

• review of previous Station investigations.

CRA analyzed the information collected from these components combined with information obtained from CRA's study of hydrogeologic conditions at the Station to identify those areas where groundwater potentially could be impacted from operations at the Station.

CRA then designed an investigation to determine whether any confirmed or potential releases or any other release of radionuclides adversely affected groundwater. This entailed evaluating whether existing Station groundwater monitoring systems were sufficient to assess the groundwater quality at the AFEs. If the systems were not sufficient to adequately investigate groundwater quality associated with any AFE, additional monitoring wells were installed by CRA.

The following sections describe the above considerations and the identification of AFEs.

The results of CRA's investigation are discussed in Section 5.0.

3.1 SYSTEMS EVALUATIONS Exelon launched an initiative to systematically assess the structures, systems and components that store, use, or convey potentially radioactively contaminated liquids.

Maps depicting each of these systems were developed and provided to CRA for review.

The locations of these systems are presented on Figures 3.1 and 3.2. The Station identified a total of 22 systems that contain or could contain potentially radioactively contaminated liquids. The following presents a list of these systems.

045136 (16) LaSalle Generating Station 10 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 System Identification Description CSCS Core Standby Cooling System CW Circulating Water CY Cycled Condensate Storage DL Laundry Drain Collector Sump DR Radwaste Building Floor Drains and Sump DT Units 1 and 2 Fire Sumps HD Feedwater Heater Drain Pumps HPCS High Pressure Core Spray LAS Surface Water Discharges LPCS Low Pressure Core Spray MISC Miscellaneous Releases OG Off-gas Building RE Reactor Building Equipment Drains RF Reactor Building Floor Drains RH Residual Heat Removal RI Reactor Core Isolation Cooling ST/TW/STORM WATER Sewage Treatment, Wastewater Treatment, Storm Water System TE Turbine Building Equipment Drains TF Turbine Building Floor Drain Sumps TW Wastewater Clarifiers WE/WF/WX/WY/WZ Equipment Drain Reprocessing Radwaste WL Blowdown and Make-up Pipelines After these systems were identified, Exelon developed a list of the various structures, components and areas of the systems (e.g., piping, tanks, process equipment) that handle or could potentially handle any radioactively contaminated liquids. The structures, components, and areas may include:

• aboveground storage tanks;

• condensate vents;

• areas where confirmed or potential historical releases, spills or accidental discharges may have occurred;

• pipes;

• pools;

• sumps;

• surface water bodies (i.e., basins, pits, ponds, or lagoons);

045136 (16) LaSalle Generating Station 11 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

• trenches;

• underground storage tanks; and

• vaults.

The Station then individually evaluated the various system components to determine the potential for any release of radioactively contaminated liquid to enter the environment. Each structure or identified component was evaluated against the following seven primary criteria:

• location of the component (i.e., basement or second floor of building);

• component construction material (i.e., stainless steel or steel tanks);

• construction methodologies (i.e., welded or mechanical pipe joints);

• concentration of radioactively contaminated liquid stored or conveyed;

• amount of radioactively contaminated liquid stored or conveyed;

• existing controls (i.e., containment and detection); and

• maintenance history.

System components, which were located inside a building or that otherwise had some form of secondary containment, such that a release of radioactively contaminated liquid would not be discharged directly to the environment, were eliminated from further evaluation. System components that are not located within buildings or did not have some other form of secondary containment were retained for further qualitative evaluation of the risk of a release of a radioactively contaminated liquid to the environment and the potential magnitude of any release.

Exelon's risk evaluation took into consideration factors such as:

• the potential concentration of radionuclides;

• the volume of liquid stored or managed;

• the probabilities of the systems actually containing radioactively contaminated liquid; and

• the potential for a release of radioactively contaminated liquid from the system component.

These factors were then used to rank the systems and system components according to the risk for a potential release of a radioactively contaminated liquid to the environment.

045136 (16) LaSalle Generating Station 12 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 The evaluation process resulted in the identification of structures, components, and areas to be considered for further evaluation.

3.2 HISTORICAL RELEASES CRA also reviewed information concerning confirmed or potential historical releases of radionuclides at the Station, including reports and documents previously prepared by Exelon and compiled for CRA's review. CRA evaluated this information in identifying the AFEs. Any historical releases identified during the course of this assessment that may have a current impact on Station conditions are further discussed in Section 3.4.

3.3 STATION INVESTIGATIONS CRA considered previous Station investigations in the process of selecting the AFEs for the Station. This section presents a summary of the pre-operational radiological environmental monitoring program (pre-operational REMP), past Station investigations, and the radiological environmental monitoring program.

3.3.1 PRE-OPERATIONAL RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM A pre-operational REMP was conducted to establish background radioactivity levels prior to operation of the Station. The environmental media sampled and analyzed during the pre-operational REMP were surface water, rainwater, drinking water, direct radiation, air particulate, sediment, and vegetation and animal products. The results of the monitoring were detailed in the report entitled "Environmental Radiological Monitoring for LaSalle County Nuclear Power Station, Commonwealth Edison Company, Annual Report, 1981", March 1982.

Atmospheric radiation monitoring consisted of gas and air particulate radioactivity measurements. Gross beta radioactivity in air particulate samples collected from 14 locations ranged from 0.01 picoCuries/cubic meter (pCi/m3) to 0.61 pCi/m3 with an average of 0.11 pCi/m3.

Results of gamma isotopic analyses of quarterly composite of air particulate filters from each sampling location indicated the absence of any gamma-emitters above the detection limit of the program of 0.01 pCi/m3.

045136 (16) LaSalle Generating Station 13 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Surface water samples were collected from eight locations along the Illinois River, at Marseilles, Ottawa, Seneca, as well as Kickapoo Creek, the Illinois Nitrogen Corporation raw water, the Recreational Area Cooling Lake and the LaSalle County Station (LSCS) intake and discharge pipes. Samples were analyzed for gross beta, gamma-emitters, tritium, and strontium-89/90. None of the composite samples indicated the presence of other than naturally occurring gamma-emitters at a lower limit of detection (LLD) of 10 picoCuries/liter (pCi/L). No samples contained strontium-89/90 at a LLD of 10 pCi/L. Tritium concentrations were variable ranging from <200 pCi/L to 350 pCi/L.

The gross beta analytical results in surface water samples were <10 pCi/L.

Drinking water samples were collected from an LSCS on-Site well and the following off-Site wells: Marseilles Well, Seneca Well, Ransom Well, Ottawa Well, and Illinois State Park Well. Gross beta analysis was performed on all samples. Gamma isotopic, radioactive strontium, and tritium analyses were conducted on the quarterly samples from the area wells and on a quarterly composite of monthly samples from the on-Site well. No unusual results were observed in analyses performed. However, several of the area wells had gross beta concentrations higher than that of nearby surface water.

Samples taken which contained higher beta concentrations are indicative of the presence of slightly elevated concentrations of naturally occurring radionuclides in groundwater.

Tritium concentrations in drinking water were variable, within the range of less than 200 pCi/L to 350 pCi/L. Gross beta analytical results in drinking water ranged from less than the LLD (1.6 pCi/L) to 22 pCi/L. In summary, the pre-operational REMP analytical results from samples collected from surface water and drinking water wells indicate that tritium was detected in both surface water and drinking water samples prior to Station operation.

Samples of precipitation were collected from four local farms on a monthly basis. All samples were analyzed for gross beta concentrations, and quarterly composites of monthly samples are analyzed for gamma-emitters, radioactive strontium, and tritium.

No unusual findings were made except for the presence of strontium-89/90 in the composites for the second quarter. Presence of this isotope in the precipitation is attributable to the fallout from the nuclear test conducted on October 16, 1980 by the Peoples Republic of China.

045136 (16) LaSalle Generating Station 14 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 3.3.2 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM The REMP at the Station was initiated in 1982. The REMP includes the collection of multi-media samples including air, surface water, groundwater, fish, sediment, and vegetation. The samples are analyzed for beta and gamma-emitting radionuclides, tritium, iodine-131, and/or strontium as established in the procedures developed for the REMP. The samples are collected at established locations, identified as stations, so that trends in the data can be monitored.

An annual report is prepared providing a description of the activities performed and the results of the analysis of the samples collected from the various media. The latest report generated was prepared by Station personnel and is entitled "LaSalle County Station, Units 1 and 2 - Annual Radiological Environmental Operating Report - 1 January Through 31 December 2005", May 2006. This report concluded that the operation of the Station had no adverse radiological impact on the environment. The annual report is submitted to the NRC.

As part of REMP, two surface water samples are collected weekly at two locations described as "Illinois River at Seneca, Upstream (control)" and "Illinois River, Downstream (indicator)" which have a location identification number in the REMP report as L-21 and L-40, respectively. Surface water data from 2005, indicate tritium sample concentration results range from less than the LLD (200 pCi/L) to 943 pCi/L.

The 943 pCi/L tritium concentration was detected in the surface water sample from location L-21 while it should also be noted that the sample from location L-40 had a tritium concentration of 821 pCi/L during the same sampling event.

Drinking water samples are collected at two locations described as "LSCS (LaSalle County Station) Onsite Well (indicator)" and "Marseilles Well (indicator)" which have a location identification number in the REMP report as L-27 and L-28, respectively.

Drinking water tritium sample concentration results were all less than the LLD (200 pCi/L).

3.3.3 HISTORIC INVESTIGATIONS This section summarizes investigations undertaken at the Station prior to this hydrogeologic investigation, related to actual or potential releases of radioactively contaminated liquids to the subsurface.

045136 (16) LaSalle Generating Station 15 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 3.3.3.1 POWER PLANT DOCUMENTS-UFSAR REPORT During the construction of the Station, a series of comprehensive investigations of regional and local geology, surface water, and groundwater conditions were conducted.

These studies were performed for a number of purposes including geotechnical evaluations of the underlying geologic deposits, present and future sources of groundwater, present and future groundwater use, and other engineering and environmental purposes. These studies are documented in the UFSAR, Rev. 15, 2004.

3.3.3.2 GROUNDWATER TRITIUM MONITORING PROGRAM Data exists for groundwater samples from four existing monitoring wells located in the area east and southeast of the Reactor Building. These monitoring wells were installed in response to the Units 1 and 2 HPCS CY line rupture in 1985. The Station collected monthly groundwater samples and analyzed them for tritium between January 1986 and September 1987. The highest detected tritium concentration within a groundwater well was approximately 11,000 pCi/L (HP-7). In addition to collecting water samples from four groundwater monitoring wells, the Station also collected groundwater samples from a drawdown borehole that was located approximately 40 feet west of well location HP-7. The drawdown borehole was installed to manage groundwater while repair activities to the HPCS lines were being completed. The highest detected tritium concentration from this drawdown borehole was 148,100 pCi/L. During the last sample collection event for the groundwater monitoring wells in 1987, one groundwater sample contained tritium at a concentration of 490 pCi/L (HP-7) while the other three wells were non-detect at the LLD. In addition to the installation of the four groundwater monitoring wells, the Station also installed several boreholes (HP-1, HP-3, HP-4, HP-6, HP-8, and HP-9) and collected soil samples for radionuclide analysis. A review of the historical data associated with the sampling of the HP-wells indicates a decreasing tritium trend from a high of 11,000 pCi/L (HP-7) to non-detect at the LLD (200 pCi/L).

For the drawdown borehole sample (identified as "caisson discharge composite"), the tritium decreased from an initial high concentration of 148,100 pCi/L to a low concentration of 5,740 pCi/L. No radionuclides were detected above their respective LLD in these samples. No stratigraphic or well construction information for the HP boreholes and wells was available for review. The wells HP-2, HP-5, HP-7, and HP-10 were sampled as part of the HIR investigation to evaluate the current condition of groundwater quality in this area of the historical Units 1 and 2 HPCS line ruptures. The results of the sampling are discussed further throughout Section 5.0.

045136 (16) LaSalle Generating Station 16 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 3.3.3.3 BLOWDOWN LINE INVESTIGATION In the spring of 2006, Station personnel collected discrete water samples from the vacuum breaker locations along the blowdown line where standing water was present.

A total of 16 out of 17 vacuum breakers (valve pit locations) had standing water present.

A water sample was collected and analyzed for tritium. All samples were non-detect with the exception of one sample collected from vacuum breaker valve pit #7, which had a tritium concentration of 274 +/- 129 pCi/L. The sample was re-analyzed using the distillation process resulting in a tritium concentration of less than the LLD of 200 pCi/L. This information was used in developing the AFEs associated with blowdown line.

3.4 IDENTIFIED AREAS FOR FURTHER EVALUATION CRA used the information presented in the above sections along with its understanding of the hydrogeology at the Station to identify AFEs, which were a primary consideration in the development of the scope of work in the Work Plan. The establishment of AFEs is a standard planning practice in hydrogeologic investigations to focus the investigation activities at areas where there is the greatest potential for impact to groundwater.

Specifically, AFEs were identified based on these six considerations:

• systems evaluations;

• risk evaluations;

• review of confirmed and/or potential releases;

• review of documents;

• review of the hydrogeologic conditions; and

• Station inspection completed on March 22 and 23, 2006.

Prior to CRA completing its analysis and determination of AFEs, Station personnel completed an exhaustive review of all historic and current management of systems that may contain potentially radioactively contaminated liquids.

CRA reviewed the systems identified by the Station, which have the potential for the release of radioactively contaminated liquids to the environment, and groundwater flow at the Station. This evaluation allowed CRA to become familiar with Station operations and potential systems that may impact groundwater. CRA then evaluated information 045136 (16) LaSalle Generating Station 17 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 concerning historic releases as provided by the Station. This information, along with a review of the results from historic investigations, was used to refine CRA's understanding of areas likely to have the highest possibility of impacting groundwater.

Where at risk systems or identified historical releases were located in close proximity or were located in areas which could not be evaluated separately, the systems and historical releases were combined into a single AFE. At times, during the Station investigation, separate AFEs were combined into one or were otherwise altered based on additional information and consideration.

Finally, CRA used its understanding of known hydrogeologic conditions (prior to this investigation) to identify AFEs. Groundwater flow was an important factor in deciding whether to combine systems or historical releases into a single AFE or create separate AFEs. For example, groundwater beneath several systems that contain radioactively contaminated liquids that flows toward a common discharge point were likely combined into a single AFE.

Based upon its review of information concerning confirmed or potential historical releases, historic investigations, and the systems at the Station that have the potential for release of radioactively contaminated liquids to the environment combined with its understanding of groundwater flow at the Station, CRA has identified the following as the AFEs (see Figures 3.1 and 3.2).

AFE-LaSalle-1: High Pressure Core Spray (HPCS)/Reactor Core Isolation (RI) Systems This area was identified as an AFE in order to investigate any residual contamination related to previous releases of tritiated water.

AFE-LaSalle-2: Reactor/Turbine/Radwaste Sumps This area was identified to evaluate the quality of groundwater in the area around the Reactor, Turbine and Radwaste Buildings. This AFE was established based on information regarding the storage, handling, and potential for releases from sumps within these buildings.

AFE-LaSalle-3: Cycled Condensate (CY) System In September 2001, the Unit 2 Cycled Condensate (CY) System storage tank overflowed.

No active remediation activities were completed relative to this AFE.

045136 (16) LaSalle Generating Station 18 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Blowdown Line AFEs (4 through 6)

AFEs LaSalle 4, 5, and 6, were established based on information regarding historical releases in this area.

AFE-LaSalle-4: Blowdown Line Vacuum Breaker 3A&B This area was identified as an AFE in order to investigate any residual contamination related to previous releases of tritiated water.

AFE-LaSalle-5: Blowdown Line Vacuum Breaker 15A&B This area was identified as an AFE in order to investigate any residual contamination related to previous releases of tritiated water.

AFE-LaSalle-6: Blowdown Line Vacuum Breaker 16B This area was identified as an AFE in order to investigate any residual contamination related to previous releases of tritiated water.

AFE-LaSalle-7: Radwaste Discharge Line This area was established as an AFE in order to evaluate and determine whether a tritium release to the environment had occurred during the operation of the Radwaste line. The Station has not discharged Radwaste through this line since December 2000.

Based on discussions with Station personnel and the level of tritium concentrations contained within water that was discharged through this line, further evaluation for the potential release of radioactively contaminated liquids was warranted.

045136 (16) LaSalle Generating Station 19 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 4.0 FIELD METHODS The field investigations completed for this HIR were completed in May and July 2006.

CRA supervised the installation of monitoring wells and staff gauges, collected samples from the newly-installed and existing monitoring wells, and collected samples from surface water locations. The field investigations were completed in accordance with the methodologies presented in the Work Plan (CRA, 2006).

4.1 STAFF GAUGES INSTALLATION Figure 4.1 presents the location of the four new staff gauges installed on July 6, 2006 as part of this investigation. CRA installed staff gauges at four locations (SG-LS-101 to 104) within the intake canal, the discharge canal, the north storm water retention pond, and the south storm water retention pond perimeter ditch in a manner appropriate with the depth and flow velocity of these surface water bodies to maintain the staff gauges in a stable position.

4.2 GROUNDWATER MONITORING WELL INSTALLATION Prior to completing any ground penetration activities, CRA completed subsurface utility clearance procedures to minimize the potential of injury to workers and/or damage to subsurface utility structures. The subsurface clearance procedures consisted of completing an electronic survey within a minimum of 10-foot radius of the proposed location utilizing electromagnetic and ground penetrating radar technology.

Additionally, an air knife was utilized to verify utilities were not present at the proposed location to a depth to 10 feet bgs.

Thirteen new monitoring wells were installed at the Station as part of the fleetwide hydrogeologic investigations. Monitoring well construction logs are provided in Appendix B. Figure 4.1 presents the location of 13 new monitoring wells (MW-LS-101S through MW-LS-113S). These locations were selected based on a review of all data provided, the hydrogeology at the Station, and current understanding of identified AFEs. Table 4.1 summarizes the well completion details. With the exception of MW-LS-110S, the remaining new wells were installed within and adjacent to the PA (four new wells within the PA and eight new wells outside the perimeter of the PA).

Well MW-LS-110S was installed adjacent to vacuum breaker 16B (AFE-LaSalle-6), which is located approximately 4 miles north of the Station in the Illinois River Valley. Due to 045136 (16) LaSalle Generating Station 20 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 its distance from the Site, this location was not used for determination of Site groundwater flow direction.

Specific installation protocols for the shallow monitoring wells are described below:

• the borehole was advanced to the target depth using 4.25-inch inside diameter hollow-stem augers (HSA);

• a nominal 2-inch diameter (No. 10 slot) PVC screen, 10 feet in length, attached to a sufficient length of 2-inch diameter schedule 40 PVC riser pipe to extend to the surface, was placed into the borehole through the augers;

• a filter sand pack consisting of silica sand was installed to a minimum height of 2 feet above the top of the screen as the augers were removed;

• a minimum 2-foot thick seal consisting of 3/8-inch diameter bentonite pellets or chips was placed on top of the sand pack and hydrated using potable water;

• the remaining borehole annulus was sealed to within 3 feet of the surface using pure bentonite chips;

• the remaining portion of the annulus was filled with concrete and a 6-inch diameter protective above-grade casing. The well head will be fitted with a water-tight, lockable cap; and

• cement-filled bollard posts were installed around selected monitoring well locations.

The shallow soil borings completed in unconsolidated materials that were to be used for monitoring well installation were installed using either Hydraulic Direct Push or 4.25-inch inside diameter (HSA) drilling techniques. The borehole depths ranged from 6.5 to 30 feet bgs. During the subsurface utility clearance activities described above, the borehole was periodically examined and the soil types documented. A description was added to each monitoring well construction log. The overburden soils were classified using the Unified Soil Classification System (USCS).

The following deviations from the Work Plan were noted during the installation of the monitoring wells due to depth or other area-specific constraints:

• At well location MW-LS-110S, bedrock refusal was encountered at 6.5 feet bgs.

Therefore, this monitoring well was installed using a 5-foot 2-inch #10 slot PVC screen, and no filter pack footing was installed, and this monitoring well was installed with the screen on top of the bedrock.

• At monitoring well locations MS-LS-104S/-105S/-106S/-108S/-109S/-110S/

-111S/-112S/-113S, bentonite seal was placed to a minimum 1-foot above the filter 045136 (16) LaSalle Generating Station 21 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 pack instead of the minimum of 2 feet above the filter pack. The above-specified wells were installed to such a shallow depth based on observed depths to groundwater, a 2-foot space above the filter pack could not be completed.

• For monitoring well locations MW-LS-101S/-102S/-103S/-107S/-108S/-109S/-111S flush mount well casings were installed instead of a standard stickup riser due to high traffic concerns in these areas.

4.3 GROUNDWATER MONITORING WELL DEVELOPMENT To establish good hydraulic communication with the aquifer and to reduce the volume of sediment in the monitoring well, CRA developed the monitoring wells. With the exception of monitoring wells MW-LS-101S/-102S/-103S/-106S/-108S/-110S/-111S/

-113S, all of the monitoring wells that were installed were developed in accordance with this procedure:

• Prior to the collection of hydraulic or groundwater quality data, the monitoring wells were developed using a 5-foot bailer. The bailer was allowed to fall freely through the monitoring well until it struck the surface of the water. The contact of the bailer produced a strong outward surge of water. As the bailer filled and was rapidly withdrawn, the drawdown created in the borehole caused the particulate matter outside the well intake to flow through the well intake and into the well.

• Subsequent bailing removed the sand and other particulate from the well.

• Development continued until the turbidity and silt content of the monitoring wells was significantly reduced or a minimum of five well volumes and not more than eight well volumes was removed.

Monitoring wells MW-LS-101S/-102S/-103S/-111S/ and -113S were dry upon installation, and therefore could not be developed. Monitoring wells MW-LS-106S/

-108S/ and -110S purged to dry after 7.5 volumes, 4.5 volumes, and 0.9 volumes were removed, respectively. The remaining wells were fully developed without incident.

CRA containerized the water purged during well development, and the containers were labeled as non-hazardous per directions from Station personnel. The containers were left, as directed by Station personnel, for prescreening and management at a later date by Station personnel.

Well development details are presented in Table 4.2.

045136 (16) LaSalle Generating Station 22 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 4.4 SURVEY The 13 new and four existing monitoring wells and the four staff gauge locations were surveyed to establish reference elevations relative to mean sea level. The top of each well casing was surveyed to the nearest 0.01 foot relative to the National Geodetic Vertical Datum (NGVD), and the survey point was marked on the well casing. The survey included the ground elevation at each well to the nearest 0.10 foot relative to the NGVD, and the well location to the nearest 1.0 foot.

4.5 GROUNDWATER AND SURFACE WATER ELEVATION MEASUREMENTS On May 22, 2006, CRA collected a round of water level measurements from the monitoring wells and staff gauges at the Station in accordance with the Work Plan. On July 6, 2006, CRA collected a second round of water level measurements from the monitoring wells and staff gauges at the Station. Based on the measured depth to water from the reference point and the surveyed elevation of the reference point, the groundwater or surface water elevation was calculated. A summary of groundwater elevations is provided in Table 4.3. A summary of the surface water elevations is provided in Table 4.4.

Prior to the water level measurements, the wells and staff gauges were identified and located. Once the wells were identified, CRA completed a thorough inspection of each well and noted any deficiencies. Water level measurements were collected using an electronic depth-to-water probe accurate to +/- 0.01 foot. The measurements were made from the designated location on the inner riser or steel casing of each monitoring well and reference point on each staff gauge. The water level measurements were obtained using the following procedures:

• the proper elevation of the meter was checked by inserting the tip into water and noting if the contact was registering correctly;

• the tip was dried, and then slowly lowered into the well or surface water body until contact with the water was indicated;

• the tip was slowly raised until the light and/or buzzer just began to activate. This indicated the static water level;

• the reading at the reference point was noted to the nearest hundredth of a foot;

• the reading was then re-checked; and 045136 (16) LaSalle Generating Station 23 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

• the water level was then recorded, and the water level meter decontaminated prior to use at the next location.

4.6 GROUNDWATER AND SURFACE WATER SAMPLE COLLECTION CRA conducted one round of groundwater sampling during the completion of the Work Plan for this hydrogeologic investigation. A total of 17 monitoring wells and five temporary sample locations were sampled between May 22 and 30, 2006.

Additional verification sampling at one well location was completed July 5, 2006. Of the 17 monitoring wells sampled, 13 were newly installed. The sampling was scheduled to allow for two weeks to elapse between well development and groundwater sample collection. The existing wells were selected for inclusion in this monitoring program based on their proximity to the AFEs.

At the monitoring well locations, with the exception of wells MW-LS-102S and MW-LS-113S which were dry, CRA conducted the sampling using dedicated tubing and peristaltic pumps to employ low flow purging techniques as described in Puls and Barcelona (1996).

The groundwater in the monitoring wells was sampled by the following low-flow procedures:

• the wells were located and the well identification numbers were verified;

• a water level measurement was taken;

• the well was sounded by carefully lowering the water level tape to the bottom of the well (so as to minimize penetration and disturbance of the well bottom sediment),

and comparing the sounded depth to the installed depth to assess the presence of any excess sediment or drill cuttings;

• the pump or tubing was lowered slowly into the well and fixed into place such that the intake was located at the mid-point of the well screen, or a minimum of two feet above the well bottom/sediment level;

• the purging was conducted using a pumping rate between 100 to 500 milliliters per minute (mL/min). Initial purging began using the lower end of this range. The groundwater level was monitored to ensure that a drawdown of less than 0.3 foot occurred. If this criterion was met, the pumping rate was increased dependent on the behavior of the well. During purging, the pumping rate and groundwater level were measured and recorded approximately every 10 minutes; 045136 (16) LaSalle Generating Station 24 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

• the field parameters [pH, temperature, conductivity, oxidation-reduction potential (ORP), dissolved oxygen (DO), and turbidity] were monitored during the purging to evaluate the stabilization of the purged groundwater. Stabilization was considered to be achieved when three consecutive readings for each parameter, taken at 5-minute intervals, were within the following limits:

pH +/- 0.1 pH units of the average value of the three readings, Temperature +/- 3 percent of the average value of the three readings, Conductivity +/- 0.005 milliSiemen per centimeter (mS/cm) of the average value of the three readings for conductivity <1 mS/cm and

+/- 0.01 mS/cm of the average value of the three readings for conductivity >1 mS/cm, ORP +/- 10 millivolts (mV) of the average value of the three readings, DO +/- 10 percent of the average value of the three readings, and Turbidity +/- 10 percent of the average value of the three readings, or a final value of less than 5 nephelometric turbidity units (NTUs);

• once purging was complete, the groundwater samples were collected directly from the pump/tubing directly into the sample containers; and

• in the event that the groundwater recharge to the monitoring well was insufficient to conduct the low-flow procedure, the well was pumped dry and allowed to sufficiently recharge prior to sampling.

All groundwater samples were labeled with a unique sample number, the date and time, the parameters to be analyzed, the job number, and the sampler's initials. The samples were then screened by the Station for shipment to Teledyne Brown Engineering Inc.,

(Teledyne Brown).

A sample key is presented in Table 4.5; field measurements for the hydrogeologic investigation are presented in Table 4.6.

CRA containerized the water purged from the monitoring wells during the sampling, as well as the water purged from all of the wells during the hydrogeologic investigation.

The water was placed into 55-gallon drums, which will be processed by the Station in accordance with its NPDES permit.

Surface water samples SW-LS-101 through SW-LS-103 were collected on May 23, 2006, SW-LS-106 was collected on May 24, 2006 and SW-LS-104 and SW-LS-105 were collected on May 25, 2006. The surface water sampling locations are presented on Figure 4.1.

045136 (16) LaSalle Generating Station 25 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 The surface water samples were collected by directly filling the sample container from the composite samplers at the determined locations until completely filled. A sample key is presented in Table 4.6.

4.7 DATA QUALITY OBJECTIVES CRA has validated the analytical data to establish the accuracy and completeness of the data reported. Teledyne Brown provided the analytical services. The Quality Assurance Program for the laboratory is described in Appendix C. Analytical data for groundwater and surface water samples collected in accordance with the Work Plan are presented in Appendix D. Data validation memo is presented in Appendix E. The data validation included the following information and evaluations:

• sample preservation;

• sample holding times;

• laboratory method blanks;

• laboratory control samples;

• laboratory duplicates;

• verification of laboratory qualifiers; and

• field quality control (field blanks and duplicates).

Following the completion of field activities, CRA compiled and reviewed the geologic, hydrogeologic, and analytical data.

The data were reviewed using the following techniques:

• data tables and databox figures;

• hydrogeologic cross-sections; and

• hydraulic analyses.

4.8 SAMPLE IDENTIFICATION Systematic sample identification codes were used to uniquely identify all samples. The identification code format used in the field was: WG - LS - MW-LS-101S - 052406 -

NK - 006. A summary of sample identification numbers is presented in Table 4.6.

045136 (16) LaSalle Generating Station 26 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 WG - Sample matrix -groundwater WS - Sample matrix - surface water RB - Sample matrix - rinse blank LS - Station code MW-LS-101S - Well Location 052406 - Date NK - Sampler initial 006 - Sample number 4.9 CHAIN-OF-CUSTODY RECORD The samples were delivered to Station personnel under chain-of-custody protocol.

Subsequently, the Station shipped the samples under chain-of-custody protocol to Teledyne Brown for analyses.

4.10 QUALITY CONTROL SAMPLES Quality control samples were collected to evaluate the sampling and analysis process.

Field Duplicates Field duplicates were collected to verify the accuracy of the analytical laboratory by providing two samples collected at the same location and then comparing the analytical results for consistency. Field duplicate samples were collected at a frequency of one duplicate for every ten samples collected. A total of three duplicate samples were collected. The locations of duplicate samples were selected in the field during the performance of sample collection activities. The duplicate samples were collected simultaneously with the actual sample and were analyzed for the same parameters as the actual samples.

Rinsate Blank Samples Rinsate blanks were collected to verify that decontamination procedures conducted in the field were adequate. Rinsate blanks were collected by routing Station-supplied demineralized water through decontaminated sampling equipment. Rinsate blanks were collected at a frequency of one rinsate blank for every day samples were collected 045136 (16) LaSalle Generating Station 27 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 using non-disposable or non-dedicated equipment. A total of two rinsate blanks were collected.

Split Samples Split samples were collected for the NRC for tritium simultaneously with the actual sample at every sample location. Split samples were delivered to the Station personnel and made available to the NRC.

4.11 ANALYSES Groundwater and surface water samples were analyzed for tritium and gamma-emitting radionuclides as listed in NUREG-1302 and strontium-89/90 as listed in 40 CFR 141.25.

4.12 ADDITIONAL FIELD ACTIVITIES 4.12.1 WELL INVENTORY CRA performed a comprehensive water well search of the IDNR SWS and ISGS databases. The results of the database search are in Appendix A.

In addition, CRA personnel conducted an evaluation of the viability of the four existing groundwater monitoring wells at the Station (HP-2, -5, -7, -10). Each well was sounded to determine a top of water elevation and a bottom of well depth and purged of 3- to 5-well volumes to evaluate groundwater recovery capabilities. Each well was determined to be functional and useable for this investigation. Stratigraphic and well construction information for these four wells were not available.

4.12.2 TEMPORARY SAMPLING POINT INSTALLATION CRA installed five temporary sampling points (TS-LS-101S through TS-LS-105S) using direct push techniques at points between the Station and the Illinois River (see Figure 4.1). These points were installed at locations along the Radwaste Discharge Line and the Blowdown Line to evaluate whether there has been any impact to the groundwater in these areas. TS-LS-101S and TS-LS-102S were located adjacent to vacuum breaker valves 15AB and 3AB, respectively (AFE-LaSalle-5 and AFE-LaSalle-4, respectively). The overburden soils were classified using the USCS. Immediately after 045136 (16) LaSalle Generating Station 28 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 installation and sampling, the sampling point was backfilled with borehole cuttings (with the exception of TS-LS-101S, where an existing open borehole was used).

4.12.3 TEMPORARY SAMPLING POINT SAMPLE COLLECTION At each temporary sampling point, a single grab sample of water was obtained from the water table immediately after borehole installation. The grab samples were obtained using a 3.0-foot bailer or peristaltic pump with tubing. The bailer or tubing was lowered to the water table, and without purging, the groundwater was immediately collected and placed into the sample containers. The only exception to this procedure was the groundwater sampling at TS-LS-105S. This location did not have sufficient groundwater present to fill all of the sample containers at once. Therefore, the groundwater sample was obtained over a three-day period using a peristaltic pump, allowing for recharge.

A sample key for the temporary sampling points is also presented in Table 4.6.

045136 (16) LaSalle Generating Station 29 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 5.0 RESULTS

SUMMARY

This section provides a summary of Station-specific geology and hydrogeology, along with a discussion of hydraulic gradients, groundwater elevations, and flow directions in the vicinity of the Station. This section also presents and evaluates the analytical results obtained from activities performed in accordance with the Work Plan.

5.1 STATION GEOLOGY The soil information collected from the installation of the permanent monitoring wells and temporary sampling point locations is consistent with the regional geology described in Section 2.4. The geology beneath the Site consists Wedron Clay Till resting on Pennsylvanian bedrock. Historic stratigraphic logs from the Station (UFSAR, Rev. 15, 2004) show that the Wedron Clay Till beneath the Station is more than 200 feet thick.

CRA prepared geologic cross-sections in both north-south and west-east profiles for the Station. Figure 5.1 displays the profile locations across the Site. The cross-sections are presented on Figures 5.2, 5.3, and 5.4. These cross-sections were chosen because of their close proximity to the AFEs and structures potentially influencing groundwater flow patterns.

The main building excavation for the Turbine/Reactor Building extends into the Wedron Clay Till to a maximum depth of 60 feet below the final surface grade while excavation activities for auxiliary buildings, ranged in depth from 5 to 30 feet below the final surface grade. In addition, the excavation for the intake structure and the CSCS piping extends into the Wedron Clay Till from 5 to 40 feet below grade surface. As a result of these construction activities, a trough or "bowl-like" depression at the top of the Wedron Clay Till has been created, containing the groundwater and influencing groundwater flow.

The 13 monitoring wells and five temporary sampling points installed were completed in the overburden fill and clay. The overburden consists of approximately 0.4 to 10 feet of compacted sand, gravel and clay fill material underlain by the Wedron Clay Till which is comprised of silty clay to clay with intermittent pockets of gravel and sand.

The stratigraphic and instrumentation logs showing well construction details for the newly installed monitoring wells are in Appendix B.

Profile A-A' is a north-south profile through the middle of the Site. It begins east of the old Exelon parking lot north of the northern fence line bordering the PA and terminates 045136 (16) LaSalle Generating Station 30 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 south of MW-LS-103S. This profile transects with AFE-LaSalle-2 (Reactor/Turbine/Rad Waste Sumps) in the northwest quarter of the PA. This profile shows the relationship between the geology, excavated areas, the Reactor Building foundation, and storm drains in the overburden materials. The Turbine/Reactor Building foundation was constructed in the Wedron Clay Till to an elevation of approximately 635 feet AMSL or approximately 60 feet bgs. The foundation of the Turbine/Reactor Building sits on a 1-foot thick lean concrete mud mat, which extends 10 feet out from the foundation in all directions to prevent sinking or shifting and a base foundation slab that consists of 7-foot thick reinforced concrete overlies the mud mat. The Turbine/Reactor Building foundation is not seated in bedrock. Engineered compacted fill was placed around the foundation of the Turbine/Reactor Building to the ground surface. The storm drainpipes along this sectional line are located in the fill above the clay till unit, to the north and south of the Turbine/Reactor Building.

Profile B-B' is a west-east profile through the middle of the Site. It begins outside the western perimeter fence line in the south storm water retention pond and terminates outside the eastern perimeter fence line at the switchyard. This profile cuts through AFE-LaSalle-3 [Cycled Condensate (CY) System] in the western portion of the PA and AFE-LaSalle-1 [High Pressure Core Spray (HPCS)/Reactor Core Isolation (RI) Systems]

in the middle of the PA. This profile shows the relationship between geology, excavated areas, the Turbine/Reactor Building foundation, and storm drains in the overburden materials. The Turbine/Reactor Building foundation in this area was constructed within the Wedron Clay Till to a depth of approximately 655 feet AMSL. The Turbine/Reactor Building foundation is not seated in bedrock. Engineered compacted fill was placed around the foundation of the Turbine/Reactor Building to the ground surface. The storm drainpipes along this sectional line are located in the compacted engineered fill above the clay till unit, to the south and west of the Turbine/Reactor Building. The historical pipe rupture area at AFE-LaSalle-1 is shown to be adjacent to the excavation of the Turbine/Reactor Building to the east, in the vicinity of HP-10. AFE-LaSalle-3 is located in the excavation area just southwest of the Turbine/Reactor Building.

Profile C-C' is a north-south profile through the western side of the Site, outside of the PA. It begins in the "Old Exelon Parking Lot" to the north of the PA, and terminates south of the "In-Processing Facility" to the south of the PA. This profile transects with the Circulating Water pipes that terminate at the discharge canal. This profile shows the relationship between geology, excavated areas, and the two Circulating Water pipes in the overburden material. The excavation for the Circulating Water pipes extends to approximately 680 feet AMSL, and was filled with engineered fill material. The pipes are approximately 12.5 feet in diameter. They discharge into the Discharge Canal.

045136 (16) LaSalle Generating Station 31 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 5.2 STATION HYDROGEOLOGY The hydrogeologic profiles are presented on Figures 5.2, 5.3, and 5.4. This profile uses the same A-A', B-B', and C-C' profile lines as shown on Figure 5.1 for the geologic cross-sections.

The monitoring wells at the Site were installed to monitor the shallow overburden, therefore, only the overburden hydrogeology is discussed in this section.

Field observations and stratigraphic information developed during the investigation indicates that the Station is underlain by granular fill, which is in turn underlain by the Wedron Clay Till. Groundwater is located in the fill material lying on top of the Wedron Clay Till. These observations are consistent with information provided by the Station in the UFSAR which indicates that the Station is underlain by Wedron Clay Till which is over 200 feet thick in the area of the Station. No borings for the investigation were advanced pass 50 feet bgs (MW-LS-103S and TS-LS-105S) and therefore the thickness of the Wedron Clay Till could not be confirmed. Soil samples from the borings indicated that once the Wedron Clay Till was encountered, it continued to the limit of the borehole (UFSAR, Rev. 15, 2004).

Along the blowdown line, field observations noted during the investigation indicated that the blowdown line, from the Station to the Illinois River Valley, is buried within the Wedron Clay Till. At the onset of the Illinois River Valley, the blowdown line is buried within the alluvium sediments and within bedrock. This was also consistent with the information outlined in the UFSAR (UFSAR, Rev. 15, 2004).

The groundwater contours (Figure 5.5) and top of clay contours (Figure 5.6) at the Site indicate that groundwater flow is divided from north to south in the area of monitoring well HP-2. East of the well, groundwater flows to the intake canal while west of the divide groundwater flows westward around the Reactor/Turbine Building into the storm water retention ponds and the discharge canal.

There are no groundwater pumping activities or slurry walls constructed at the Site that would affect overburden groundwater flow patterns to the nearby surface water bodies.

045136 (16) LaSalle Generating Station 32 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 5.2.1 GROUNDWATER FLOW DIRECTIONS The foundations or basements associated with the Turbine/Reactor Building extend to depths below the water table (approximately 60 feet bgs) into the Wedron Clay Till (refer to the geologic cross-sections on Figures 5.2, 5.3, and 5.4). These foundations/basements are barriers to groundwater flow in the overburden materials.

The wells installed by CRA at the Site were screened to monitor the interface between the fill and the top of the Wedron Clay Till (clay unit) unit and to delineate the groundwater flow along the top of the relatively impermeable clay unit. The Wedron Clay Till acts as barrier to vertical migration of groundwater and therefore limits groundwater movement to a predominantly horizontal component through the granular fill. Figure 5.5 shows the water table groundwater contours based on data collected May 22, 2006 for the Site. CRA utilized a commercially available contouring program (Surfer, Version 8.02, 2002) to provide an initial contouring of the measured groundwater elevations. The initial contours were then modified using professional judgment to prepare the final contour maps.

As shown on Figure 5.5, the general groundwater flow direction in the shallow overburden is to the southwest with an apparent low point southwest of the Turbine/Reactor Building near MW-LS-105S. The only subsurface feature that appears to be able to affect groundwater flow is the foundation of the Turbine/Reactor Building.

Schematic diagrams in the UFSAR show that the foundations of the Turbine/Reactor Building is approximately 60 feet bgs into the Wedron Clay Till (UFSAR, Ref. 15, 2004).

Therefore, shallow groundwater flow from the northeast portion of the Site is diverted north and south around the building foundation as it flows toward the west.

Figure 5.6 presents the top of clay unit contours based upon the well logs and building excavation details (UFSAR, 2004). As shown, the elevation of the top of clay ranges from 698.61 feet AMSL (MW-LS-104S) to 703.27 feet AMSL (MS-LS-107S). The elevation of the top of clay unit for the perimeter monitoring wells (outside of the PA) ranges from 704.54 feet AMSL (MW-LS-111S) to 710.85 feet AMSL (MW-LS-112S).

The elevation of the top of clay unit beneath the PA is approximately 1 to 12 feet lower than the elevation of the top of clay at the perimeter of the PA, indicating a depressed area in the natural clay exists beneath the PA near MW-LS-105S, MW-LS-104S, HP-7, and MW-LS-109S. These conditions create a "bowl" beneath the Site where groundwater accumulates until it fills the bowl. Based on the Reactor/Turbine Building excavation details the bowl is a result of the construction activities at the Site. In preparation for constructing the Reactor/Turbine Building complex and the underground circulating 045136 (16) LaSalle Generating Station 33 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 water pipelines, the overburden, which consisted of loess and Wedron Clay Till was excavated to a depth of approximately 60 feet below the final design grade elevation of approximately 710 feet AMSL. In order to safely complete the excavation activities, the side slopes were cut to a 1:1 slope that resulted in the excavation extending 20 to 30 feet beyond the foundations of the building. These areas of the excavation extending beyond the foundation walls were backfilled with granular fill. These construction excavation activities resulted in the present day bowl-like top of clay outline.

During wet conditions, groundwater flows into the bowl area from the northeast, filling the depression. As groundwater continues to flow into the depressed area of the Wedron Clay Till beneath the Site, eventually the depression fills up and overflows.

Once the depression is full, groundwater continues to flow to the west and southwest.

During dry conditions, with less groundwater flow into the depressed area, the groundwater that is able to flow into the depression would be trapped in the depression, unable to continue to flow west and southwest out of the depressed area, effectively isolating the groundwater beneath the Station from the local flow regime outside of the influence of the depressed area. Although groundwater may become trapped beneath the Station, any residual tritium impacts, as indicated by the presence of tritium in the groundwater sample from MW-LS-105S would be contained due to the Wedron Clay Till beneath the Station that extends to over 200 feet beneath the Station. Figure 5.7 shows the saturated thickness of the groundwater beneath the Station. As expected from the "bowl-like" conditions of the Wedron Clay Till, the saturated thickness is greatest in the vicinity of the Turbine/Reactor Building.

The groundwater flow is likely influenced by the excavation trenches used to install the intake and discharge pipelines. The removal of the clay and emplacement of engineered fill around the building foundations and pipelines would provide a preferential path for the movement of groundwater from the top of the clay till downward along the building foundations. These circumstances may be responsible for the low point in the groundwater elevation at MW-LS-105S.

5.2.2 MAN-MADE INFLUENCES ON GROUNDWATER FLOW The main building excavation for the Turbine/Reactor Building extends into the Wedron Clay Till to a maximum depth of 60 feet below the final surface grade. The sidewalls of the excavation were constructed at a 1:1 slope. Additional excavation activities within the main building excavation, for Auxiliary Buildings, ranged in depth from 5 to 30 feet below the final surface grade. Prior to erecting the Turbine/Reactor Building structure, the final Wedron Clay Till bearing surfaces were protected with a 045136 (16) LaSalle Generating Station 34 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 mud mat that consisted of a 1-foot thick layer of lean concrete. The mud mat extended 10 feet beyond the outsides of the building walls. A base foundation slab that consists of 7-foot thick reinforced concrete overlies the mud mat. The base foundation slab extends beneath the Turbine and the Reactor Building. In addition, the excavation for the intake structure and the CSCS piping extends into the Wedron Clay Till from 5 to 40 feet below grade surface.

The primary backfill installed around the main buildings (Turbine/Reactor/Auxiliary) and the CSCS piping consisted of C-6 structural fill, which is composed of sand and gravel materials (UFSAR, Rev. 15, 2004).

These construction activities and the use of a granular backfill resulted as a preferential pathway for the flow of groundwater beneath the Station since the granular fill would have higher hydraulic conductivity relative to the highly impermeable Wedron Clay Till.

In addition, LaSalle Lake is a man-made feature, which also influences groundwater flow at the Station. LaSalle Lake functions as a cooling lake and is immediately east of the Site, comprising over 2,058 acres of impounded water. To the west of the Station is the Discharge Canal and the storm water ponds. The Discharge Canal wraps around the northern portion of the Site and discharges back to LaSalle Lake. In addition to these surface water bodies, man-made Site features such as storm water underground piping and underground utilities will also provide preferential pathways for the migration of groundwater across the Site.

5.3 GROUNDWATER QUALITY CRA personnel collected groundwater samples from 15 wells and five temporary sampling locations. The samples were analyzed for tritium and additional radionuclides. Teledyne Brown provided the analytical services. The Quality Assurance Program for the laboratory is described in Appendix C. The analytical data reports are provided in Appendix D.

The analytical data presented herein has been subjected to CRA's data validation process. CRA has used the data with appropriate qualifiers where necessary.

The data reported in the figures and tables does not include the results of recounts that the laboratory completed, except if those results ultimately replaced an initial report.

The tables and figures, therefore, include only the first analysis reported by the 045136 (16) LaSalle Generating Station 35 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 laboratory. Where multiple samples were collected over time, then the most recent result has been used in the discussion, below.

5.3.1

SUMMARY

OF BETA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS A summary of the tritium results for the groundwater samples collected during this investigation is provided in Table 5.1 and shown on Figure 5.8.

All tritium concentrations were below the United States Environmental Protection Agency (USEPA) drinking water standard of 20,000 pCi/L. Tritium was not detected at concentrations greater than the LLD of 200 pCi/L in 19 of the 20 groundwater samples collected.

Further, tritium was only detected in one sample above the laboratory LLD of 200 pCi/L. The concentration of tritium in the May 26, 2006 groundwater sample from MW-LS-105S was 1,280 +/- 184 pCi/L. Monitoring well location MW-LS-105S was re-sampled on July 5, 2006 and the concentration of tritium in the groundwater sample was 766 +/- 153 pCi/L.

Strontium-89/90 was not detected at concentrations greater than the LLD of 2.0 pCi/L.

A summary of the strontium-89/90 results for the groundwater samples collected as part of the investigation that is the subject of this HIR is provided in Table 5.2 and shown on Figure 5.9.

5.3.2

SUMMARY

OF GAMMA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS Gamma-emitting target radionuclides were not detected at concentrations greater than their respective LLD. A summary of the gamma-emitting radionuclides results for the groundwater samples collected as part of the investigation that is the subject of this HIR is provided in Table 5.2 and shown on Figure 5.9.

Other non-targeted radionuclides were also included in the tables but excluded from discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

045136 (16) LaSalle Generating Station 36 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 5.3.3

SUMMARY

OF FIELD MEASUREMENTS A summary of the field measurement results for the groundwater samples collected as part of the investigation is provided in Table 4.6. These field measurements included pH, dissolved oxygen, conductivity, turbidity and temperature. The field parameters were typical of a shallow granular fill aquifer. pH values ranged from 6.46 standard units to 8.28 standard units. Temperature readings were slightly elevated within the PA area relative to readings from wells outside of the PA. However, the elevated temperature readings are likely due to transfer of residual heat from the Circulating Water piping buried beneath the Station PA. The conductivity was indicative of a shallow water table system subject to surface water recharge. Overall, the readings were within the expected ranges for naturally occurring groundwater.

5.4 SURFACE WATER QUALITY Six surface water samples were collected from the locations shown on Figure 4.1. The samples were analyzed for tritium, gamma-emitting radionuclides, and strontium-89/90. Teledyne Brown provided the analytical services. The Quality Assurance Programs for the laboratory is described in Appendix C. The analytical data reports are provided in Appendix D.

5.4.1

SUMMARY

OF BETA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS A summary of the tritium results for the surface water samples collected in this investigation is provided in Table 5.3 and shown on Figure 5.9. As shown in the table, the surface water samples from SW-LS-101 and SW-LS-106 contained tritium at concentrations of 232 +/- 116 pCi/L and 219 +/- 113 pCi/L, respectively.

Annual REMP reporting for surface water samples collected from the Illinois River indicates tritium concentrations in the Illinois River water samples ranging from non-detectable at the LLD of 200 pCi/L to as high as 1,682 pCi/L (2003 REMP Report).

In 2004 the average concentration of tritium in Illinois River water samples reported by the Station in their Annual REMP report was 521 pCi/L with a maximum of 1,058 pCi/L while in the 2005 report, the tritium concentrations ranged from non-detectable at the LLD of 200 pCi/L to 943 pCi/L.

045136 (16) LaSalle Generating Station 37 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Strontium-89/90 was not detected at concentrations greater than the LLD of 2.0 pCi/L.

A summary of the strontium-89/90 results for the surface water samples collected in this investigation is provided in Table 5.4 and shown on Figure 5.9.

5.4.2

SUMMARY

OF GAMMA-EMITTING RADIONUCLIDES ANALYTICAL RESULTS Gamma-emitting target radionuclides were not detected at concentrations greater than their respective LLD. A summary of the gamma-emitting radionuclide results for the surface water samples collected in this investigation is provided in Table 5.4 and shown on Figure 5.9.

Other non-targeted radionuclides were also included in the tables but excluded from discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

045136 (16) LaSalle Generating Station 38 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 6.0 RADIONUCLIDES OF CONCERN AND SOURCE AREAS This section discusses radionuclides evaluated in this investigation, potential sources of the radionuclides detected, and their distribution.

6.1 GAMMA-EMITTING RADIONUCLIDES Gamma-emitting target radionuclides were not detected at concentrations greater than their respective LLD. Other non-targeted radionuclides were also included in the tables but excluded from discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

6.2 BETA-EMITTING RADIONUCLIDES Strontium-89/90 was not detected in any of the 26 samples collected at concentrations that were greater than the LLD of 2.0 pCi/L. Tritium was detected in three of the 26 total sample locations. Concentrations of tritium ranged between less than the LLD of 200 pCi/L to 1,280 +/- 184 pCi/L.

Since only tritium was detected at concentrations greater than its LLD, the following sections focus on tritium; specifically, providing general characteristics of tritium, potential sources, distribution in groundwater, and a conceptual model for migration.

6.3 TRITIUM This section discusses the general characteristics of tritium, the distribution of tritium in groundwater and surface water, and the conceptual model of tritium release and migration.

6.3.1 GENERAL CHARACTERISTICS Tritium (chemical symbol H-3) is a radioactive isotope of hydrogen. The most common forms of tritium are tritium gas and tritium oxide, which is also called "tritiated water."

The chemical properties of tritium are essentially those of ordinary hydrogen. Tritiated 045136 (16) LaSalle Generating Station 39 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 water behaves the same as ordinary water in both the environment and the body.

Tritium can be taken into the body by drinking water, breathing air, eating food, or absorption through skin. Once tritium enters the body, it disperses quickly and is uniformly distributed throughout the body. Tritium is excreted primarily through urine within a month or so after ingestion. Organically bound tritium (tritium that is incorporated in organic compounds) can remain in the body for a longer period.

Tritium is produced naturally in the upper atmosphere when cosmic rays strike air molecules. Tritium is also produced during nuclear weapons explosions, as a by-product in reactors producing electricity, and in special production reactors, where the isotopes lithium-7 and/or boron-10 are bombarded to produce tritium.

Although tritium can be a gas, its most common form is in water because, like non-radioactive hydrogen, radioactive tritium reacts with oxygen to form water.

Tritium replaces one of the stable hydrogen atoms in the water molecule and is called tritiated water. Like normal water, tritiated water is colorless and odorless. Tritiated water behaves chemically and physically like non-tritiated water in the subsurface, and therefore tritiated water will travel at the same velocity as the average groundwater velocity.

Tritium has a half-life of approximately 12.3 years. It decays spontaneously to helium-3 (3He). This radioactive decay releases a beta particle (low-energy electron). The radioactivity of tritium is the source of the risk of exposure.

Tritium is one of the least dangerous radionuclides because it emits very weak radiation and leaves the body relatively quickly. Since tritium is almost always found as water, it goes directly into soft tissues and organs. The associated dose to these tissues is generally uniform and is dependent on the water content of the specific tissue.

6.3.2 DISTRIBUTION IN STATION GROUNDWATER This section provides an overview of the lateral and vertical distribution of tritium detected in groundwater at the Station. Tritium was detected in groundwater at concentrations exceeding the LLD of 200 pCi/L.

Tritium concentrations exceeding 200 pCi/L were detected in one groundwater sample collected from well MW-LS-105S at a concentration of 1,280 +/- 184 pCi/L. MW-LS-105S was re-sampled on July 5, 2006 and tritium was detected in the groundwater sample at 766 +/- 153 pCi/L. MW-LS-105S is adjacent to the Interim RadWaste Storage Facility, on 045136 (16) LaSalle Generating Station 40 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 the southwest side of the Turbine/Reactor Building in the PA. A review of the historical release information indicates that MW-LS-105S appears to be located upgradient of the historical release from the AFE-LaSalle Unit 2 Cycled Condensate Storage Tank. It is possible that this detection is the residual impact related to this previous release.

However, Site features that could have acted as interceptors and prevented the migration of tritium from the AFE-LaSalle-2 location northward to MW-LS-105S are a storm drain and the Off-Gas Underground pipelines (Figure 3.2).

6.3.3 DISTRIBUTION IN STATION SURFACE WATER Tritium concentrations exceeding 200 pCi/L were detected in two surface water samples, SW-LS-101 and SW-LS-106. Surface water samples from SW-LS-101 and SW-LS-106 had concentrations of tritium of 232 +/- 116 pCi/L and 219 +/- 113 pCi/L, respectively. SW-LS-101 was collected from the north storm water retention pond, which is connected to the Discharge Canal which feeds LaSalle Lake, and SW-LS-106 was collected from the Intake Canal emanating from the LaSalle Lake. Based upon the groundwater flow for the Station (see Figure 5.6), groundwater from the north side of the Reactor/Turbine Building appears to discharge to the north storm water retention pond while groundwater from the northeast corner of the Site discharges back to the intake canal. Although above the anticipated background concentration for tritium for the Site, the detections are not uncharacteristic of the data set over time. As part of the REMP, routine sampling of the Illinois River, which provides makeup water to LaSalle Lake, has consistently demonstrated tritium concentrations in both upstream and downstream surface water samples ranging from 1,680 pCi/L in 2003 to non-detectable at the LLD of 200 pCi/L during this hydrogeological investigation. As such, the detected concentrations of tritium in the two surface water samples collected as part of the hydrogeologic investigation are likely the result of elevated tritium concentrations in the Illinois River.

6.3.4 CONCEPTUAL MODEL OF TRITIUM RELEASE AND MIGRATION This section presents CRA's conceptual model of groundwater and tritium migration at the Station.

045136 (16) LaSalle Generating Station 41 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Hydrogeological Framework Groundwater flows through the overburden fill materials at the Site in response to the surface water bodies located to the east and west of the Site (Figure 5.1). Groundwater elevations indicate a groundwater divide extending from north to south near HP-2.

Groundwater to the east of HP-2 appears to flow eastward to the Intake Canal while groundwater to the west of HP-2 appears to flow west-southwest towards and around the Reactor/Turbine Building until it discharges to the storm water ponds and Discharge Canal to the west.

The underlying Wedron Clay Till, which is over 200 feet thick in the area of the Station, separates this overburden groundwater zone from regional overburden and bedrock aquifers. Construction activities have produced a depression in the top of the Wedron Clay Till also, which creates a minor groundwater depression surrounding the Reactor/Turbine Building. This groundwater depression also influences the horizontal movement of groundwater from east to west across the Site. Groundwater flowing through the overburden fill materials overlying the Wedron Clay Till, is also influenced by the presence of building foundations which extend into the top of the Wedron Clay Till. There are no slurry walls or groundwater pumping locations within the overburden fill material that would influence groundwater movement.

Vertical migration of radioactively contaminated liquids through the Wedron Clay Till is limited due to the very low permeability of the till (less than 1.0 x 10-07 cm/sec).

Sources and Migration of Tritium Tritium concentrations exceeding 200 pCi/L were detected in one groundwater sample at the Site from monitoring well MW-LS-105S.

The detection of tritium above 200 pCi/L in the groundwater sample from monitoring well MW-LS-105S appears to be localized to the area around the well. Tritium was not detected at the lower limit of detection of 200 pCi/L in the groundwater samples collected from monitoring wells in the vicinity and downgradient of this location.

The most likely source of the tritium in the groundwater at this well is from the historical release associated with the overflow of the Unit 2 Cycled Condensate Tank in 2001 (AFE-LaSalle-3) Discussion with Station personnel have been unable to define another possible source of the tritium detection.

045136 (16) LaSalle Generating Station 42 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Due to the low permeability of the Wedron Clay Till combined with the generally shallow east to west gradient of the water table and the apparent groundwater depression around MW-LS-105S, the tritiated water is not expected to migrate very far laterally from this monitoring well location.

There are two potential migration pathways for the tritiated groundwater found near MW-LS-105S:

• There is a potential for tritiated groundwater to discharge to the storm drain system (see Figure 3.2). The storm water drain invert nearest to MW-LS-105S is at approximately 705 feet AMSL. On May 22, 2006, the groundwater elevation at MW-LS-105S was 704.36 feet AMSL. This shows that the water table is below the invert of the nearest storm drain; however, as discussed in Section 5.2.2, there is a groundwater depression present at MW-LS-105S. It is possible that during high groundwater conditions, the water table may rise to the invert of the storm drain, allowing the tritiated groundwater to discharge into the storm drain. The groundwater that infiltrates the storm water system will flow to the oil/water separator to the west. This separator discharges water to the south storm water retention pond; and

• During periods of high groundwater elevations, it is possible that the groundwater near MW-LS-105S could flow northwest along the foundation of the Turbine/Reactor Building to the fill material for the discharge pipeline. The fill material surrounding the pipeline could create a preferential pathway for the migration of tritiated groundwater into the Discharge Canal.

There is no indication from the HIR investigation that tritium impacted groundwater is migrating off Site.

Surface Water As part of the Station's REMP, the Station collects water samples from the Illinois River quarterly, both upstream of the river intake and downstream of the blowdown line, which discharges to the Illinois River. The Station collects its upstream river sample from a boat pier/dock in the municipality of Seneca, Illinois which is located approximately 4 miles northeast of the Station and approximately 3.5 miles upstream of the Station's intake (make-up water line). The Station collects the downstream sample at a boat launch in Illinois State Park, which is located approximately 4.5 miles northwest of the Station and approximately 2 miles downstream of the blowdown line discharge.

Annual reporting of the average tritium concentrations for the last 3 years indicates 045136 (16) LaSalle Generating Station 43 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 tritium concentrations in the Illinois River, from water samples collected upstream and downstream of the Station, ranged from ND (2005 REMP Report) at the LLD of 200 pCi/L to as high as 1,682 pCi/L (2003 REMP Report).

In addition, a review of the groundwater contours presented on Figure 5.5 indicates that it would be highly unlikely that the tritium detected in the groundwater sample from MW-LS-105S could migrate eastward (against the groundwater gradient) and be the cause of the tritium detection in the intake canal. As previously stated in the section above, it is possible that tritium impacted groundwater from MW-LS-105S could migrate along the building foundation northward to the discharge canal piping and discharge into the discharge canal.

Based the historical tritium levels of the Illinois River and the volume of water that is pumped daily into LaSalle Lake from the Illinois River (80.4 million gallons per day), it is likely that the source of the detections of tritium in the two surface water samples are associated with the levels of tritium present in the Illinois River and not with impacted groundwater near MW-LS-105S.

045136 (16) LaSalle Generating Station 44 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 7.0 EXPOSURE PATHWAY ASSESSMENT This section addresses the groundwater impacts from tritium and other radionuclides at the Station and potential risks to human health and the environment.

Based upon historical knowledge and data related to the Station operations, and based upon radionuclide analyses of groundwater samples, the primary constituent of concern (COC) is tritium. The discussions that follow are restricted to the exposure pathways related to tritium.

Teledyne Brown reports all samples to their statistically derived minimum detectable concentration (MDC) of approximately 150 to 170 pCi/L, which is associated with 95 percent confidence interval on their hard copy reports. However, the laboratory uses a 99 percent confidence range (+/- 3 sigma) for determining whether to report the sample activity concentration as detected or not. This 3-sigma confidence range typically equates to 150 (+/- 135.75) pCi/L.

Exelon has specified a LLD of 200 pCi/L for the Fleetwide Assessment. Exelon has also required the laboratory to report related peaks identified at the 95 percent confidence level (2-sigma).

This HIR, therefore, screens and assesses data using Exelon's LLD of 200 pCi/L. As is outlined below, this concentration is also a reasonable approximation of the background concentration of tritium in groundwater at the Station.

7.1 HEALTH EFFECTS OF TRITIUM Tritium is a radionuclide that decays by emitting a low-energy beta particle that cannot penetrate deeply into tissue or travel far in air. A person's exposure to tritium is primarily through the ingestion of water (drinking water) or through ingestion of water bearing food products. Inhalation of tritium requires the water to be in a vapor form (i.e., through evaporation or vaporization due to heating). Inhalation is a minor exposure route when compared to direct ingestion or drinking of tritiated water.

Absorption of tritium through skin is possible, but tritium exposure is more limited here versus direct ingestion or drinking of tritiated water.

045136 (16) LaSalle Generating Station 45 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

7.2 BACKGROUND

CONCENTRATIONS OF TRITIUM The purpose of the following paragraphs is to establish a background concentration through review of various media.

7.2.1 GROUNDWATER Tritium is created in the environment from naturally occurring processes both cosmic and subterranean, as well as from anthropogenic (i.e., man-made) sources. In the upper atmosphere, "cosmogenic" tritium is produced from the bombardment of stable nuclides and combines with oxygen to form tritiated water, which will then enter the hydrologic cycle. Below ground, "lithogenic" tritium is produced by the bombardment of natural lithium isotopes 6Li (92.5 percent abundance) and 7Li (7.5 percent abundance) present in crystalline rocks by neutrons produced by the radioactive decay of uranium and thorium. Lithogenic production of tritium is usually negligible compared to other sources due to the limited abundance of lithium in rock. The lithogenic tritium is introduced directly to groundwater.

A major anthropogenic source of tritium comes from the former atmospheric testing of thermonuclear weapons. Levels of tritium in precipitation increased during the 1950s and early 1960s, coinciding with the release of significant amounts of tritium to the atmosphere during nuclear weapons testing prior to the signing of the Limited Test Ban Treaty in 1963, which prohibited atmospheric nuclear tests.

7.2.2 PRECIPITATION DATA Precipitation samples are routinely collected at stations around the world for the analysis of tritium and other radionuclides. Two publicly available databases that provided tritium concentrations in precipitation are Global Network of Isotopes in Precipitation (GNIP) and USEPA's RadNet database. GNIP provides tritium precipitation concentration data for samples collected world wide from 1960 to 2006.

RadNet provides tritium precipitation concentration data for samples collected at Stations through the U.S. from 1960 up to and including 2006.

Based on GNIP data for sample stations located in the U.S. Midwest including Chicago, St. Louis and Madison, Wisconsin, as well as Ottawa Ontario, and data from the University of Chicago, tritium concentrations peaked around 1963. This peak, which approached 10,000 pCi/L for some stations, coincided with the atmospheric testing of 045136 (16) LaSalle Generating Station 46 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 thermonuclear weapons. Tritium concentrations showed a sharp decline up until 1975 followed by a gradual decline since that time. Tritium concentrations in Midwest precipitation have typically been below 100 pCi/L since around 1980.

The RadNet database for several stations in the U.S. Midwest (Chicago, Columbus, Indianapolis, Lansing, Madison, Minneapolis, Painesville, Toledo, and Welsch, MN) did not show the same trend, which can attributed to pre-1995 data handling procedures.

The pre-1995 data were rounded to the nearest 100 pCi/L, which damped out variances in the data. The post-1995 RadNet data, where rounding was not applied, exhibit much more scatter, and similar to the GNIP data, the vast majority of the data were less than 100 pCi/L.

CRA constructed a non-parametric upper tolerance limit with a confidence of 95 percent and coverage of 95 percent based on RadNet data for USEPA Region 5 from 2004 to 2005. The resulting upper tolerance limit is 133 pCi/L, which indicates that CRA is 95 percent confident that 95 percent of the ambient precipitation concentration results are below 133 pCi/L. The statistical confidence, however, must be compared with the limitations of the underlying RadNet data, which does not include the minimum detectable concentration for a majority of the measurements. Some of the RadNet values below 200 pCi/L may be approximated. Nevertheless, these results show a background contribution for precipitation of up to 133 pCi/L.

7.2.3 SURFACE WATER DATA Tritium concentrations are routinely measured in large surface water bodies, including Lake Michigan and the Mississippi River. Surface water data from the RadNet database for Illinois sampling stations include East Moline (Mississippi River), Moline (Mississippi River), Marseilles (Illinois River), Morris (Illinois River), Oregon (Rock River), and Zion (Lake Michigan). As is the case for the RadNet precipitation data, the pre-September 1995 Illinois surface water data was rounded to the nearest 100 pCi/L, creating a dampening of variances in the data. The post-1995 Illinois surface water data, similar to the post-1995 Midwest precipitation data, were less than 100 pCi/L with the exception of the Moline (Mississippi River) station. Tritium surface water concentrations at this location varied between 100 and 800 pCi/L, which may reflect local natural or anthropogenic inputs.

For the Lake Michigan station, the surface water concentrations were less than 100 pCi/L, with the exception of a couple of occasions occurring around 1996 to 1997.

Tritium concentrations in Lake Michigan would be expected to be lower than 045136 (16) LaSalle Generating Station 47 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 precipitation concentrations given the 99-year surface water residence time within Lake Michigan, which corresponds to 8 half-lives of tritium and the dilution provided the large volume of the Lake (1,180 cubic miles) as well as seasonal mixing effects (WDNR, 1999).

Recent surface water measurements for tritium sampling locations upstream and downstream of the LaSalle Generating Station show that concentrations in the Illinois River consistently range between below 200 pCi/L to as high as 1,682 pCi/L (REMP, 2003, 2004, & 2005).

Surface water samples were taken from eight locations, along the Illinois River at Marseilles, Ottawa, Seneca, as well as Kickapoo Creek, the Illinois Nitrogen Corporation Raw, the Recreational Area Cooling Lake and the LSCS intake and discharge pipes.

Samples were analyzed for gross beta content, gamma-emitters, tritium, and strontium-89/90. None of the composite samples indicated the presence of other than naturally occurring gamma-emitters at a sensitivity of 10 pCi/L. No samples contained strontium-89/90 at a detection level of 10 pCi/L. Tritium concentrations were ranged from less than the LLD of 200 pCi/L to 350 pCi/L. The Gross beta analytical results in surface water samples were less than the LLD of 10 pCi/L.

The USEPA RadNet surface water data typically has a reported 'Combined Standard Uncertainty' of 35 to 50 pCi/L. According to USEPA, this corresponds to a

+/- 70 to 100 pCi/L 95 percent confidence bound on each given measurement. Therefore, the typical background data provided may be subject to measurement uncertainty of approximately +/- 70 to 100 pCi/L.

7.2.4 DRINKING WATER DATA Tritium concentrations in drinking water from the RadNet database for three Illinois sampling stations (Chicago, Morris, and East Chicago) exhibit similar trends as the precipitation and surface water data. As with the precipitation and surface water data, the pre-1995 data has dampened out variances due to rounding the data to the nearest 100 pCi/L. The post-1995 results show tritium concentrations in samples of drinking water were less than 100 pCi/L and less than the tritium concentrations found in precipitation and surface water.

Drinking water samples were taken from an LSCS on-Site well and the following off-Site wells: Marseilles Well, Seneca Well, Ransom Well, Ottawa Well, and Illinois State Park Well. Gross beta analysis was performed on all samples. Gamma isotopic, radioactive 045136 (16) LaSalle Generating Station 48 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 strontium, and tritium analyses were conducted on the quarterly samples from the area wells and on a quarterly composite of monthly samples from the on-Site well. No unusual results were observed in analyses preformed. However, several of the area wells had gross beta concentrations higher than that of nearby surface water. Sample results, which show samples contained higher beta concentrations, are indicative of the presence of slightly elevated concentrations of naturally occurring radionuclides in subsurface water. Tritium concentrations were variable, within the range of less than 200 pCi/L to 350 pCi/L. Gross beta analytical results in drinking water ranged from less than the LLD of 1.6 pCi/L to 22 pCi/L.

7.2.5 EXPECTED TRITIUM BACKGROUND FOR THE STATION As reported in the GNIP and RadNet databases, tritium concentrations in U.S. Midwest precipitation has typically been less than 100 pCi/L since 1980. Tritium concentrations reported in the RadNet database for Illinois surface water and groundwater, at least since 1995, has typically been less than 100 pCi/L. Based on the USEPA Region 5's 2004 to 2005 RadNet precipitation data, 95 percent of the ambient concentrations of tritiated water in Illinois are expected to be less than 133 pCi/L, based on a 95 percent confidence limit. Tritium concentrations in surface water and drinking water are expected to be comparable or less based on historical data and trends.

Concentrations in groundwater similar to surface and drinking water are expected to be less than precipitation values. The lower groundwater concentrations are related to the age of the groundwater as compared to the half-life of tritium. Deep aquifers in proximity to crystalline basement rock, however, can potentially show elevated concentrations of tritium due to lithogenic sources.

According to the 1981 pre-operational REMP, groundwater well sample results from off-Site wells indicated tritium levels ranged from a maximum of 360 +/- 100 pCi/L to a less than the LLD of 200 pCi/L. On-Site well sample results indicated tritium levels ranged from a maximum of 300 pCi/L to less than the LLD of 200 pCi/L.

As noted in Section 7.0, the analytical laboratory is reporting tritium results to a LLD of 200 pCi/L. This concentration also represents a reasonable representation of background groundwater quality, given the data for precipitation, surface water, and drinking water.

Based on the evaluation presented above, the background concentration for tritium at the Station is reasonably represented by the LLD of 200 pCi/L.

045136 (16) LaSalle Generating Station 49 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 7.3 IDENTIFICATION OF POTENTIAL EXPOSURE PATHWAYS AND POTENTIAL RECEPTORS Three potential exposure pathways were considered during the evaluation of tritium in groundwater.

• potential groundwater migration to the Station's potable water supply well;

• potential groundwater migration off the Station property to private and public groundwater users; and

• potential groundwater migration off the Station property to a surface water body.

The following section provides an overview of each of these three potential exposure pathways for tritium in groundwater.

7.3.1 POTENTIAL GROUNDWATER MIGRATION TO DRINKING WATER USERS AT THE STATION Based on the groundwater elevation data, there appears to be a groundwater divide at monitoring well location HP-2. Groundwater east of the divide flows northeast back to the intake canal while groundwater to the west of the divide flows to the west towards the Reactor/Turbine Building, around the building and eventually discharges into the discharge canal and storm water ponds on the west side of the Station. Although tritiated groundwater could migrate horizontally to the east and west from the divide, there is no exposure route for the ingestion of tritiated groundwater on the Station. The Station receives its potable water from a cased 1,600-foot bedrock well on the Site, which is installed in the Ironton-Galesville Sandstone. The vertical movement of tritiated water from the shallow overburden into deeper formations is restricted by the Wedron Clay Till, which is highly impermeable. Since vertical migration of tritiated water through the impermeable Wedron Clay Till to the Ironton-Galesville Aquifer is restricted but theoretically not eliminated, this is a potentially complete exposure pathway but there is no current risk for groundwater ingestion at the Station.

045136 (16) LaSalle Generating Station 50 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 7.3.2 POTENTIAL GROUNDWATER MIGRATION TO DRINKING WATER USERS OFF THE STATION PROPERTY Off-Site migration of tritium impacted groundwater is highly unlikely since groundwater elevation data indicates that the Site groundwater discharges to the Intake and Discharge Canals and the storm water ponds at the Site. Since there is no off-Site migration, tritium concentrations detected are less than the USEPA drinking water standard of 20,000 pCi/L, and there are no potable water supply wells in the overburden groundwater zone, there is no potentially complete exposure pathway, therefore, there is no current risk for groundwater ingestion off the Station property.

Groundwater samples were also collected adjacent to vacuum breakers associated with historical releases along the blowdown line. The results of the tritium analysis were non detect at the LLD of 200 pCi/L. Potential private wells could theoretically extract groundwater that is sourced from this area, but the groundwater immediately adjacent to the blowdown line is not impacted by tritium. As such, this is a potentially complete exposure pathway, but there is no current risk for groundwater ingestion off the Station property.

7.3.3 POTENTIAL GROUNDWATER MIGRATION TO SURFACE WATER USERS Under this potential exposure route groundwater must migrate from the Station property to nearby LaSalle Lake at concentrations greater than the 20,000 pCi/L drinking water and surface water standards. Potential exposures could occur if the groundwater discharge to the surface water body was sufficient to increase tritium levels in LaSalle Lake to levels above 20,000 pCi/L. Current surface water data for LaSalle Lake and one of the Station's storm water retention ponds indicates tritium concentrations slightly above 200 pCi/L. The highest tritium concentration in the groundwater at the Station is 1,280 +/- 184 pCi/L (MW-LS-105S), which is significantly less than the Illinois surface water standard of 20,000 pCi/L. There is no indication from the HIR investigation that tritium impacted groundwater from the area of MW-LS-105S is migrating off the Station into the adjacent LaSalle Lake. This is a potentially complete exposure pathway, but there is no current risk for ingestion off the Station property.

045136 (16) LaSalle Generating Station 51 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 7.4

SUMMARY

OF TRITIUM EXPOSURE PATHWAYS In summary, there are three potential exposure pathways for tritium originating at the Station:

• potential groundwater migration to the Station potable water supply well;

• potential groundwater migration off the Station property to private and public groundwater users; and

• potential groundwater migration off the Station property to a surface water user.

Based upon the groundwater and surface water data provided and referenced in this report, none of the potential receptors are at risk of exposure to concentrations of tritium in excess of the USEPA drinking water standard (20,000 pCi/L).

7.5 OTHER RADIONUCLIDES Target radionuclides were not detected in the groundwater and surface water samples collected at concentrations greater than their respective LLD. Other non-targeted radionuclides were also included in the tables but excluded from discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

045136 (16) LaSalle Generating Station 52 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

8.0 CONCLUSION

S Based on this hydrogeologic investigation, CRA concludes:

Groundwater Flow

• The groundwater table beneath LaSalle Station is in the overburden, which consists of granular fill and silty clay. Depth to water ranges from 2 to 7.5 feet bgs.

• There is an isolated groundwater trough beneath the PA to the southwest of the Turbine/Reactor Building due to a depression in the Wedron Clay Till which acts like a bowl; trapping groundwater beneath the PA.

• There appears to be a groundwater divide extending from north to south in the area of the existing monitoring well HP-2. Groundwater to the east of HP-2 flows towards and discharges into the intake canal while groundwater to the west of the divide flows to the west around the Reactor/Turbine Building into the storm water retention ponds and discharge canal located west of the PA.

• Groundwater flow within the PA is affected by the foundations of the Reactor/Turbine Building structure, which is constructed in the Wedron Clay Till.

This building is a barrier to horizontal groundwater flow to the west.

• The deeper bedrock and overburden water supply aquifers are separated from the Station groundwater by the Wedron Clay Till. There are two potable bedrock wells installed in the Ironton-Galesville Sandstone at a depth of approximately 1,600 feet bgs. These wells are cased from the surface into bedrock.

• The Station building structures were not constructed through the Wedron Clay Till and as such the Wedron Clay Till has not been penetrated by the Station construction activities. Also the Wedron Clay Till has a very low permeability.

Therefore, it continues to restrict downward vertical movement of groundwater.

• Groundwater appears to discharge to the north and south storm water retention ponds.

Groundwater Quality

• Tritium concentrations in groundwater were not detected at concentrations greater than the USEPA drinking water standard of 20,000 pCi/L.

• Tritium was not detected at concentrations greater than the LLD (200 pCi/L) in 19 of the 20 groundwater samples collected as part of this investigation.

045136 (16) LaSalle Generating Station 53 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

• Tritium was detected in a groundwater sample from monitoring well MW-LS-105S at a concentration of 1,280 +/- 184 pCi/L. A second groundwater sample collected from MW-LS-105S had tritium detected at a concentration of 766 +/- 153 pCi/L.

• The source of tritium in the groundwater sample from monitoring well MW-LS-105S is most likely attributable to historical spills. Samples obtained from adjacent monitoring wells and surface water locations revealed no detectable tritium levels.

The tritium detected in the groundwater sample from MW-LS-105S is localized to the area of that well.

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in 20 of the 20 groundwater samples collected as part of this investigation.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in 20 of the 20 samples collected as part of this investigation.

Surface Water Quality

• Tritium concentrations in surface water were not detected at concentrations greater than the USEPA drinking water standard of 20,000 pCi/L.

• Tritium was not detected at concentrations greater than the LLD (200 pCi/L) in four of the six surface water samples collected as part of this investigation.

• Tritium was detected at a concentration of 219 +/- 113 pCi/L in sample SW-LS-106 collected from the intake canal (Circulating Water Inlet).

• Tritium was detected at a concentration of 232 +/- 116 pCi/L in sample SW-LS-101 collected from the north Storm Water Retention Pond.

• The likely source of the tritium detections are from the Illinois River since the Station pumps over 80 million gallons per day of Illinois River Water into LaSalle Lake.

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in six of the six surface water samples collected as part of this investigation.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in six of the six surface water samples collected as part of this investigation.

AFE-LaSalle High Pressure Core Spray (HPCS)/Reactor Core Isolation (RI) Systems

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in any of the 045136 (16) LaSalle Generating Station 54 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 groundwater samples collected from the monitoring wells in the vicinity of AFE-LaSalle-1.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in any of the groundwater samples collected from the monitoring wells in the vicinity of AFE-LaSalle-1.

• Tritium was not detected at concentrations greater than the LLD of 200 pCi/L in any of the groundwater samples collected from the monitoring wells in the vicinity of AFE-LaSalle-1.

• There is no current impact from this AFE to groundwater at the Station.

• The groundwater samples collected from monitoring wells HP-2, HP-5, HP-7, and HP-10 installed to evaluate AFE-LaSalle-1 did not contain tritium, targeted gamma-emitting radionuclides, or strontium-89/90 at concentrations greater than their respective LLDs. This AFE is not a source of radionuclides to groundwater.

AFE-LaSalle Reactor/Turbine/Radwaste Sumps and AFE-LaSalle Cycled Condensate (CY) System

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in any of the groundwater samples collected from the monitoring wells in the vicinity of AFE-LaSalle-2 and -3.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in any of the groundwater samples collected from the monitoring wells in the vicinity of AFEs-LaSalle-2 and -3.

• The groundwater samples collected from monitoring wells HP-2, HP-5, HP-7, HP-10, MW-LS-104S, and MW-LS-107S installed to evaluate AFEs-LaSalle-2 and -3 did not contain tritium, targeted gamma-emitting radionuclides, or stronium-89/90 at concentrations greater than their respective LLDs.

• Tritium was detected at a concentration of 1,280 +/- 184 pCi/L at monitoring well MW-LS-105S. Re-sampling of this well on July 5, 2006 verified the presence of tritium. Tritium was detected in the second groundwater sample at a concentration of 766 +/- 153 pCi/L.

• The source of tritium in monitoring well MW-LS-105S is most likely from a historical release associated with the CY Storage Tank overflow in 2001. Samples obtained from adjacent monitoring wells and surface water locations revealed no detectable tritium levels. The tritium detected in MW-LS-105S is localized to the area of that well.

045136 (16) LaSalle Generating Station 55 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 AFE-LaSalle Blowdown Line Valve/Vacuum Breaker 3A&B:

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-4.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-4.

• Tritium was not detected at concentrations greater than the LLD of 200 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-4.

• The groundwater samples collected from temporary sampling point TS-LS-102S installed adjacent to VB-3A&B installed to evaluate AFE-LaSalle-4 did not contain tritium, targeted gamma-emitting radionuclides, or strontium-89/90 at concentrations greater than their respective LLDs. This AFE is not a source of radionuclides to groundwater.

• There is no current impact from this AFE to groundwater at the Station.

AFE-LaSalle Blowdown Line Valve/Vacuum Breaker 15A&B:

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-5.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-5.

• Tritium was not detected at concentrations greater than the LLD of 200 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-5.

• The groundwater samples collected from temporary sampling point TS-LS-101S installed adjacent to VB-15A&B to evaluate AFE-LaSalle-5 did not contain tritium, targeted gamma-emitting radionuclides, or strontium-89/90 at concentrations greater than their respective LLDs. This AFE is not a source of radionuclides to groundwater.

• There is no current impact from this AFE to groundwater at the Station.

045136 (16) LaSalle Generating Station 56 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 AFE-LaSalle Blowdown Line Valve/Vacuum Breaker 16B:

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-6.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-6.

• Tritium was not detected at concentrations greater than the LLD of 200 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-6.

• The groundwater samples collected from temporary sampling point TS-LS-110 installed adjacent to VB-16B installed to evaluate AFE-LaSalle-6 did not contain tritium, targeted gamma-emitting radionuclides, or strontium-89/90 at concentrations greater than their respective LLDs. This AFE is not a source of radionuclides to groundwater.

• There is no current impact from this AFE to groundwater at the Station.

AFE-LaSalle-7 -Radwaste Discharge Line:

• Gamma-emitting radionuclides associated with licensed plant operations were not detected at concentrations greater than their respective LLDs in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-7.

• Strontium-89/90 was not detected at a concentration greater than the LLD of 2.0 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-7.

• Tritium was not detected at concentrations greater than the LLD of 200 pCi/L in any of the groundwater samples collected from the temporary sampling locations in the vicinity of AFE-LaSalle-7.

• The groundwater samples collected from temporary sampling point TS-LS-103S, TS-LS-104S and TS-LS-105S installed adjacent to the Radwaste Discharge Line to evaluate AFE-LaSalle-7 did not contain tritium, targeted gamma-emitting radionuclides, or strontium-89/90 at concentrations greater than their respective LLDs. The Station discontinued the discharge of Radwaste through this line in December 2000. This AFE is not a source of radionuclides to groundwater.

• There is no current impact from this AFE to groundwater at the Station.

045136 (16) LaSalle Generating Station 57 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Potential Receptors

• Based on the results of this investigation 1 , there is no current risk from exposure to radionuclides associated with licensed plant operations through any of the identified potential exposure pathways.

General Conclusions

• Based on the results of this investigation, tritium is not migrating off the Station property at detectable concentrations.

• Based on the results of this investigation, there are no known active releases into the groundwater at the Station.

1 Using the LLD specified in this HIR.

045136 (16) LaSalle Generating Station 58 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 9.0 RECOMMENDATIONS The following presents CRA's recommendations for proposed activities to be completed at the Station.

9.1 DATA GAPS Based on the results of this hydrogeologic investigation, there are no data gaps remaining to support CRAs conclusions regarding the characterization of the groundwater regime and potential impacts from radionuclides at the Station.

9.2 GROUNDWATER MONITORING Based upon the information collected to date, CRA recommends that Exelon conduct periodic monitoring of selected sample locations.

045136 (16) LaSalle Generating Station 59 CONESTOGA-ROVERS & ASSOCIATES

Revision 1

10.0 REFERENCES

CITED Commission's Office of Nuclear Reactor Regulation, "Final Environmental Statement (NUREG-0486)", November 1978.

CRA Site Visit, May 2006.

Eisenbud, Merril and Gesell, Thomas, 1997. Environmental Radioactivity From Natural, Industrial, and Military Sources, Fourth Edition.

Exelon, 2005. Quad Cities Nuclear Power Station, 2004 Annual Radiological Environmental Operating Report, Exelon, Cordova, Illinois, May 2005.

Exelon, May 2006. "LaSalle County Station, Units 1 and 2 - Annual Radiological Environmental Operating Report - 1 January Through 31 December 2005".

Hazelton Environmental Science, March 1982. "Environmental Radiological Monitoring for LaSalle County Nuclear Power Station, Commonwealth Edison Company, Annual Report 1981".

International Joint Commission, August 1997. 1995-97 Priorities and Progress Under the Great Lakes Water Quality Agreement, http://www.ijc.org/php/publications/html/pr9597.html, International Joint Commission.

MDEQ, 2002. Use of Tritium in Assessing Aquifer Vulnerability, http://www.deq.state.mi.us/documents/deq-dwrpd-gws-wpu-Tritium.pdf, access on June 15, 2006.

Puls, R.W., and M.J. Barcelona, April 1996. Low-Flow (Minimal Drawdown)

Ground-Water Sampling Procedures, EPA Ground Water Issue, EPA/540/S-92/005, R. S. Kerr Environmental Research Center, United States Environmental Protection Agency, Ada, Oklahoma.

Schicht, Richard J., J. Rodger Adams, and John B. Stall, 1976. Water Resources Availability, Quality, and Cost in Northeastern Illinois, Illinois State Water Survey Report of Investigation 83.

The Nature Conservancy, 2006: Web Page Citation, (www.nature.org/initiatives/freshwater/work/illinoisriver.html)

UFSAR, 2004: Exelon. Updated Final Safety Analysis Report (UFSAR) Revision 15, April 2002. Chapters 2.4 and 2.5.

USGS, 1999. Radium in Ground Water from Public Water Supplies in Northern Illinois, USGS Fact Sheet 137-99.

Visocky et al., Adrian P., 1997. Water-Level Trends and Pumpage in the Deep Bedrock Aquifers in the Chicago Region, 1991-1995, Illinois State Water Survey Circular 182.

045136 (16) LaSalle Generating Station 60 CONESTOGA-ROVERS & ASSOCIATES

Revision 1 Visocky et al., Adrian, P., Marvin G. Sherrill, and Keros Cartwright, 1985. Geology, Hydrogeology, and Water Quality of the Cambrian and Ordovician Systems in Northern Illinois, Illinois State Geological Survey, Illinois State Water Survey, Cooperative Groundwater Report 10.

Willman, H.B. and J.C. Frye, 1970. Pleistocene Stratigraphy of Illinois, Bulletin 94, Illinois State Geological Survey.

Willman, H.B., E. Atherton, T.C. Buschbach, C. Collinson, J.C. Frye, M.E. Hopkins, J.A. Lineback, J.A. Simon, 1975. Handbook of Illinois Stratigraphy, ISGS Bulletin 95.

WNDR, 1999. Great Lakes Facts, Wisconsin Lakes Pub-FM-800-99Rev.

045136 (16) LaSalle Generating Station 61 CONESTOGA-ROVERS & ASSOCIATES

TABLE 4.5 SAMPLE KEY FLEETWIDE ASSESSMENT Page 1 of 1 LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location Sample Identification QC Sample Date Time Matrix Analyses Monitoring Wells MW-LS-101S WG-LS-MW-LS-101S-052406-NK-006 05/24/06 10:50 Groundwater Tritium / Target Radionuclides MW-LS-102S No sample collected. Location was dry. 05/25/06 MW-LS-103S WG-LS-MW-LS-103S-052306-NK-001 05/23/06 11:00 Groundwater Tritium / Target Radionuclides MW-LS-104S WG-LS-MW-LS-104S-052606-NK-020 05/26/06 11:00 Groundwater Tritium / Target Radionuclides MW-LS-105S WG-LS-MW-LS-105S-052606-NK-019 05/26/06 11:10 Groundwater Tritium / Target Radionuclides MW-LS-105S WG-LS-MW-105S-070506-JW-026 07/05/06 10:20 Groundwater Tritium MW-LS-106S WG-LS-MW-LS-106S-052506-NK-017 05/25/06 10:05 Groundwater Tritium / Target Radionuclides MW-LS-107S WG-LS-MW-LS-107S-052606-NK-018 05/26/06 9:20 Groundwater Tritium / Target Radionuclides MW-LS-108S WG-LS-MW-LS-108S-052506-NK-016 05/25/06 8:40 Groundwater Tritium / Target Radionuclides MW-LS-109S WG-LS-MW-LS-109S-052606-NK-021 05/26/06 12:55 Groundwater Tritium / Target Radionuclides Rinsate RB-LS-052506-NK-010 Rinsate 05/25/06 - water Tritium / Target Radionuclides MW-LS-110S WG-LS-MW-LS-110S-052506-NK-011 05/25/06 10:40 Groundwater Tritium / Target Radionuclides MW-LS-111S WG-LS-MW-LS-111S-053006-BW-022 05/30/06 11:06 Groundwater Tritium / Target Radionuclides MW-LS-111S WG-LS-MW-LS-111S-053006-BW-023 Duplicate (022) 05/30/06 11:26 Groundwater Tritium / Target Radionuclides MW-LS-112S WG-LS-MW-LS-112S-053006-BW-024 05/30/06 13:11 Groundwater Tritium / Target Radionuclides MW-LS-112S WG-LS-MW-LS-112S-053006-BW-025 Duplicate (024) 05/30/06 13:21 Groundwater Tritium / Target Radionuclides MW-LS-113S No sample collected. Location was dry. 5/30/2006 HP-2 WG-LS-HP-2-052406-NK-012 05/24/06 11:00 Groundwater Tritium / Target Radionuclides HP-5 WG-LS-HP-5-052406-NK-013 05/24/06 12:00 Groundwater Tritium / Target Radionuclides HP-7 WG-LS-HP-7-052406-NK-015 05/24/06 13:40 Groundwater Tritium / Target Radionuclides HP-10 WG-LS-HP-10-052406-NK-014 05/24/06 12:45 Groundwater Tritium / Target Radionuclides Temporary Sampling Points TS-LS-101S WG-LS-TS-LS-101S-050906-BW-001 05/09/06 10:55 Groundwater Tritium / Target Radionuclides TS-LS-102S WG-LS-TS-LS-102S-050506-BW-002 05/05/06 10:45 Groundwater Tritium / Target Radionuclides TS-LS-103S WG-LS-TS-LS-103S-050506-BW-003 05/05/06 13:55 Groundwater Tritium / Target Radionuclides TS-LS-104S WG-LS-TS-LS-104S-050506-BW-004 05/05/06 16:00 Groundwater Tritium / Target Radionuclides TS-LS-105S WG-LS-TS-LS-105S-050906-BW-005 05/09/06 9:15 Groundwater Tritium / Target Radionuclides Surface Water SW-LS-101 WS-LS-SW-LS-101-052306-NK-002 05/23/06 12:30 Surface Water Tritium / Target Radionuclides SW-LS-102 WS-LS-SW-LS-102-052306-NK-003 05/23/06 13:00 Surface Water Tritium / Target Radionuclides SW-LS-103 WS-LS-SW-LS-103-052306-NK-004 05/23/06 13:30 Surface Water Tritium / Target Radionuclides Rinsate RB-LS-052306-NK-005 Rinsate 05/23/06 - Water Tritium / Target Radionuclides SW-LS-104 WS-LS-SW-LS-104-052506-NK-008 05/25/06 8:35 Surface Water Tritium / Target Radionuclides SW-LS-105 WS-LS-SW-LS-105-052506-NK-009 05/25/06 9:00 Surface Water Tritium / Target Radionuclides SW-LS-105 WS-LS-SW-LS-105-052506-NK-018 Duplicate (009) 05/25/06 9:00 Surface Water Tritium / Target Radionuclides SW-LS-106 WS-LS-SW-LS-106-052406-NK-007 05/24/06 13:30 Surface Water Tritium / Target Radionuclides Notes:

QC - Quality Control Target Radionuclides: Sr-89/90, Mn-54, Co-58, Fe-59, Co-60, Zn-65, Nb-95, Zr-95, Cs-134, Cs-137, Ba-140, and La-140 Duplicate (009) - Duplicate of sample number in parenthesis CRA 45136 (16) LaSalle Generating Station Revision 1

Page 1 of 1 TABLE 5.1 ANALYTICAL RESULTS

SUMMARY

- TRITIUM IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location Sample Identification QC Sample Sample Date Tritium (pCi/L) Result Error HP-2 WG-LS-HP-2-052406-NK-012 5/24/2006 ND (200) -

HP-5 WG-LS-HP-5-052406-NK-013 5/24/2006 ND (200) -

HP-7 WG-LS-HP-7-052406-NK-015 5/24/2006 ND (200) -

HP-10 WG-LS-HP-10-052406-NK-014 5/24/2006 ND (200) -

MW-LS-101S WG-LS-MW-LS-101S-052406-NK-006 5/24/2006 ND (200) -

MW-LS-102S Location dry; no sample collected. 5/25/2006 MW-LS-103S WG-LS-MW-LS-103S-052306-NK-001 5/23/2006 ND (200) -

MW-LS-104S WG-LS-MW-LS-104S-052606-NK-020 5/26/2006 ND (200) -

MW-LS-105S WG-LS-MW-LS-105S-052606-NK-019 5/26/2006 1280 +/-184 MW-LS-106S WG-LS-MW-LS-106S-052506-NK-017 5/25/2006 ND (200) -

MW-LS-107S WG-LS-MW-LS-107S-052606-NK-018 5/26/2006 ND (200) -

MW-LS-108S WG-LS-MW-LS-108S-052506-NK-016 5/25/2006 ND (200) -

MW-LS-109S WG-LS-MW-LS-109S-052606-NK-021 5/26/2006 ND (200) -

MW-LS-110S WG-LS-MW-LS-110S-052506-NK-011 5/25/2006 ND (200) -

MW-LS-111S WG-LS-MW-LS-111S-053006-BW-022 5/30/2006 ND (200) -

MW-LS-111S WG-LS-MW-LS-111S-053006-BW-023 Duplicate (022) 5/30/2006 ND (200) -

MW-LS-112S WG-LS-MW-LS-112S-053006-BW-024 5/30/2006 ND (200) -

MW-LS-112S WG-LS-MW-LS-112S-053006-BW-025 Duplicate (024) 5/30/2006 ND (200) -

MW-LS-113S Location dry; no sample collected. 5/30/2006 TS-LS-101S WG-LS-TS-LS-101S-050906-BW-001 5/9/2006 ND (200) -

TS-LS-102S WG-LS-TS-LS-102S-050506-BW-002 5/5/2006 ND (200) -

TS-LS-103S WG-LS-TS-LS-103S-050506-BW-003 5/5/2006 ND (200) -

TS-LS-104S WG-LS-TS-LS-104S-050506-BW-004 5/5/2006 ND (200) -

TS-LS-105S WG-LS-TS-LS-105S-050906-BW-005 5/9/2006 ND (200) -

MW-LS-105S WG-LS-MW-105S-070506-JW-026 7/5/2006 766 +/-153 Notes:

Samples analyzed by: Teledyne Brown Engineering, Inc.

QC - Quality Control ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH 7/12/2006 CRA 45136 (16) LaSalle Generating Station Revision 1

TABLE 5.2 Page 1 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: HP-2 HP-2 HP-5 HP-5 HP-7 HP-7 HP-10 HP-10 Sample Identification: WG-LS-HP-2-052406-NK-012 Result WG-LS-HP-5-052406-NK-013 Result WG-LS-HP-7-052406-NK-015 Result WG-LS-HP-10-052406-NK-014 Result Sample Date: 5/24/2006 Error 5/24/2006 Error 5/24/2006 Error 5/24/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) - ND (10) - ND (10) - ND (10) -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) - ND (30) - ND (30) - ND (30) -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L RNI - RNI - RNI - RNI -

Radium-226 pCi/L RNI - RNI - RNI - RNI -

Thorium-228 pCi/L RNI - RNI - RNI - RNI -

Thorium-232 pCi/L RNI - RNI - RNI - RNI -

Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.2 Page 2 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: MW-LS-101S MW-LS-101S MW-LS-103S MW-LS-103S MW-LS-104S MW-LS-104S Sample Identification: WG-LS-MW-LS-101S-052406-NK-006 Result WG-LS-MW-LS-103S-052306-NK-001 Result WG-LS-MW-LS-104S-052606-NK-020 Result Sample Date: 5/24/2006 Error 5/23/2006 Error 5/26/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) - ND (10) U* - ND (10) -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) - ND (30) - ND (30) U* -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L RNI - RNI - RNI -

Radium-226 pCi/L RNI - RNI - RNI -

Thorium-228 pCi/L RNI - RNI - RNI -

Thorium-232 pCi/L RNI - RNI - RNI -

Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.2 Page 3 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: MW-LS-105S MW-LS-105S MW-LS-106S MW-LS-106S MW-LS-107S MW-LS-107S Sample Identification: WG-LS-MW-LS-105S-052606-NK-019 Result WG-LS-MW-LS-106S-052506-NK-017 Result WG-LS-MW-LS-107S-052606-NK-018 Result Sample Date: 5/26/2006 Error 5/25/2006 Error 5/26/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) - ND (10) - ND (10) U* -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) - ND (30) - ND (30) -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L RNI - 71.49 +/-38.25 91.77 +/-37.12 Radium-226 pCi/L RNI - RNI - RNI -

Thorium-228 pCi/L RNI - RNI - RNI -

Thorium-232 pCi/L RNI - RNI - RNI -

Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.2 Page 4 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: MW-LS-108S MW-LS-108S MW-LS-109S MW-LS-109S MW-LS-110S MW-LS-110S Sample Identification: WG-LS-MW-LS-108S-052506-NK-016 Result WG-LS-MW-LS-109S-052606-NK-021 Result WG-LS-MW-LS-110S-052506-NK-011 Result Sample Date: 5/25/2006 Error 5/26/2006 Error 5/25/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) U* - ND (10) - ND (10) U* -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) - ND (30) - ND (30) -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L 68.74 +/-43.94 RNI - RNI -

Radium-226 pCi/L RNI - RNI - RNI -

Thorium-228 pCi/L RNI - RNI - RNI -

Thorium-232 pCi/L RNI - RNI - RNI -

Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.2 Page 5 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: MW-LS-111S MW-LS-111S MW-LS-111S MW-LS-111S MW-LS-112S MW-LS-112S Sample Identification: WG-LS-MW-LS-111S-053006-BW-022 Result WG-LS-MW-LS-111S-053006-BW-023 Result WG-LS-MW-LS-112S-053006-BW-024 Result Sample Date: 5/30/2006 Error 5/30/2006 Error 5/30/2006 Error Duplicate Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) - ND (10) - ND (10) -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) - ND (30) - ND (30) -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L RNI - RNI - 91.22 +/-46.34 Radium-226 pCi/L RNI - RNI - RNI -

Thorium-228 pCi/L RNI - RNI - RNI -

Thorium-232 pCi/L RNI - RNI - RNI -

Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.2 Page 6 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: MW-LS-112S MW-LS-112S TS-LS-101S TS-LS-101S TS-LS-102S TS-LS-102S Sample Identification: WG-LS-MW-LS-112S-053006-BW-025 Result WG-LS-TS-LS-101S-050906-BW-001 Result WG-LS-TS-LS-102S-050506-BW-002 Result Sample Date: 5/30/2006 Error 5/9/2006 Error 5/5/2006 Error Duplicate Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) - ND (10) U* - ND (10) U* -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) U* - ND (30) U* - ND (30) U* -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L RNI - RNI - 433.5 +/-43.89 Radium-226 pCi/L RNI - RNI - 93.4 +/-53.55 Thorium-228 pCi/L RNI - RNI - 14.91 +/-3.337 Thorium-232 pCi/L RNI - RNI - 15.47 +/-6.935 Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.2 Page 7 of 7 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN GROUNDWATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: TS-LS-103S TS-LS-103S TS-LS-104S TS-LS-104S TS-LS-105S TS-LS-105S Sample Identification: WG-LS-TS-LS-103S-050506-BW-003 Result WG-LS-TS-LS-104S-050506-BW-004 Result WG-LS-TS-LS-105S-050906-BW-005 Result Sample Date: 5/5/2006 Error 5/5/2006 Error 5/9/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) U* - ND (10) U* - ND (10) U* -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) U* - ND (30) U* - ND (30) U* -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

(1)

Non-Target Radionuclides Potassium-40 pCi/L 245.4 +/-41.16 74.47 +/-31.55 189.9 +/-37.42 Radium-226 pCi/L RNI - RNI - RNI -

Thorium-228 pCi/L 11.56 +/-3.275 RNI - 6.858 +/-3.337 Thorium-232 pCi/L RNI - RNI - RNI -

Notes:

Samples analyzed by: Teledyne Brown (1) - These non-targeted radionuclides are included in this table but excluded from the discussion in this report. These radionuclides were either a) naturally occurring and thus not produced by the Station, or b) could be definitively evaluated as being naturally occurring due to the lack of presence of other radionuclides which would otherwise indicate the potential of production from the Station.

RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.4 Page 1 of 3 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN SURFACE WATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: SW-LS-101 SW-LS-101 SW-LS-102 SW-LS-102 SW-LS-103 SW-LS-103 Sample Identification: WS-LS-SW-LS-101-052306-NK-002 Result WS-LS-SW-LS-102-052306-NK-003 Result WS-LS-SW-LS-103-052306-NK-004 Result Sample Date: 5/23/2006 Error 5/23/2006 Error 5/23/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) U* - ND (10) U* - ND (10) U* -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) U* - ND (30) - ND (30) -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

Notes:

Samples analyzed by: Teledyne Brown RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.4 Page 2 of 3 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN SURFACE WATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: SW-LS-104 SW-LS-104 SW-LS-105 SW-LS-105 SW-LS-105 SW-LS-105 Sample Identification: WS-LS-SW-LS-104-052506-NK-008 Result WS-LS-SW-LS-105-052506-NK-009 Result WS-LS-SW-LS-105-052506-NK-018 Result Sample Date: 5/25/2006 Error 5/25/2006 Error 5/25/2006 Error Duplicate Units Target Radionuclides Barium-140 pCi/L ND (60) - ND (60) - ND (60) -

Cesium-134 pCi/L ND (10) - ND (10) U* - ND (10) U* -

Cesium-137 pCi/L ND (18) - ND (18) - ND (18) -

Cobalt-58 pCi/L ND (15) - ND (15) - ND (15) -

Cobalt-60 pCi/L ND (15) - ND (15) - ND (15) -

Iron-59 pCi/L ND (30) - ND (30) - ND (30) -

Lanthanum-140 pCi/L ND (15) - ND (15) - ND (15) -

Manganese-54 pCi/L ND (15) - ND (15) - ND (15) -

Niobium-95 pCi/L ND (10) - ND (10) - ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) - ND (2) - ND (2) -

Zinc-65 pCi/L ND (30) - ND (30) - ND (30) -

Zirconium-95 pCi/L ND (10) - ND (10) - ND (10) -

Notes:

Samples analyzed by: Teledyne Brown RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

TABLE 5.4 Page 3 of 3 ANALYTICAL RESULTS

SUMMARY

- RADIONUCLIDES IN SURFACE WATER FLEETWIDE ASSESSMENT LASALLE GENERATING STATION MARSEILLES, ILLINOIS Sample Location: SW-LS-106 SW-LS-106 Sample Identification: WS-LS-SW-LS-106-052406-NK-007 Result Sample Date: 5/24/2006 Error Units Target Radionuclides Barium-140 pCi/L ND (60) -

Cesium-134 pCi/L ND (10) -

Cesium-137 pCi/L ND (18) -

Cobalt-58 pCi/L ND (15) -

Cobalt-60 pCi/L ND (15) -

Iron-59 pCi/L ND (30) -

Lanthanum-140 pCi/L ND (15) -

Manganese-54 pCi/L ND (15) -

Niobium-95 pCi/L ND (10) -

Strontium-89/90 (Total) pCi/L ND (2) -

Zinc-65 pCi/L ND (30) -

Zirconium-95 pCi/L ND (10) -

Notes:

Samples analyzed by: Teledyne Brown RNI- Radionuclide Not Identified during analysis.

NA - Data not available or not analyzed.

ND ( ) - Non-detect; value in parentheses is the LLD.

LLD - Lower limit of detection.

- - Non-detect value, +/- value not reported.

q006AI-XT2-WG WS-0506 Groundwater Surface Water-37-TH CRA 45136 (16) LaSalle Generating Station 7/12/2006

Revision 0 APPENDIX A WATER WELL DATABASE SEARCH INFORMATION 045136 (16) LaSalle Generating Station

TABLE A-1 Page 1 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 80946 - - - 099 32N 05E 01 - E Larson CW Johnson 1924 240 RG DO - -

90947 - - - 099 32N 05E 01 - E Malady CW Johnson 1919 187 RG DO - -

80948 - - - 099 32N 05E 01 - E Malady - 02/02/1934 40 RG DO - -

80949 409 41.276158 88.590021 099 32N 05E 01 - E Farmer CR Johnson 1954 130 RG DO - -

81040 - - - 099 32N 05E 02 - - - 07/01/1856 - C DO - -

81041 - - - 099 32N 05E 02 - - - 08/07/1956 - RG DO - -

80950 - - - 099 32N 05E 02 - WA Graves CW Johnson 02/06/1934 200 RG DO - -

80951 - - - 099 32N 05E 02 - P Kennedy CW Johnson 1913 488 RG DO - -

80953 - - - 099 32N 05E 02 - P Kennedy M Higgins 1919 217 RG DO - -

80954 411 41.273353 88.610301 099 32N 05E 02 - J Talty CW Johnson 1914 560 RG DO - -

364963 27287 41.270599 88.613889 099 32N 05E 02 3B Richard Hamilton #1 Area Well & Pump/Robert 08/17/2004 126 RG DO DL UN 370504 27433 41.272263 88.621201 099 32N 05E 02 6C Ryan Wenzel #1 Area Well & Pump/Robert 05/05/2005 460 RG DO DL BR

- 410 41. 273115 88.624899 - 32N 05E 03 - J Hogg CR Johnson 01/01/2016 276 - - - -

- 1348 41.271497 88.609934 - 32N 05E 03 - T. Fitzgerald Vickery Drilling Co., Inc 12/01/1958 443 - - - -

80952 - - - 099 32N 05E 02 6C P Kennedy - 03/06/1934 488 C DO - -

80956 - - - 099 32N 05E 03 - T Olson CW Johnson 02/07/1934 186 RG DO - -

80955 - - - 099 32N 05E 03 - O Hettle - 02/01/1934 30 RG DO - -

252466 24576 41.268421 88.642872 099 32N 05E 03 - Ronald Neundorf Knierim 12/27/1991 260 RG DO - BR 360563 - - - 099 32N 05E 03 3G Richard & Bernice Dunn John Rix - 16 A DO DU -

81042 22707 41.268493 88.635638 099 32N 05E 03 4A J Triplett D Stoneberger 10/04/1976 172 RG DO - -

81049 24002 41.268469 88.63805 099 32N 05E 03 5A R Terry R Scherf 07/02/1987 60 RG DO - -

81043 2101 41.268421 88.642872 099 32N 05E 03 7A J Purdue JT Anderson 1946 226 RG DO - -

81044 23524 41.268421 88.642872 099 32N 05E 03 7A D White P Knierim 06/23/1980 500 RG DO - -

228247 24269 41.277354 88.647973 099 32N 05E 03 1F Henery Englehurst Knierim 08/30/1990 184 RG DO - UN 320623 26122 41.277321 88.65036 099 32N 05E 04 2F Roger Bols Area Well & Pump 11/27/1999 170 RG DO DL UN 26912 25041 41.280896 88.652853 099 32N 05E 04 3H Ron & Sue Marconi K&K Drilling/Brown 06/10/1995 218 RG DO DL BR 307595 25885 41.268227 88.654873 099 32N 05E 04 4A Thomas Duncan #1 Arrow W&P/Strange 05/02/1998 151 RG DO DL UN 80958 - - - 099 32N 05E 04 4C Lambert - 01/30/1934 226 RG DO - -

346273 26772 41.271838 88.654978 099 32N 05E 04 4C Gary Thorsen #2 Arrow Well & Pump/Mike Strange 09/05/2002 235 RG DO DL UN 80957 - - - 099 32N 05E 04 4E S Barlo Higgins and Bennett 1929 275 RG DO - -

296111 25596 41.279062 88.655185 099 32N 05E 04 4G William Bankowski #1 John Rix 06/03/1997 226 RG DO DL UN 81045 22478 41.275416 88.657471 099 32N 05E 04 53 Abbott Contractors Du Page Pump Inc. 08/21/1974 410 RG IC - -

367155 - - - 099 32N 05E 04 7B IL Dept of Natural Resources Albrecht Drilling/Harold 1982 55 A MO DL -

367154 - - - 099 32N 05E 04 7B IL Dept of Natural Resources Albrecht Drilling/Harold 1983 25 A MO DL -

367156 - - - 099 32N 05E 04 7B IL Dept of Natural Resources Albrecht Drilling/Harold 1984 41 A MO DL -

367157 - - - 099 32N 05E 04 7B IL Dept of Natural Resources Albrecht Drilling/Harold 2003 53 A MO DL -

357158 - - - 099 32N 05E 04 7B IL Dept of Natural Resources Albrecht Drilling/Harold 2003 65 A MO DL -

367159 - - - 099 32N 05E 04 7B IL Dept of Natural Resources Albrecht Drilling/Harold 2003 59 A MO DL -

292392 25477 41.269861 88.664502 099 32N 05E 04 8B Henry Englehaupt K&K Drilling/Brown 12/18/1996 229 RG DO DL UN

- 26983 41.271717 88.662155 - 32N 05E 05 - DNR/National Guard IL State Geological Survey 10/30/2003 55 - - - -

- 26984 41.271717 88.662155 - 32N 05E 06 - DNR/National Guard IL State Geological Survey - - - - - -

- 26985 41.271717 88.662155 - 32N 05E 07 - DNR/National Guard IL State Geological Survey - - - - - -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 2 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 81052 - - - 099 32N 05E 05 5A IL Army Natl Guard - 06/28/1983 18 A DO - -

80961 - - - 099 32N 05E 05 5A VL Briner - 02/05/1934 11 RG DO - -

81046 23319 41.267958 88.671729 099 32N 05E 05 5A Marseilles Training SD Albrecht 06/24/1985 478 RG DO - -

81047 - - - 099 32N 05E 05 5A IL Army Natl Guard Albrecht 1985 478 I DO - -

81048 - - - 099 32N 05E 05 5A State of Illinois - 10/01/1982 18 A DO - -

81050 - - - 099 32N 05E 05 7A IL Army Natl Guard Will Co Well 04/10/1985 239 RG DO - -

81051 - - - 099 32N 05E 05 7A IL Army Natl Guard Will Co Well 1985 239 I DO - -

80960 - - - 099 32N 05E 05 7A OR Bradley Shelton 02/06/1934 45 RG DO - -

80959 - - - 099 32N 05E 05 8E W Maddus - 02/05/1934 22 RG DO - -

- 23318 41.267857 88.681449 - 32N 05E 5 - Naal Plumbing and Heating Co. Rob, Ronald Green 04/10/1985 239 - - - -

80962 - - - 099 32N 05E 06 4G J Jugd - 02/05/1934 28 RG DO - -

81053 23525 41.278765 88.696094 099 32N 05E 06 5G B Laatz C Fykes 06/16/1983 485 RG DO - -

81054 2375 41.280597 88.696127 099 32N 05E 06 5H B Laatz C Fykes 12/12/1972 535 RG DO - -

275805 25104 41.280597 88.696138 099 32N 05E 06 5H Al Vanderslvis RIX 08/28/1995 230 RG DO DL UN 80963 - - - 099 32N 05E 06 6A FN Shaver - 02/05/1934 46 RG DO - -

258325 - - - 099 32N 05E 06 6G Harry Mobes Fordonski 02/21/1994 440 RG DO DL BR 81055 - - - 099 32N 05E 06 7J J Brandon CW Johnnson 1976 232 RG DO - -

80964 - - - 099 32N 05E 07 1 C Gage - 02/05/1934 30 RG DO - -

80965 26467 41.265989 88.686229 099 32N 05E 07 1H C Gage B Irwin 1884 220 RG DO - -

338143 - - - 099 32N 05E 07 1H Larry Gage #2 Aneffco Drilling 10/09/2000 254 RG DO DL UN 80967 - - - 099 32N 05E 07 8D J Kuhn G Henshue 1984 255 RG DO - -

333840 26389 41.258602 88.702806 099 32N 05E 07 8D Gary Miller Arrow Well & Pump 06/18/2001 500 RG DO DL BR 80966 - - - 099 32N 05E 07 8H IN Baughman E Henshue 02/05/1934 191 RG DO - -

- 1744 41.265989 88.686229 - 32N 05E 08 - Gage Byron CR Johnson 01/01/2005 238 - - - -

- 23811 41.263399 88.587263 - 32N 05E 08 - Kruger, Mike RIX 02/24/2000 190 - - - -

80968 - - - 099 32N 05E 08 4H JE Gage CW Johnson 1911 187 RG DO - -

- 26669 41.266163 88.669255 - 32N 05E 09 - Commonwealth Edison - - 171 - - - -

80971 - - - 099 32N 05E 09 1D P Godfrey - 05/09/1958 183 RG DO - -

80972 - - - 099 32N 05E 09 1D P Godfrey - 05/09/1958 183 C DO - -

80969 - - - 099 32N 05E 09 6H HH Streubler - 02/06/1934 55 RG DO - -

80970 - - - 099 32N 05E 09 8A WJ Briner - 02/07/1934 45 RG DO - -

80973 - - - 099 32N 05E 10 - S Duncan J Schomas 1929 238 RG DO - -

80974 412 41.26659 88.645204 099 32N 05E 10 - OTT CW Johnson 1915 232 RG DO - -

80975 - - - 099 32N 05E 10 - Metro Life Ins Co - 02/07/1934 220 RG IC - -

258506 - - - 099 32N 05E 10 8H Winston OBrien Fordonski 09/22/1992 100 RG DO DL BR 368133 27430 41.266578 88.645209 099 32N 05E 10 8H Mike Musser Area Well & Pump/Robert - 120 RG DO DL DH 80976 414 41.264293 88.612509 099 32N 05E 11 - T Crowley CW Johnson 02/06/1934 215 RG DO - -

- 413 41.254342 88.608581 - 32N 05E 11 - Couglin Wm CR Johnson - 235 - - - -

- 1150 41.256064 88.615911 - 32N 05E 11 - Kennedy Mike P - - 335 - - - -

- 1413 41.254825 88.60753 - 32N 05E 11 - - Vickery Drilling Co.,Inc. 06/01/1959 450 - - - -

80977 - - - 099 32N 05E 11 - Schultz E Henshue 1894 200 RG DO - -

80978 - - - 099 32N 05E 12 - E Henry - 02/02/1934 - RG DO - -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 3 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 80979 - - - 099 32N 05E 12 - Talty - 02/15/1934 90 RG DO - -

80980 266 41.258904 88.590634 099 32N 05E 12 - Twohey CR Johnson 1952 19 RG DO - -

346605 26731 41.265314 88.589606 099 32N 05E 12 1G Chadd Baker #1 K&L Well Drilling/Ken 11/16/2002 190 RG DO DL BR 351742 - - - 099 32N 05E 12 1G Chadd Baker - - 147 A - DR -

- 415 41.255267 88.604985 - 32N 05E 12 - Maier Chas CR Johnson - 253 - - - -

80981 - - - 099 32N 05E 13 - C Malady - 02/09/1934 40 RG DO - -

81056 2102 41.243453 88.58892 099 32N 05E 13 1C Kuhn JT Anderson 03/04/1961 113 RG DO - -

81057 2229 41.239459 88.599386 099 32N 05E 13 5A T Sheedy JT Anderson 04/25/1970 180 RG DO - -

80982 - - - 099 32N 05E 14 - M Sheedy CW Johnson 02/15/1934 160 RG DO - -

80983 - - - 099 32N 05E 14 - M Sheedy CW Johnson 1912 240 RG DO - -

81058 23526 41.250706 88.608453 099 32N 05E 14 1G D Bedeker R Scherf 01/12/1983 51 RG DO - -

- 24929 41.247071 88.608322 - 32N 05E 14 - D Bedeker Brown, Darwin 10/15/1994 480 - - - -

80984 - - - 099 32N 05E 15 - Zimmerman CW Johnson 02/14/1934 160 RG DO - -

8095 - - - 099 32N 05E 15 - Peoples Trust Bank CW Johnson 02/14/1934 301 RG IC - -

- 1149 41.239482 88.634918 - 32N 05E 15 - Pfeffer Louis - 01/01/1950 184 - - - -

80986 - - - 099 32N 05E 16 - A Marsh CW Johnson 02/06/1934 300 RG DO - -

252442 - - - 099 32N 05E 16 - IL Dept of Conservation Midwest Well & Pump 1992 665 RG CO - BR

- 24641 41.246273 88.663934 - 32N 05E 16 - Commonwealth Edison Wehling, Richard H 11/02/1992 730 - - - -

- 416 41.25189 88.652082 - 32N 05E 16 - Marsh J J CW Johnson 01/01/1916 265 - - - -

- 22451 41.247326 88.669147 - 32N 05E 17 - Commonwealth Edison Wehling, Well Works Inc 01/01/1974 1692 - - - -

81063 2349 41.239924 88.666233 - 32N 05E 17 - Commonwealth Edison Wehling, Well Works Inc 05/01/1972 1620 - - - -

- 417 41.251483 88.678538 - 32N 05E 17 - Rose A D CW Johnson 01/01/1916 187 - - - -

81059 - - - 099 32N 05E 17 - Con Ed Co - 12/13/1983 411 RG IC - -

81062 - - - 099 32N 05E 17 - Con Ed Co - 04/21/1972 980 C IC - -

80987 - - - 099 32N 05E 17 - Henry - 02/07/1934 38 RG DO - -

80988 - - - 099 32N 05E 17 - IN Baughman E Henshue 02/05/1934 195 RG DO - -

80989 - - - 099 32N 05E 17 - HA Bevington - 02/12/1934 29 RG DO - -

81066 - - - 099 32N 05E 18 - C Alvarado D Santelman 1966 254 RG DO - -

80990 - - - 099 32N 05E 18 - Brookfield Pres Church - 02/12/1934 22 RG SC - -

80991 - - - 099 32N 05E 18 - F Carr CW Johnson 03/26/1905 255 RG DO - -

371414 - - - 099 32N 05E 18 1H Rchard Frye #1 K&K Drilling/Ken Knierim 07/28/2004 540 RG DO DL BR 371567 - - - 099 32N 05E 18 1H Richard Frye John Rix - 180 A DO DL -

258338 - - - 099 32N 05E 18 8C Greg Hil Dober 10/28/1993 300 RG DO DL BR

- 1151 41.240471 88.70228 - 32N 05E 18 - Copp Joseph H - 01/01/1951 - - - - -

- 27445 41.251387 88.685745 - 32N 05E 18 - Richard Frye RIX 07/28/2004 540 - - - -

- 24642 41.238667 88.702219 - 32N 05E 18 - Hill, Randy C R Johnson 09/21/1992 147 - - - -

80992 - - - 099 32N 05E 19 - WG Schutte J Eyer 03/15/1905 293 RG DO - -

80993 - - - 099 32N 05E 19 - LW Laatz - 02/12/1934 320 RG DO - -

81067 - - - 099 32N 05E 19 1A Truman F Osmond Agency CE Woodruff 06/18/1975 231 RG DO - -

816058 - - - 099 32N 05E 19 5D Tri County Well Co C Fykes 04/30/1979 105 RG IC - -

320642 26141 41.231452 88.702109 099 32N 05E 19 8E Scott Duffield #1 Aneffco Drilling 07/14/1999 222 RG DO DL UN

- 22583 41.224183 88.685457 - 32N 05E 19 - Osmond Truman E - 06/01/1975 231 - - - -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 4 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type

- 23527 41.229671 88.694759 - 32N 05E 19 - Fykes, Charles N Tri-County Well and Pump 04/30/1979 105 - - - -

- - - - - 32N 05E 20 - AC Olsen CW Johnson 1908 265 RG DO - -

80995 - - - 099 32N 05E 20 - WT Cordial - 1880 32 RG DO - -

80996 - - - 099 32N 05E 20 - LF Gage - 02/13/1934 288 RG DO - -

80997 - - - 099 32N 05E 20 - D Stevenson E Henshue 1907 188 RG DO - -

294363 25478 41.237118 88.673263 099 32N 05E 20 4H Mike Davis #1 John Rix 01/15/1997 550 RG DO DL BR 81070 - - - 099 32N 05E 21 - Brookfield Township Hall - 1975 500 C IC - -

80998 - - - 099 32N 05E 21 - P Thompson - 02/07/1934 28 RG DO - -

80999 - - - 099 32N 05E 21 - D Kelley CW Johnson 1914 265 RG DO - -

81069 22513 41.227259 88.64606 099 32N 05E 21 2G B Holmes C Fykes 07/25/1974 580 RG DO - -

- 1747 41.227585 88.646545 - 32N 05E 21 Loretta Wolf Bolliger, John And Sons 01/01/1955 206 - - - -

81000 - - - 099 32N 05E 22 - W Spaulding - 02/14/1934 35 RG DO - -

81001 - - - 099 32N 05E 22 - MC Elroy - 02/14/1934 235 RG DO - -

81002 - - - 099 32N 05E 22 - J Mair - 02/14/1934 35 RG DO - -

252483 - - - 099 32N 05E 22 - Barb Spamanto RIX 11/08/1991 94 RG DO - UN 289546 25419 41.237618 88.644597 099 32N 05E 22 8H John Rix #1 RIX 06/10/1996 560 RG DO - -

- 23889 41.238066 88.627085 - 32N 05E 22 - Spaulding, Roy CR Johnson - 130 - - - -

81003 - - - 099 32N 05E 23 - G Darby G Darby 1902 314 RG DO - -

81004 - - - 099 32N 05E 23 - RD Mills CW Johnson 1904 115 RG DO - -

81005 - - - 099 32N 05E 24 - JJ Sheedy - 02/06/1934 625 RG DO - -

81006 - - - 099 32N 05E 24 - TJ Dunn CW Johnson 1904 100 RG DO - -

- 2100 41.235045 88.704548 - 32N 04E 24 - McCormick Clarence - 04/01/1963 255 - - - -

- 24930 41.225211 88.595661 - 32N 05E 24 - Pete Perkins Brown, Darwin 10/06/1994 110 - - - -

81007 - - - 099 32N 05E 25 - JA Ryan CW Johnson 1925 590 RG DO - -

1008 - - - 099 32N 05E 25 - JA Ryan - 12/11/1953 514 RG DO - -

8109 - - - 099 32N 05E 25 - T Green CW Johnson 1919 158 RG DO - -

81010 - - - 099 32N 05E 25 - LR Raseland CW Johnson 1917 560 RG DO - -

81011 - - - 099 32N 05E 25 1D LR Roseland - 03/06/1934 560 C DO - -

81071 - - - 099 32N 05E 25 8H JA Ryan JT Anderson 1922 513 RG DO - -

- 24069 41.223384 88.605324 - 32N 05E 25 - Carry, Robert Scherf Robert William 06/11/1988 50 - - - -

- 2103 41.223384 88.605324 - 32N 05E 25 - Ryan A J - 10/01/2002 514 - - - -

81012 - - - 099 32N 05E 26 - N Welch CW Johnson 1911 220 RG DO - -

81013 - - - 099 32N 05E 26 - N Welch - - 210 RG DO - -

81014 - - - 099 32N 05E 26 - JH Divine CW Johnson 1919 224 RG DO - -

81015 - - - 099 32N 05E 27 - EA Morrow - - 112 RG DO - -

81018 - - - 099 32N 05E 27 - E Morrow CW Johnson 02/16/1934 112 RG DO - -

81016 - - - 099 32N 05E 27 3H EA Morrow - 05/28/1952 112 C DO - -

81017 - - - 099 32N 05E 27 3H E Morrow - 06/04/1952 112 C DO - -

81019 - - - 099 32N 05E 28 - RW Debolt E Henshue 1894 214 RG DO - -

81020 - - - 099 32N 05E 28 - MW OLaughlin J Eyre 1896 258 RG DO - -

81072 - - - 099 32N 05E 29 - Department of Conservation - 12/24/1985 16 A IC - -

81021 - - - 099 32N 05E 29 - CS Tryon E Henshue 02/13/1934 187 RG DO - -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 5 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 81022 - - - 099 32N 05E 29 - J Widman - 02/12/1934 56 RG DO - -

81023 - - - 099 32N 05E 29 - CA Widman CW Johnson 1919 167 RG DO - -

81073 - - - 099 32N 05E 29 - Department of Conservation - 12/24/1985 10 A IC - -

320636 26135 41.211574 88.682007 099 32N 05E 29 8B Ron Widman #1 K&K Drilling 05/04/1999 184 RG DO - -

- 26800 41.220594 88.698294 - 32N 05E 30 - Alan V. Anderson RIX 08/22/2002 - - - - -

- 1748 41.213692 88.694654 - 32N 05E 30 - Egeland Elmer - 01/01/1950 - - - - -

09964345 - - - 099 32N 05E 16 8E IDNR LaSalle Fish Hathery WEHLING WELL WORK 1992 770 D - - BR 09914770 - - - 099 32N 05E 16 8E Exelon - LaSalle Co Station - - - - - - -

- 2357 41.339624 88.704918 - 33N 05E 7 - City of Marseilles Miller, J. P. Art. Well 01/01/1972 1466 - - - -

- 473 41.339471 88.679184 - 33N 05E 8 - Fewel Howard - - 197 - - - -

- 2218 41.339855 88.705654 - 33N 05E 12 - Peters Wm Mrs CR Johnson 01/01/1970 198 - - - -

81732 - - - 099 33N 05E 15 - L Brei - 02/01/1934 18 RG DO - -

260864 24890 41.337146 88.633015 099 33N 05E 15 - Gerald Hubbard Lockport Well & Pump 07/12/1994 145 RG DO DL BR 81802 - - - 099 33N 05E 15 ID OO Johnson TF Anderson 1902 165 RG DO - -

81803 - - - 099 33N 05E 15 IH S Betz J Knierim 03/21/1977 360 RG DO - -

81733 - - - 099 33N 05E 16 - BF Biba - 1894 35 RG DO - -

81734 - - - 099 33N 05E 16 - S Anderson C Anderson 1911 425 RG DO - -

81735 664 41.325218 88.66409 099 33N 05E 16 - HR Smith JP Miller 1940 140 RG DO - -

231218 24465 41.338642 88.663392 099 33N 05E 16 - Ken Johnson #2119 Dober 06/10/1991 378 RG DO - BR 81804 23629 41.333316 88.650942 099 33N 05E 16 1E YMCA C Fykes 08/12/1977 325 RG DO - -

81736 663 41.338761 88.651171 099 33N 05E 16 1H C Brei JT Anderson 09/16/1950 365 RG DO - -

259502 - - - 099 33N 05E 16 2H John Ferguson K&K Drilling/Brown 09/01/1994 320 RG DO DL BR 296110 25608 41.335023 88.660781 099 33N 05E 16 5F Whispering Pines Campground #2 Arrow W&P/M Strange 04/12/1997 360 RG NC DL BR 293051 25508 41.33867 88.660948 099 33N 05E 16 5H Keith Maloney #1 John Rix 09/12/1996 380 RG DO DL BR 81805 - - - 099 33N 05E 16 5H WP Hardin C Fykes 01/30/1976 405 RG DO - -

329585 - - - 099 33N 05E 16 6A Mike & Debra Wheeler #1 Arrow Well & Pump 07/31/2000 360 RG DO DL BR 279914 25189 41.325873 88.662791 099 33N 05E 16 6A Paul Borgarding Fordonski 10/30/1995 305 RG CS DL BR 258128 - - - 099 33N 05E 16 6C Shane Marik Fordonski 08/27/1993 50 RG DO DL UN 289558 25426 41.331346 88.66305 099 33N 05E 16 6D Wesley Ness Comar Drilling 05/22/1996 300 RG DO DL BR 280597 25138 41.33317 88.663134 099 33N 05E 16 6E Steve & Tiffany Wheeler K&K Drilling/Brown 10/26/1995 320 RG DO DL BR 320627 26126 41.334993 88.663221 099 33N 05E 16 6F Don Dudek #1 Arrow Well & Pump 04/28/1999 360 RG DO DL BR 378434 27641 41.327656 88.665288 099 33N 05E 16 7B Frank Carajohn Will County Well & Pump/Steve 02/10/2006 340 RG DO DL BR 334602 25607 41.338612 88.665837 099 33N 05E 16 7C Kenneth Sangston #1 Arrow Well & Pump 08/22/2001 360 RG DO DL BR 346609 26735 41.32949 88.665399 099 33N 05E 16 7C Bryan & Lanette Strum #1 Arrow Well & Pump/Mike Strange 01/30/2003 380 RG DO DL BR 265573 24982 41.32949 88.665399 099 33N 05E 16 7C Len Peretta K&K Drilling/Brown 01/22/1995 320 RG DO DL BR 265374 24966 41.327667 88.661253 099 33N 05E 16 7C John Kennedy K&K Drilling/Brown 12/17/1994 340 RG DO DL BR 4576875 26156 26156 41.331316 099 33N 05E 16 7D Daniel Warning Lockport Well & Pump 10/09/1999 350 RG DO DL BR 307596 25898 41.331316 88.665487 099 33N 05E 16 7D Jim Hovious #1 Arrow W&P/Strange 06/04/1998 340 RG DO DL BR 262801 24939 41.331316 88.665487 099 33N 05E 16 7D Mark & Fawn Rohwer K&K Drilling/Brown 10/05/1994 317 RG DO DL BR 275833 25108 41.33314 88.665574 099 33N 05E 16 7E Carol & Janice Richards K&K Drilling/Brown 09/07/1995 340 RG DO DL BR 346258 26762 41.334966 88.665662 099 33N 05E 16 7F Steve Brown #1 Arrow Well & Pump/Mike Strange 08/21/2002 360 RG DO DL BR 373124 27500 41.334954 88.665638 099 33N 05E 16 7F Leo Trompeter #1 Arrow Well & Pump/Mike Strange 06/08/2005 360 RG DO DL BR CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 6 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type

- 26399 41.3294 88.665399 - 33N 05E 16 - Sangston, Kenneth and Jennife Strange, Michael 08/22/2001 360 - - - -

- 26322 41.325873 88.662791 - 33N 05E 16 - Wheeler, Mike and Debra Strange, Michael 07/31/2000 360 - - - -

356888 27034 41.336789 88.665749 099 33N 05E 17 7G Rich Humphrup Area Well & Pump/Robert 09/24/2003 360 RG DO DL BR 361125 27171 41.336789 88.665749 099 33N 05E 16 7G Mike Stropoli #1 Arrow Well & Pump/Mike Strange 04/24/2003 360 RG DO DL BR 327574 26252 41.336789 88.665749 099 33N 05E 16 7G Johnathan Mavec Tri County W&P 11/07/2000 360 RG DO BD BR 294359 25507 41.336789 88.665749 099 33N 05E 16 7G Tim Knott K&K Drilling/Brown 04/09/1997 400 RG DO DL BR 81806 662 41.33861 88.665822 099 33N 05E 16 7H S Anderson CJ Anderson 12/02/1909 417 RG DO - -

296114 - - - 099 33N 05E - 7H Ralph Sanders SCCountry W&P/Brian 06/12/1997 340 RG DO DL BR 332235 26335 41.32946 88.667832 099 33N 05E 16 8C Steve & Sydney Ferris K&K Drilling 05/20/2001 400 RG DO DL BR 334601 26398 41.331286 88.667923 099 33N 05E 16 8D Mark Kirkton #1 K&K Drilling 07/02/2001 400 RG DO DL BR 359110 27116 41.331286 88.667923 099 33N 05E 16 8D Fawn Rohwer #1 Arrow Well & Pump/Mike Strange 08/16/2003 360 RG DO DL BR 311575 25951 41.334936 88.668102 099 33N 05E 16 8F Brad Kaluzna K&K Drilling/Knierim 02/24/1999 360 RG DO DL BR 303322 25758 41.338585 88.668281 099 33N 05E 16 8H Jerry Popplewell #1 AC Drilling/Leasure 02/01/1998 320 RG DO DL BR 27995 25190 41.338585 88.668281 099 33N 05E 16 8H Barry Underwood Fordonski 10/26/1995 320 RG DO DL BR 268803 25032 41.338585 88.668281 099 33N 05E 16 8H Mike Delaurentis K&K Drilling/Brown 06/07/1995 320 RG DO DL BR 269125 25045 41.338585 88.668281 099 33N 05E 16 8H Allen Judd K&K Drilling/Brown 05/20/1995 340 RG DO DL BR

- 25607 41.338612 88.665837 - 33N 05E 16 - Sanders, Ralph and Laurel Bisping, Calvin 06/12/1997 340 - - - -

- 26422 41.334993 88.663221 - 33N 05E 16 - Whispering Pines MHP - 01/01/1974 460 - - - -

81737 - - - 099 33N 05E 17 - W Stebbins - 1884 23 RG DO - -

81738 665 41.328542 88.683529 099 33N 05E 17 - F Kellerman CR Johnson 1946 171 RG DO - -

336428 26413 41.329447 88.670261 099 33N 05E 17 1C Larry Machaj Area Well 7 Pump 07/16/2001 320 RG DO DL BR 320629 26128 41.33127 88.670349 099 33N 05E 17 1D W Mark Rohwer, Jr. #1 Arrow Well & Pump 07/08/1999 360 RG DO DL BR 362818 27238 41.336746 88.670619 099 33N 05E 17 1G Tim & Debby Perry #1 Arrow Well & Pump/Mike Strange 08/05/2004 141 RG DO DL UN 81807 23631 41.338569 88.670707 099 33N 05E 17 1H F Hogue P Knierim 11/26/1982 360 RG DO - -

341724 26646 41.33127 88.672767 099 33N 05E 17 2D Scott & Michelle Campbell #1 Area Well & Pump/Robert 04/25/2002 400 RG DO DL BR 320646 26145 41.338566 88.673118 099 33N 05E 17 2H Stan & Heidi Henry #1 Aroow Well & Pump 06/11/1999 340 RG DO DL BR 269121 25046 41.338566 88.673118 099 33N 05E 17 2H Iris Denham K&K Drilling/Brown 05/25/1995 340 RG DO DL BR 285581 25328 41.33856 88.677936 099 33N 05E 17 2H Steve Cooke Comar Drilling 09/08/1995 300 RG DO DL BR 286521 25228 41.338566 88.673118 099 33N 05E 17 2H Eric Denham K&K Drilling/Brown 02/15/1996 340 RG DO DL BR 258350 - - - 099 33N 05E 17 3G Steven Cooke K&K Drilling/Brown 11/21/1993 300 RG DO DL BR 262891 24940 41.325806 88.677354 099 33N 05E 17 4A Dave Raikes Fordonski 08/23/1994 200 RG DO DL BR 258324 24916 41.338566 88.6731118 099 33N 05E 17 4H Janelle Denham K&K Drilling/Brown 03/15/1994 340 RG DO DL BR 300261 25699 41.33856 88.677936 099 33N 05E 17 4H Wayne Nogue Comar Drilling/Jeff 09/18/1997 300 RG DO DL BR 280556 25139 41.33856 88.677936 099 33N 05E 17 4H Arvin Tongate Fordonski 09/18/1995 320 RG DO DL BR 348496 - - - 099 33N 05E 17 4H Sam Candela K&K Drilling/Jeff Hieser 04/10/2003 420 RG DO DL BR 310118 25973 41.333093 88.680102 099 33N 05E 17 5E Jerry Sebby K&K Drilling/Knierim 05/07/1999 400 RG DO DL BR 342718 26591 41.336737 88.682678 099 33N 05E 17 6G Henry Nellett Comar Drilling/Juan 03/12/2002 320 RG DO DL BR 374678 27580 41.333083 88.68491 099 33N 05E 17 7E Kyle Cepaitis Mike Strange/Arrow Well & Pump 10/25/2005 360 RG DO DL BR 325880 26225 41.333093 88.684935 099 33N 05E 17 7E Kevin Gill Area Well & Pump 07/14/2000 260 RG DO DL BR 228252 24297 41.334913 88.685012 099 33N 05E 17 7F Harry Keine Knierim 07/26/1990 150 RG DO - BR 81808 23630 41.339326 88.684271 099 33N 05E 17 7H Glenwood Farms P. Knierim 06/12/1979 380 RG IC - -

372993 27501 41.338542 88.685144 099 33N 05E 17 7H Sally Spencer #1 Arrow Well & Pump/Mike Strange 07/10/2005 320 RG DO DL BR CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 7 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type

- 26934 41.33856 88.673679 - 33N 05E 17 - Candela, Sam Brown, Darwin 04/10/2003 420 - - - -

- 26505 41.338551 88.687577 - 33N 05E 17 - Glenwood RV Resort - - - - - - -

- 1111 41.333093 88.684931 - 33N 05E 17 - Martin Morey - 01/01/1953 250 - - - -

- 246 41.33355 88.680726 - 33N 05E 17 - - - - - - - - -

81739 - - - 099 33N 05E 18 - RG Hinch E Henshue 1925 165 RG DO - -

81809 2210 41.337529 88.690567 099 33N 05E 18 1G D Danielson CE Woodruff 04/07/1970 270 RG DO - -

- 1261 41.326733 88.695538 - 33N 05E 18 - Littlefair - 01/01/1954 - - - - -

- 245 41.331733 88.694243 - 33N 05E 18 - - - - - - - - -

81740 - - - 099 33N 05E 19 - CF Berry J Henshue 1914 200 RG DO - -

81741 - - - 099 33N 05E 19 - F Shultz E Henshue 1900 177 RG DO - -

81742 666 41.314103 88.696659 099 33N 05E 19 - EJ Lattz CE Woodruff 1944 210 RG DO - -

265364 24983 41.316791 88.698171 099 33N 05E 19 5D Kelly Rarden K&K Drilling/Brown 01/24/1995 180 RG DO DL BR 305145 25824 41.316791 88.698171 099 33N 05E 19 5D James J Cuchiarn Area W&P/Strange 08/19/1998 220 RG DO DL BR 301797 25759 41.314988 88.700379 099 33N 05E 19 6C George Votava K&K Drilling/Knierim 01/21/1998 180 RG DO DL BR 359111 27104 41.318603 88.703201 099 33N 05E 19 7E Robert Satler #1 Arrow Well & Pump/Mike Strange 11/09/2003 260 RG DO DL BR 298819 25700 41.322212 88.703605 099 33N 05E 19 7G Charles Allen #2 Aneffco Dlg/Efflandt 10/16/1997 203 RG DO DL BR

- 1147 41.31684 88.700585 - 33N 05E 19 - Hayes J H - 01/01/1953 210 - - - -

- 1259 41.317737 88.697066 - 33N 05E 19 - Wise Wm Woodruff Charles Co 01/01/1942 82 - - - -

81743 - - - 099 33N 05E 20 - F Hobart - 1840 35 RG DO - -

81744 - - - 099 33N 05E 20 - J Mitchell J Henshue 1902 95 RG DO - -

346256 26766 41.322216 88.672306 099 33N 05E 20 2G Jeff & Tina Kiper #1 Arrow Well & Pump/Mike Strange 10/02/2002 240 RG DO DL BR 326698 26204 41.320429 88.674588 099 33N 05E 20 3F Jim Dowling K&K Drilling 10/26/2000 220 RG DO DL BR 322068 26031 41.320429 88.674588 099 33N 05E 20 3F Cecil Lee Lockport Well & Pump 02/15/2000 305 RG DO DL BR 285589 25329 41.320429 88.674588 099 33N 05E 20 3F Michael Shelton Comar Drilling 10/23/1995 200 RG DO DL BR 331057 26295 41.322214 88.674709 099 33N 05E 20 3G Christian Campa Will County Well & Pump 03/09/2001 201 RG DO DL BR 81810 22953 41.317799 88.675951 099 33N 05E 20 4E IL Nitrogen Wehling Well Works 07/14/1977 360 RG IC - -

81811 - - - 099 33N 05E 20 4E IL Nitrogen - 07/19/1977 360 C IC - -

- 1116 41.317733 88.677956 - 33N 05E 20 - Trumbo Riley Woodruff Charles Co 01/01/1952 158 - - - -

- 232 41.316402 88.676085 - 33N 05E 20 - unknown unknown - unknown - - - -

- 248 41.320456 88.667407 - 33N 05E 21 - unknown unknown - unknown - - - -

81821 - - - 099 33N 05E 21 - Natl Phosphate Co WC Johnson 1894 175 A IC - -

81822 - - - 099 33N 05E 21 - Baker Industries Co - 04/08/1979 583 C IC - -

81745 - - - 099 33N 05E 21 - Spicer - 1933 12 RG DO - -

81746 - - - 099 33N 05E 21 - K Keller J Henshue 1894 175 RG DO - -

81812 - - - 099 33N 05E 21 - Natl Phopshate Co - - 583 RG IC - -

81813 - - - 099 33N 05E 21 - Natl Phosphate Co Layne Western 1961 427 RG IC - -

81814 - - - 099 33N 05E 21 - Natl Phosphate Co Layne Wetern 12/22/1961 421 RG IC - -

81815 - - - 099 33N 05E 21 - Natl Phosphate Co Layne Western 1961 421 RG IC - -

379750 - - - 099 33N 05E 21 1H Steve Flynn #6 Steve Flynn - 60 A DO DL -

379751 - - - 099 33N 05E 21 1H Steve Flynn #7 Steve Flynn - 50 A DO DL -

379744 - - - 099 33N 05E 21 2E Steve Flynn #1 Steve Flynn - 20 A DO DL -

379745 - - - 099 33N 05E 21 2E Steve Flynn #2 Steve Flynn - 20 A DO DL -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 8 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 81820 - - - 099 33N 05E 21 3B Natl Phosphate Co - 02/18/1965 583 C 1C - -

81817 - - - 099 33N 05E 21 3D Natl Phosphate Co - 01/13/1961 583 C 1C - -

81818 - - - 099 33N 05E 21 3D Natl Phosphate Co - 12/13/1961 427 C 1C - -

81819 - - - 099 33N 05E 21 3D Natl Phosphate Co - 02/18/1965 583 C 1C - -

379746 - - - 099 33N 05E 21 3H Steve Flynn #3 Steve Flynn - 70 A DO DL -

379747 - - - 099 33N 05E 21 3H Steve Flynn #4 Steve Flynn - 120 A DO DL -

379749 - - - 099 33N 05E 21 3H Steve Flynn #5 Steve Flynn - 105 A DO DL -

275821 25124 41.318759 88.657615 099 33N 05E 21 4E Waste Recovery ILL #3620 Albrecht 04/06/1995 130 RG IC DL BR 310654 25974 41.318759 88.657615 099 33N 05E 21 4E JW Peters & Sons Inc Tri County Well & Pump/Cleary 05/12/1999 240 RG IC DL BR 81823 2063 41.320549 88.657681 099 33N 05E 21 4F WR Woodin TF Anderson 1938 55 RG DO - -

81816 1605 41.316221 88.655923 099 33N 05E 21 5B Natl Phosphate Co Layne Western 1961 583 RC IC - -

279911 - - - 099 33N 05E 21 5E Wste Recovery - IL Dietzman 10/05/1995 400 RG NC DL BR

- 1117 41.318759 88.6576 - 33N 05E 21 - Seymour H H Woodruff Charles Co 01/01/1955 165 - - - -

- 25191 41.31874 88.660044 - 33N 05E 21 - Waste Recovery ILL Dietzman 10/05/1995 400 - - - -

- 248 41.320456 88.667407 - 33N 05E 21 - - - - - - - - -

237015 24678 41.31987 88.634594 099 33N 05E 22 - Mike Close Tri County Well & Pump 06/05/1992 365 RG DO - BR 81747 - - - 099 33N 05E 22 - Wheeler J Henshue 1904 162 RG DO - -

81748 - - - 099 33N 05E 22 - R Shaver Venzain 1914 215 RG DO - -

286455 - - - 099 33N 05E 22 1D John Lamb #1 RIX 02/27/1996 110 RG DO DL UN 309113 25917 41.322602 88.631125 099 33N 05E 22 IG Seneca Twp High School #1 K&K Drilling/Knierim 03/03/1999 440 RG SC DL BR 81824 23632 41.324404 88. 631238 099 33N 05E 22 1H Tri County Well Co C Fykes 08/24/1979 425 RG IC - -

287608 - - - 099 33N 05E 22 2F Katherine Bartkus #1 Neely 07/20/1994 360 RG DO DL BR 304663 25788 41.313555 88.635446 099 33N 05E 22 3B John Bartkus AC Drilling/Leasure 02/12/1998 340 RGP DO DL BR 304664 25975 41.313531 88.637886 099 33N 05E 22 4B John Bartus #1 AC Drilling/Leasure 02/02/1998 360 RG DO DL BR 310649 25388 41.32078 88.633434 099 33N 05E 22 4B John Bartus #1 AC Drilling/Leasure 02/02/1998 360 RG DO DL BR 252446 - - - 099 33N 05E 22 6C Clyde Collins Tri Co Well & Pump 08/16/1992 230 RG DO - BR 81825 2064 41.320638 88.647979 099 33N 05E 22 8F Spicer Gravel Co JT Anderson 09/08/1944 140 RG IC - -

- 25787 41.313531 88.637886 - 33N 05E 22 - Bartkus, John Arthur C. Leasure 02/02/1998 360 - - - -

- 14 41.316181 88.642907 - 33N 05E 22 - Shaver, Roy Zezain Bros 01/01/2016 101 - - - -

81751 - - - 099 33N 05E 23 - LA Butterfield Bennett 1915 113 RG DO - -

81752 667 41.316455 88.617374 099 33N 05E 23 - C Gettler CW Woodruff 1946 68 RG DO - -

81753 - - - 099 33N 05E 23 - C Santa CR Johnson - 60 RG DO - -

81749 - - - 099 33N 05E 23 - AL Irwin Higgins and Bennett 1917 175 RG DO - -

230920 24580 41.318233 88.619919 099 33N 05E 23 - Kevin Thomas Strange 03/07/1991 225 RG DO - BR 321615 26041 41.322855 88.61171 099 33N 05E 23 1G Alan Wilson/Lambert K&K Well Drilling 09/10/1999 440 RG DO DL BR 81750 - - - 099 33N 05E 23 1G AL Irwin - 01/24/1934 175 C DO - -

322219 25993 41.324665 88.611825 099 33N 05E 23 1H Jay Hendrix K&K Well Drilling 02/17/2000 420 RG DO DL BR 81826 2318 41.322823 88.614136 099 33N 05E 23 2G R Rex P Knierim 1972 108 RG DO - -

- 26175 41.324633 88.614255 099 33N 05E 23 2H Tony Centracchio K&K Drilling 05/24/2000 380 RG DO DL BR 346272 26756 41.324633 88.614255 099 33N 05E 23 2H Bill Longtin #1 K&K Well Drilling/Ken 10/23/2002 520 RG DO DL BR 81831 22515 41.313759 88.615986 099 33N 05E 23 3B D Fessler C Fykes 07/12/1974 125 RG DO - -

292378 25509 41.317344 88.618647 099 33N 05E 23 4D Joe Roas Comar Drilling 11/22/1996 340 RG DO DL BR CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 9 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 280561 25140 41.317344 88.618647 099 33N 05E 23 4D Charles Ozze Fordonski 08/30/1995 350 RG DO DL BR 298816 25701 41.317315 88.621072 099 33N 05E 23 5D Smith Builders Tri County W&P/Brian 10/09/1997 300 RG DO DL BR 81827 - - - 099 33N 05E 23 5F R Anderson K Knierim 11/08/1978 260 RG DO - -

81828 795 41.319858 88.626072 099 33N 05E 23 7E Fritz Muffler CE Woodruff 09/16/1970 310 RG IC - -

81829 23353 41.320862 88.626158 099 33N 05E 23 7F R Stieben C Fykes 08/06/1985 345 RG DO - -

320645 26144 41.320862 88.626158 099 33N 05E 23 7F Jerry Morganflash #1 Arrow Well & Pump 06/08/1999 360 RG DO DL BR 352637 - - - 099 33N 05E 23 7F Steve & Fay Davis Mike Strange - 200 A - DL -

346255 26765 41.320862 88.626158 099 33N 05E 23 7F Steve & Fay Davis #2 Arrow Well & Pump/Mike Strange 06/29/2002 360 RG DO DL BR 81832 23898 41.324814 88.626528 099 33N 05E 23 7H L Hobbs Neely 06/07/1986 410 RG DO - -

309114 25918 41.319031 88.628471 099 33N 05E 23 83 Jeff & Pat Cumming #1 K&K Drilling/Knierim 03/01/1999 380 RG DO DL BR 366500 27267 41.319031 88.628471 099 33N 05E 23 8E Larry & Sue Gates Lockport Well & Pump/Dan Gibson 10/25/2004 340 RG DO DL BR 338156 26454 41.322632 88.6287 099 33N 05E 23 8G Ross Rod #1 Arrow Well & Pump 08/24/2001 400 RG DO DL BR 81830 2065 41.322632 88.628689 099 33N 05E 23 8G G Appleby JT Anderson 05/13/1960 180 RG DO - -

81833 23633 41.32443 88.628816 099 33N 05E 23 8H Tri County Well Co C Fykes 12/20/1978 365 RG IC - -

- 25372 41.319031 88.628471 - 33N 05E 23 - Lamb, John 1 RIX 02/27/1996 110 - - - -

- 2418 41.323744 88.612982 - 33N 05E 23 - Kelly Dave Lockport Well & Pump/Dan Gibson 07/01/1973 390 - - - -

- 25372 41.319031 88.628471 - 33N 05E 23 - Lamb, John 1 RIX 02/27/1996 110 - - - -

- 668 41.318233 88.619915 - 33N 05E 23 - Santa Charles CR Johnson 01/01/1945 61 - - - -

- 25068 41.323643 88.611645 - 33N 05E 23 - Seneca, Village of #3 Layne-Western Co. 08/31/1993 1445 - - - -

- 24152 41.324665 88.611825 - 33N 05E 23 - Smith, Mike Knierim, Phil 08/12/1988 400 - - - -

- 1115 41.317317 88.621068 - 33N 05E 23 - Thompson Josephine Woodruff Charles Co 01/01/1952 252 - - - -

- 240 41.318304 88.613825 - 33N 05E 23 - Wilmington Coal Co - - - - - - -

81754 670 41.318531 88.600486 099 33N 05E 24 - S Sampson CR Johnson 1946 65 RG DO - -

341260 26642 41.319499 88.596892 099 33N 05E 24 3E Frank Vicich Area Well & Pump/Bob Strange 02/19/2002 240 RG DO DL BR 237058 24603 41.312201 88.59889 099 33N 05E 24 4A Larry Marco Fordonski 07/17/1992 245 RG DO - BR 344489 26809 41.317641 88.599214 099 33N 05E 24 4D Dave Fessler Area Well & Pump/Robert 08/27/2002 240 RG DO DL BR 304657 25789 41.317596 88.601647 099 33N 05E 24 5D Seneca Twp High School #3898 Albrecht Dlg/Harold 02/09/1998 614 RG IR DL BR 359112 27105 41.324846 88.602086 099 33N 05E 24 5H Kevin Kiper #1 Arrow Well & Pump/Mike Strange 12/23/2003 235 RG DO DL BR 367913 27390 41.322961 88.604206 099 33N 05E 24 6G Merle & Irene Koehler Area Well & Pump/Robert 12/29/2004 260 RG DO DL BR

- 669 41.322353 88.606808 - 33N 05E 24 - Kinner V B - 01/01/1942 326 - - - -

- 671 41.316014 88.609527 - 33N 05E 24 - Seneca City Miller, J.P. Art Well 01/01/1943 704 - - - -

- 15 41.316105 88.609552 - 33N 05E 24 - Seneca City Well Heflin J C 01/01/1927 700 - - - -

- 26506 41.312286 88.594036 - 33N 05E 24 - Seneca Hunt Club - - - - - - -

- 24298 41.313889 88.606282 - 33N 05E 24 - Wheeler, Bob Knierim Phil 06/15/1990 240 - - - -

- 26423 41.312243 88.596461 - 33N 05E 24 - Wildlife MHP - 01/01/1972 - - - - -

- 1764 41.318531 88.600486 - 33N 05E 24 - - CRI and PR Co. 01/01/2005 450 - - - -

- 22956 41.321043 88.606068 - 33N 05E 24 - - K and K Paul Knierim - 260 - - - -

237119 24679 41.310484 88.593943 099 33N 05E 25 2H Scott Mann Knierim 10/15/1992 160 RG DO - BR 258105 24816 41.304999 88.600938 099 33N 05E 25 5E Willard Weinlich Rix Well & Pump 04/16/1994 260 RG DO DL BR 81834 23634 41.297147 88.605995 099 33N 05E 25 7A Anchor Inmaring Inc P Knierim 04/27/1981 35 RG IC - -

256991 - - - 099 33N 05E 25 7H D&S Const. K&K Drilling/Brown 01/06/1994 145 RG DO DL BR 81835 - - - 099 33N 05E 25 8A J Brookman C Johnson 1977 32 RG DO - -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 10 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type

- 26507 41.297148 88.602974 - 33N 05E 25 - Black Marine Inc. Campground - - - - - - -

- 154 41.308676 88.59882 - 33N 05E 25 - Chi'Go Bridge and Iron Geiger, S.B. and Son 01/01/1942 451 - - - -

- 153 41.30869 88.598088 - 33N 05E 25 - Chi'Go Bridge and Iron Geiger, S.B. and Son 01/01/1942 1447 - - - -

- 155 41.303678 88.597931 - 33N 05E 25 - Chi'Go Bridge and Iron Miller, J.P. Art Well 01/01/1943 654 - - - -

- 1260 41.298727 88.601817 - 33N 05E 25 - Hay J-Barge Plant Woodruff Charles Co - 196 - - - -

- 156 41.308449 88.608386 - 33N 05E 25 - Johnson Chas Wm - - 410 - - - -

- 26857 41.309365 88.607222 - 33N 05E 25 - Seneca Elem. School Whitney and Associates - 16 - - - -

- 26858 41.309365 88.607222 - 33N 05E 25 - Seneca Elem. School Whitney and Associates - 16 - - - -

- 26860 41.309365 88.607222 - 33N 05E 25 - Seneca Elem. School Whitney and Associates - 16 - - - -

- 26861 41.309365 88.607222 - 33N 05E 25 - Seneca Elem. School Whitney and Associates - 16 - - - -

- 672 41.304127 88.599684 - 33N 05E 25 - Wicks Arthur CR Johnson - 65 - - - -

81755 - - - 099 33N 05E 26 - AB Clark C Johnson 1919 35 RG DO - -

81756 - - - 099 33N 05E 26 - Hochstatler - 02/01/1934 43 RG DO - -

360557 - - - 099 33N 05E 26 ID Eric & Jessica Wennberg K&K Drilling/Darwin - 24 A DO DL -

367903 27380 41.297869 88.61497 099 33N 05E 26 3A Jack Cunningham #1 Area Well & Pump/Robert 07/27/2004 42 RG DO DL UN 268589 25030 41.297473 88.627089 099 33N 05E 26 8A James Thorpe Fordonski 04/17/1995 50 RG DO DL UN

- 673 41.306633 88.610706 - 05E 26 - Sampson Arthur CR Johnson 01/01/1946 65 - - - -

- 674 41.304099 88.609715 - 33N 05E 26 - Wheeler, James CR Johnson 01/01/1946 65 - - - -

81757 - - - 099 33N 05E 27 - A Tautz A Tautz 1907 18 RG DO - -

81758 - - - 099 33N 05E 27 - HJ Mayer - 01/26/1934 200 RG DO - -

81759 - - - 099 33N 05E 27 - E Mayer - 01/26/1934 25 RG DO - -

237024 24588 41.297438 88.629499 099 33N 05E 27 1A Spring Brook Marina Fordonski 01/23/1992 44 RG IC - BR 264250 - - - 099 33N 05E 27 1A Kevin Steep Fordonski 04/11/1994 230 RG DO DL BR 293045 25510 41.297398 88.631898 099 33N 05E 27 2A J Thorpe Comar Drilling 07/11/1996 45 RG IC DL UN 286517 25217 41.297161 88.646311 099 33N 05E 27 8A Robert Shufflebocham K&K Drilling/Brown 01/11/1996 280 RG DO DL BR

- 26424 41.297199 88.643908 - 33N 05E 27 - Marseilles - 01/01/2000 1450 - - - -

- 26508 41.298971 88.646376 - 33N 05E 27 - Spring Brook Marina - - - - - - -

81760 - - - 099 33N 05E 28 - Hinch Trumbo and Lewis - 01/26/1934 725 RG DO - -

310650 25976 41.304324 88.656231 099 33N 05E 28 4E City of Marseilles Meadow Equip/Kerry 05/19/1998 260 RGS CS DL BR

- 1148 41.303405 88.657398 - 33N 05E 28 - Chiney Elizabeth - 01/01/1955 250 - - - -

- 24775 41.309809 88.649174 - 33N 05E 28 - Fox River Minerals Fordonski 09/17/1992 40 - - - -

- 26425 41.304324 88.656231 - 33N 05E 28 - Marseilles - 01/01/1997 1450 - - - -

81761 - - - 099 33N 05E 29 - S Johnson J Henshue 1904 115 RG DO - -

81762 - - - 099 33N 05E 29 - C Thompson - 01/26/1934 14 RG DO - -

359113 27106 41.305935 88.685239 099 33N 05E 29 8F Matt Bruno #1 Arrow Well & Pump/Mike Strange 10/07/2003 240 RG DO DL BR

- 1765 41.304129 88.685148 - 05E 29 - Bruno Joe - 01/01/1955 134 - - - -

81763 - - - 099 33N 05E 30 - F Schultz G Defenbaugh 1931 201 RG DO - -

81765 - - - 099 33N 05E 30 - VL Briner J Hensue 01/26/1934 231 RG DO - -

379103 - - - 099 33N 05E 30 4D Michael Chase Tri County Well & Pump/Steve 03/30/2006 320 RG DO DL BR 364954 27278 41.30055 88.697118 099 33N 05E 30 5C Rick Schomas #1 K&K Drilling/Ken Knierim 06/16/2004 340 RG DO DL BR 311576 25952 41.30055 88.697118 099 33N 05E 30 5C John Leininger Comar Drilling/Rix W&P 04/17/1999 400 RG DO DL BR 334621 26410 41.305961 88.697303 099 33N 05E 30 5F Premiers Asset Services #1 Arrow Well & Pump 08/27/2001 999 RG IC DL ~

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 11 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 350162 27018 41.30056 88.699531 099 33N 05E 30 6C Steven Kent #1 K&K Drilling/Ken Knierim 06/10/2003 340 RG DO DL BR 237066 24680 41.302372 88.702008 099 33N 05E 30 7D Pete Witkowski Tri County Well/Pump 11/28/1992 320 RG DO - BR 81764 - - - 099 33N 05E 30 7G F Schultz - 01/30/1934 201 C DO - -

- 1579 41.221726 88.584727 - 33N 05E 30 - Perry Joe - 08/01/1953 114 - - - -

- 233 41.307883 88.699782 - 33N 05E 30 - - - - - - - - -

- 234 41.308358 88.702812 - 33N 05E 30 - - - - - - - - -

81836 - - - 099 33N 05E 31 4A J Jungles C Johnson 1976 180 RG DO - -

81766 - - - 099 33N 05E 31 5E E Enockson - 01/30/1934 218 RG DO - -

81837 23635 41.284231 88.698578 099 33N 05E 31 6B D Zimmerman R Scherf 09/04/1984 35 RG DO - -

81838 - - - 099 33N 05E 32 8C R May Will DuPage Drilling 12/29/1976 295 RG IC - -

- 26862 41.286133 88.669886 - 33N 05E 32 - Lucie Farm Becker Oil Co. - 108 - - - -

81767 676 41.28976 88.665203 099 33N 05E 33 - J Wylie CE Woodruff 1942 245 RG DO - -

81768 675 41.28976 88.665203 099 33N 05E 33 - J Wylie CE Woodruff 1941 245 RG DO - -

258126 24817 41.282749 88.648154 099 33N 05E 33 1A Jeff Gallick Fordonski 03/26/1994 240 RG DO DL UN 239441 - - - 099 33N 05E 33 1A Allen Clark Knierim 02/16/1992 210 RG DO - BR 264241 - - - 099 33N 05E 33 1A Alan Leyes K&K Drilling/Brown 09/29/1993 210 RG DO DL UN 300254 25702 41.282694 88.652929 099 33N 05E 33 3A Bonnie & Ray Linder Calvin Bisping 10/27/1997 215 RG DO DL UN 258361 - - - 099 33N 05E 33 3B Gary Erickson K&K Drilling/Brown 11/30/1993 210 RG DO - UN 386631 - - - 099 33N 05E 33 3B Gary Eulkvon K&K Drilling/Brown 11/30/1993 210 RG DO - UN 274845 24818 41.289809 88.660413 099 33N 05E 33 4A Donald Sticha Lockport Well & Pump 07/31/1995 425 RG DO DL BR 285635 25330 41.28267 88.655317 099 33N 05E 33 4A Bruce Rodomski RIX 02/29/1996 217 RG DO DL UN 372997 27502 41.282659 88.655293 099 33N 05E 33 4A Theodore Bartelmey Tri County Well & Pump/Steve 08/05/2005 440 RG DO DL BR 286513 25218 41.286264 88.65547 099 33N 05E 33 4C Pete Smith RIX 03/25/1994 220 RG DO DL UN 259503 24853 41.284414 88.660172 099 33N 05E 33 6B Ron Berryman K&K Drilling/Brown 08/25/1994 206 RG DO DL UN 237052 24606 41.286212 88.660252 099 33N 05E 33 6C Mike Galloway Lot 2685 Fordonski 04/14/1992 210 RG DO - UN 237127 24776 41.286291 88.653078 099 33N 05E 33 6E Thomas & Mary Lanfear Lot 2695 Fordonski 01/18/1993 210 RG DO - UN 258122 - - - 099 33N 05E 33 6E John Logan Fordonski 12/06/1993 215 RG DO DL UN 362806 27226 41.286163 88.665035 099 33N 05E 33 8C Don Podgorny Area Well & Pump/Robert 04/20/2004 215 RG DO DL UN 260968 24917 41.287961 88.665119 099 33N 05E 33 8D Ray Eich Fordonski 08/08/1993 270 RG DO DL UN

- 24605 41.286212 88.660252 - 33N 05E 33 - Time Sadness Fordonski 06/23/1992 215 - - - -

- 25080 41.28358 88.654161 - 33N 05E 33 - Donald Sticha Fordonski 07/31/1995 425 - - - -

- 675 41.28973 88.665203 - 33N 05E 33 - Wylie John-Estate - 01/01/1941 245 - - - -

- 676 41.28976 88.665203 - 33N 05E 33 - Wylie John-Estate - 01/01/1942 245 - - - -

81769 - - - 099 33N 05E 34 - - - 02/02/1934 - RG DO - -

81770 - - - 099 33N 05E 34 - JJ Farrell CR Johnson 1945 60 RG DO - -

360335 27172 41.282969 88.628842 099 33N 05E 34 1A J Connell Group K&K Drilling/Jeff Hieser 04/16/2004 210 RG DO DL UN 365541 27327 41.282969 88.628842 099 33N 05E 34 1A J Connell Group K&K Drilling/Jeff Hieser 10/21/2004 215 RG DO DL UN 367263 27374 41.282957 88.628821 099 33N 05E 34 1A J Connell Group Contruction K&K Drilling/Jeff Hieser 01/10/2005 214 RG DO DL BR 288703 25389 41.282969 88.628842 099 33N 05E 34 1A D&S Construction K&K Drilling/Brown 04/25/1996 191 RG DO DL UN 288705 25390 41.282969 88.628842 099 33n 05E 34 1A Tom Small K&K Drilling/Brown 05/14/1996 215 RG DO DL BR 308133 25940 41.284776 88.628925 099 33N 05E 34 1B Richard Dazzo K&K Drilling/Knierim 02/03/1999 205 RG DO DL BR 81839 23636 41.284158 88.628143 099 33N 05E 34 1B N Higby P Knierim 06/09/1979 210 RG DO - -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 12 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Well Identification Coordinates Location Information Well Details Well ID ISGS Well ID Latitude Longitude FIPS TWN RNG SEC PLOT Owner Driller Drill Date Depth Record Type Use Well Type AQ Type 252426 - - - 099 33N 05E 34 1C Gary Hamilton K&K Drilling/Brown 07/22/1993 210 RG DO - BR 237154 24467 41.293787 88.631728 099 33N 05E 34 1D Gary Lurz Lot 2791 Knierim 07/10/1991 210 RG DO - UN 258498 24681 41.288395 88.629084 099 33N 05E 34 1D Walter Dudley Knierim 08/29/1991 208 RG DO - UN 268807 25033 41.293824 88.629322 099 33N 05E 34 1G Jerry Kubinski K&K Drilling/Brown 06/21/1995 208 RG DO DL UN 356900 27035 41.295634 88.629401 099 33N 05E 34 1H Mark Kellogg Area Well & Pump/Robert 11/01/2003 47 RG DO DL UN 367908 27385 41.284738 88.631314 099 33N 05E 34 2B Lisa Ording Area Well & Pump/Robert 10/25/2004 200 RG DO DL UN 364962 27286 41.286556 88.631414 099 33N 05E 34 2C Mike Dooley #1 K&K Drilling/Ken Knierim 09/03/2004 193 RG DO DL UN 280608 - - - 099 33N 05E 34 2F Heritage Lake Estates K&K Drilling/Brown 11/27/1995 207 RG DO DL UN 237062 24607 41.293787 88.631728 099 33N 05E 34 2G Jeff & Deanna Berg Lot 2793 Knierim 07/14/1992 214 RG DO - BR 265576 24967 - - 099 33N 05E 34 2G Jerry Kubinski K&K Drilling/Brown 11/11/1994 210 RG DO DL BR 268809 25034 41.295593 88.631808 099 33N 05E 34 2H Tom Small K&K Drilling/Brown 06/22/1995 213 RG DO DL UN 81840 - - - 099 33N 05E 34 3C T Safrawski C Johnson 06/28/1976 63 RG DO - -

375780 27581 41.295544 88.63419 099 33N 05E 34 3H Zack Malak #1 Area Well & Pump/Robert 10/10/2005 35 RG DO DL UN 275806 25081 41.295556 88.634214 099 33N 05E 34 3H Mike Mason #1 RIX 08/20/1995 240 RG DO DL BR 258320 - - - 099 33N 05E 34 5H Dave Odell Fordonski 11/06/1993 130 RG DO DL UN

- 25161 41.29198 88.631652 - 33N 05E 34 - Heritage Lake Estates Brown, Darwin 11/27/1995 207 - - - -

- 24941 41.295634 88.629401 - 33N 05E 34 - Hetelle, David Fordonski 09/22/1994 50 - - - -

- 27642 41.288419 88.626649 - 33N 05E 34 - Michelle Altman Area Well & Pump/Robert 02/08/2006 153 - - - -

- 22541 41.20939 88.633234 - 33N 05E 34 - Emmet, Moran - 12/01/1974 545 - - - -

- 24950 41.283039 88.624016 - 33N 05E 35 - Jim Kolanowski Fordonski 09/07/1994 420 - - - -

- 26227 41.286621 88.626591 - 33N 05E 35 - Erickson, Carl RIX 08/18/2000 192 - - - -

- 23608 41.28843 88.62667 - 33N 05E 35 - Lamping, Clarence Rob, Peter 06/17/1983 159 - - - -

- 677 41.293862 88.626912 - 33N 05E 35 - Schroeder - - 564 - - - -

- 26790 41.295672 88.626991 - 33N 05E 35 - Steve Spangler Strange, Michael 10/11/2002 43 - - - -

- 26377 41.295672 88.626991 - 33N 05E 35 - Matrtin Spicer Strange, Michael 04/15/2001 33 - - - -

- 22710 41.286621 88.626591 - 33N 05E 35 - Vicich Louis Stoneberger, Donald 10/01/1976 183 - - - -

- 26259 41.208916 88.595456 - 32N 05E 36 - Johnson, Howard RIX, John Richard 09/20/2000 75 - - - -

- 24674 41.282403 88.705632 - 33N 05E 36 - Donovan, Art Fordonski 06/20/1992 435 - - - -

- 25401 41.282403 88.705632 - 33N 05E 36 - Housing Authority - LaSalle Co Brown, Darwin 07/12/1996 440 - - - -

- 23619 41.284231 88.705655 - 33N 05E 36 - Rieuf, Clarence Rob, Ronald Gene 06/16/1981 - - - - -

- 23620 41.282403 88.705632 - 33N 05E 36 - Tri County Well and Pump, Inc Fykes, Charles N 09/30/1978 445 - - - -

- 25079 41.282403 88.705632 - 33N 05E 36 - RIX Vidito, Anna 08/06/1995 480 - - - -

09990060 5686 - - 099 33N 05E 16 6F Whispering Pines MHP - 1974 460 I - - -

09934335 11946 - - 099 33N 05E 20 4C Royster-Clark, Inc - - - I - - -

09934335 11945 - - 099 33N 05E 20 4E Royster-Clark, Inc - - 360 I - - -

09934330 - - - 099 33N 05E 21 - PCS Phosphate-Marseilles Oprtn - - 140 I - - -

09934330 11944 - - 099 33N 05E 21 4C PCS Phosphate-Marseilles Oprtn - - - U - - -

09934330 11943 - - 099 33N 05E 21 5C PCS Phosphate-Marseilles Oprtn - - 440 I - - -

09914770 11927 - - 099 33N 05E 21 7A Exelon-LaSalle Co Station - - - I - - -

09991050 5776 - - 099 33N 05E 23 1G Seneca Albrecht Well Drilling 1993 1445 I - D -

09991050 2811 - - 099 33N 05E 24 8C Seneca J Otis Heflin 1927 700 I - D -

09991050 2810 - - 099 33N 05E 24 8C Seneca JP Miller Art Well 1943 704 I - C -

CRA 45136 (16) LaSalle Generating Station

TABLE A-1 Page 13 of 13 WATER WELL INVENTORY DATABASE SEARCH PUBLIC, INDUSTRIAL, COMMERCIAL ILLINOIS STATE WATER SURVEY AND ILLINOIS STATE GEOLOGICAL SURVEY JUNE 2006 Abbreviations/Definitions Well ID Illinois State Water Survey Identification Number FIPS County Code Number TWN Civil Township RNG Range SEC Section PLOT 10-Acre plot location within the Section ISGS Well ID Illinois State Geological Survey Identification Number Depth Depth of Well to the Nearest Foot Drill Date Date Well Initially Drilled/Installed Record Type: Use: Aquifer Type:

R - Construction Report CO - Conservation BR - Bedrock G - Geology CS - Community Supply DH - Dry Hole S - Sealed DO - Domestic SW - Surface Water A - Affidavit DW - Dewatering UN - Unconsolidated C - Chemical Analysis IC - Industrial/Commercial - - Unknown I - Inventory IN - Injection Well X - Comments in Owners Field Something Unusual IR - Irrigation O - Any other type of record MO - Monitoring P - Pump installation NC - Non-Community NW - Non-Well Source OB - Observation Well Type: PK - Park Blank - Assumed Drilled RC - Recovery Well BD - Bored RW - Relief Well DL - Drilled SC - School DU - Dug (phased out) ST - State DR - Driven TB - Test Boring NW - Non-Well TH - Test Hole SP - Sandpoint TW - Test Well SG - Spring - - Unknown

- - Assumed Drilled or Possibly Unknown 45136 (16) LaSalle Generating Station

Revision 0 APPENDIX B MONITORING WELL STRATIGRAPHIC AND INSTRUMENTATION LOGS 045136 (16) LaSalle Generating Station

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-101S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 9, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

GROUND SURFACE 705.90 TOP OF CASING 705.52 Soils removed by "soft dig", no stratigraphy Concrete defined. Silty Clay at approximately 1.0ft BGS 2 Bentonite Chips 2" O

/ PVC 4 Well Casing 9" O

/ Borehole 6

699.10 CL SILTY CLAY - trace fine subangular 100 0.0 8 gravels, stiff, low plasticity, competent, gray, dry to moist Sand Pack 10 2" O

/ PVC Well Screen 12 100 0.0 14 690.90 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

700.90 to 690.90ft AMSL 5.00 to 15.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

702.90 to 690.90ft AMSL 3.00 to 15.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-102S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 10, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: N. KUHL ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

GROUND SURFACE 707.54 TOP OF CASING 706.96 FILL - asphalt, compacted fill, dry Concrete 2 705.54 Soils removed by "soft dig", no stratigraphy defined. Silty Clay at approximately 1.0ft BGS 2" O

/ PVC 4 703.54 Well Casing CL CLAY - trace gravel, medium to soft, low plasticity, brown/gray, mottled, dry 7 0.0 Bentonite 6 Chips 9" O

/ Borehole 6 0.0

- soft at 7.5ft BGS 8 699.54 CL CLAY-trace gravel, firm, medium plasticity, gray, wet 11 0.0 10

- soft from 9.5 to 9.8 ft BGS 13 0.0 12 19 0.0 14 Sand Pack 692.54 2" O

/ PVC 28 0.0 CL CLAY-trace gravel, firm, medium plasticity, Well Screen 16 brown, dry 691.04

- <1/8" sand seam at 15.0 ft BGS 23 0.0

- soft at 16.0 ft BGS 18 CL CLAY-trace gravel, soft, low plasticity, gray, moist 22 0.0 20 15 0.0 22 12 0.0 24

- sand seam, fine grained 1/4-1/8" thick, gray Bentonite 11 0.0 at 25.0ft BGS Chips 26 10 0.0 28 10 0.0 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 677.54 END OF BOREHOLE @ 30.0ft BGS WELL DETAILS Screened interval:

32 697.54 to 687.54ft AMSL 10.00 to 20.00ft BGS Length: 10ft 34 Diameter: 2in Slot Size: 0.010 Sand Pack:

36 699.54 to 687.04ft AMSL 8.00 to 20.50ft BGS Material: #5 Sand 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 2 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-103S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 10, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

GROUND SURFACE 709.26 TOP OF CASING 708.91 Soils removed by "soft dig", no stratigraphy Concrete defined. Silty Clay at approximately 1.5ft BGS Bentonite 2 Chips 2" O

/ PVC 4 Well Casing 704.26 CL SILTY CLAY - high silt content, trace fine 9" O

/ Borehole 6 subangular gravels, stiff, low to medium plasticity, brown/gray, dry to moist

- olive/gray, mottle at 7.0ft BGS 100 0.0 8

Sand Pack 10 2" O

/ PVC

- brown, increase in gravel content at 10.5ft Well Screen BGS 12 - some medium sands, trace plasticity at 12.0ft BGS 100 0.0 14

- decrease in brown, more gray at 15.0ft BGS 16 100 0.0 18

- trace medium gravel, subangular to angular at 18.5ft BGS 20 - sample stuck in geoprobe line, no recovery for 5 ft at 20.0ft BGS 22 0 0.0 24 684.26 CL SILTY CLAY - high silt content, medium 26 plasticity, gray, moist 100 0.0 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 100 0.0 Bentonite Chips 34 36 100 0.0 38 - decrease in plasticity at 38.0ft BGS NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 2 of 2 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-103S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 10, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

42 100 0.0

- medium to high plasticity, trace fine gravels, angular at 43.0ft BGS 44 46 100 0.0 48 50 659.26 END OF BOREHOLE @ 50.0ft BGS WELL DETAILS Screened interval:

52 704.26 to 694.26ft AMSL 5.00 to 15.00ft BGS Length: 10ft 54 Diameter: 2in Slot Size: 0.010 Sand Pack:

56 706.26 to 694.26ft AMSL 3.00 to 15.00ft BGS Material: #5 Sand 58 60 62 64 66 68 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 70 72 74 76 78 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-104S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 11, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 712.16 GROUND SURFACE 708.61 SW-GW SANDS AND GRAVELS - fine to Concrete coarse grained, fine to medium gravel, well graded, compact, brown/gray, moist Bentonite 2 Chips 2" O

/ PVC Well Casing 4 - wet at 4.0ft BGS 9" O

/ Borehole 6

Sand Pack 8 2" O

/ PVC Well Screen 10 698.61 CL SILTY CLAY - trace fine and medium gravel, stiff, low plasticity, dark gray, dry to moist 12 0.0 14 Natural Collapse 693.61 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

705.61 to 695.61ft AMSL 3.00 to 13.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

706.61 to 695.61ft AMSL 2.00 to 13.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-105S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 11, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 712.41 GROUND SURFACE 708.96 SW-GW (FILL) SANDS AND GRAVELS - fine Concrete to coarse grained, fine to medium gravel, trace cobbles, well graded, dense, Bentonite 2 brown/gray, dry to moist Chips 2" O

/ PVC Well Casing 4

- wet at 4.5ft BGS 9" O

/ Borehole 6

Sand Pack 8 2" O

/ PVC Well Screen 10 698.96 CL SILTY CLAY - trace fine subangular gravel, trace fine sands, stiff, low plasticity, dark gray, dry to moist 12 0.0 14 Natural Collapse 693.96 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

705.96 to 695.96ft AMSL 3.00 to 13.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

706.96 to 695.96ft AMSL 2.00 to 13.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-106S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 10, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: N. KUHL ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 711.41 GROUND SURFACE 708.58 FILL - fill material, gravelly sand, damp Bentonite 2 Grout 2" O

/ PVC Well Casing 4 704.58 13 0.0 CL CLAY - trace gravel, firm, medium plasticity, brown/gray, mottled, wet 9" O

/ Borehole 6

Sand Pack

- soft at 7.0ft BGS 5 0.0 8 2" O

/ PVC Well Screen 19 0.0

- <1/8" sand seam at 9.6ft BGS 10

- <1/8" sand seam at 10.5ft BGS 14 0.0 697.08 12 CL CLAY-medium to firm, high plasticity, dark gray 8 0.0 14 14 0.0 693.58 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

706.58 to 696.58ft AMSL 2.00 to 12.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

707.08 to 693.58ft AMSL 1.50 to 15.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-107S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 11, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: N. KUHL ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

GROUND SURFACE 709.27 TOP OF CASING 708.72 Soils removed by "soft dig", no stratigraphy defined. Sand, Gravel and Cobble Fill to Bentonite approximately 6.0 ft BGS. Silty Clay at Grout 2 approximately 6.0 ft BGS 2" O

/ PVC Well Casing 4

9" O

/ Borehole 6

702.27 CL CLAY - trace gravel, sand seams, soft, 8 medium plasticity, gray, moist Sand Pack 7 0.0 2" O

/ PVC

- <1/4" gravel seam at 9.5ft BGS Well Screen 10 7 0.0 12 12 0.0 14 12 0.0 694.27 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

705.27 to 695.27ft AMSL 4.00 to 14.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

707.27 to 694.27ft AMSL 2.00 to 15.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-108S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 10, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 714.02 GROUND SURFACE 711.17 Soils removed by "soft dig", no stratigraphy Concrete defined. Silty Clay at approximately 0.4 ft BGS Bentonite 2 Chips 2" O

/ PVC Well Casing

- gravel seam, saturated at 3.5ft BGS 4

9" O

/ Borehole 6

Sand Pack 8 2" O

/ PVC 702.67 Well Screen CL SILTY CLAY - trace fine and medium 100 0.0 gravel, subangular, stiff, low plasticity, gray, 10 dry to moist 701.17 CL SILTY CLAY - high silt content, trace fine gravels, medium to high plasticity 12 100 0.0 14 Natural Collapse 696.17 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

708.17 to 698.17ft AMSL 3.00 to 13.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

709.17 to 698.17ft AMSL 2.00 to 13.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-109S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 11, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

GROUND SURFACE 711.64 TOP OF CASING 711.27 SW-GW (FILL) SANDS AND GRAVELS - fine Concrete to coarse grained, fine to medium gravel, Bentonite subangular to subrounded, well graded, Chips 2 dense, brown 2" O

/ PVC

- wet at 3.0ft BGS Well Casing 4

9" O

/ Borehole 6

Sand Pack 8 2" O

/ PVC Well Screen 701.94 10 CL SILTY CLAY - some fine gravel, angular to subangular, competent, stiff, low plasticity, gray, dry to moist 12 100 0.0 14 Natural Collapse 696.64 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

708.64 to 698.64ft AMSL 3.00 to 13.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

709.64 to 698.64ft AMSL 2.00 to 13.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-110S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 4, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 505.85 GROUND SURFACE 502.35 Soils removed by "soft dig", no stratigraphy Concrete defined. Silty Clay at approximately 1.5ft BGS Bentonite Chips 2 2" O

/ PVC

- 2" sandstone layer, refusal, continue with Well Casing 4-1/4" HSA at 4.0 ft BGS 100 0.0 4 498.35 Sand Pack SILTY CLAY 2" O

/ PVC Well Screen 6

- SANDSTONE (BEDROCK), very granular, 495.85 9" O

/ Borehole redish tint, refusal at 6.5ft BGS WELL DETAILS 8 END OF BOREHOLE @ 6.5ft BGS Screened interval:

500.85 to 495.85ft AMSL 1.50 to 6.50ft BGS 10 Length: 5ft Diameter: 2in Slot Size: 0.010 12 Sand Pack:

501.35 to 495.85ft AMSL 1.00 to 6.50ft BGS 14 Material: #5 Sand 16 18 20 22 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-111S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 12, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: N. KUHL ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

GROUND SURFACE 706.04 TOP OF CASING 705.41 Soils removed by "soft dig", no stratigraphy Concrete defined. Clay at approximately 2 ft BGS 2 Bentonite 2" O

/ PVC 4 Well Casing 9" O

/ Borehole 6 700.04 CLAY, low plasticity, trace gravels, medium to firm, gray 11 0 8

Sand Pack 2" O

/ PVC 9 0 Well Screen 10

- possible sand seam at 11.0ft BGS 11 0 12 12 0 14 692.04 END OF BOREHOLE @ 14.0ft BGS WELL DETAILS Screened interval:

16 702.04 to 692.04ft AMSL 4.00 to 14.00ft BGS Length: 10ft 18 Diameter: 2in Slot Size: 0.010 Sand Pack:

20 703.04 to 692.04ft AMSL 3.00 to 14.00ft BGS Material: #5 Sand 22 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-112S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 12, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 718.67 GROUND SURFACE 715.65 Soils removed by "soft dig" Concrete 2 Bentonite Chips 2" O

/ PVC 4 Well Casing

- silty clay at approximately 5ft BGS 9" O

/ Borehole 6

708.65 CL SILTY CLAY - high slit content, trace fine 8 subangular gravel, stiff, low plasticity, gray, dry to moist Sand Pack 2" O

/ PVC Well Screen 10 12 60 0.0 14 Natural 700.65 Collapse END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

711.65 to 701.65ft AMSL 4.00 to 14.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

712.65 to 701.65ft AMSL 3.00 to 14.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

STRATIGRAPHIC AND INSTRUMENTATION LOG (OVERBURDEN) Page 1 of 1 PROJECT NAME: LASALLE GENERATING STATION HOLE DESIGNATION: MW-LS-113S PROJECT NUMBER: 45136-24 DATE COMPLETED: May 15, 2006 CLIENT: EXELON GENERATION COMPANY LLC DRILLING METHOD: 4-1/4" HSA/DIRECT PUSH LOCATION: MARSEILLES, ILLINOIS FIELD PERSONNEL: B. WILLIAMS ELEV. SAMPLE DEPTH STRATIGRAPHIC DESCRIPTION & REMARKS ft Monitoring Well ft BGS NUMBER INTERVAL 'N' VALUE PID (PPM)

AMSL REC (%)

TOP OF RISER 714.21 GROUND SURFACE 711.23 Soils removed by "soft dig", stratigraphy not Concrete defined 2 Bentonite Chips 2" O

/ PVC 4 Well Casing

- silty clay at approximately 5ft BGS 9" O

/ Borehole 6 705.23 CL SILTY CLAY - high slit content, trace fine subangular gravel, trace vegetation, stiff, low plasticity, brown/gray, dry to moist 40 0.0 8

Sand Pack 2" O

/ PVC Well Screen 10 12 50 0.0 14 696.23 END OF BOREHOLE @ 15.0ft BGS WELL DETAILS 16 Screened interval:

707.23 to 697.23ft AMSL 4.00 to 14.00ft BGS 18 Length: 10ft Diameter: 2in Slot Size: 0.010 20 Sand Pack:

708.23 to 697.23ft AMSL 3.00 to 14.00ft BGS 22 Material: #5 Sand 24 26 28 OVERBURDEN LOG 45136-24.GPJ CRA_CORP.GDT 6/6/06 30 32 34 36 38 NOTES: MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE

Revision 0 APPENDIX C QUALITY ASSURANCE PROGRAM -

TELEDYNE BROWN ENGINEERING, INC.

045136 (16) LaSalle Generating Station

TABLE OF CONTENTS Section Title Page 1.0 KNOXVILLE QAM SECTION INTRODUCTION 7 2.0 QUALITY SYSTEM 10 2.1 Policy 10 2.2 Quality System Structure 10 2.3 Quality System Objectives 10 2.4 Personnel Orientation, Training, and Qualification 11 3.0 ORGANIZATION, AUTHORITY, AND RESPONSIBILITY 12 4.0 PERSONNEL ORIENTATION, DATA INTEGRITY, TRAINING, AND QUALIFICATION 13 4.1 Orientation 13 4.2 Data Integrity 13 4.3 Training 13 4.4 Qualification 13 4.5 Records 13 5.0 CUSTOMER INTERFACES 14 5.1 Interface Personnel 14 5.2 Bid Requests and Tenders 14 5.3 Contracts 14 5.4 TBEs Expectation of Customers 14 5.5 Customer Satisfaction 15 5.5.1 Customer Complaints 15 5.5.2 Customer Confidentiality 15 6.0 DOCUMENTATION GENERATION AND CONTROL 16 6.1 General 16 6.2 New Documentation 16 6.3 Documentation Changes 16 Page 2 of 32

TABLE OF CONTENTS - Continued 6.4 Documentation Lists and Distributions 16 6.5 Other Documentation 16 6.6 Documentation Reviews 16 7.0 DESIGN OF LABORATORY CONTROLS 17 7.1 General 17 7.2 Facility 17 7.3 Technical Processes and Methods 17 7.3.1 Operational Flow 17 7.3.2 Methods 18 7.3.3 Data Reduction and Analysis 18 7.4 Verification of Technical Processes, Methods, and Software 18 7.4.1 Operational Flow Verification 18 7.4.2 Method Verifications 18 7.4.3 Data Reduction and Analysis Verification 18 7.5 Design of Quality Controls 18 7.5.1 General 19 7.5.2 Demonstration of Capability (D of C) 19 7.5.3 Process Control Checks 19 7.6 Counting Instrument Controls 20 8.0 PURCHASING AND SUBCONTRACT CONTROLS 21 8.1 General 21 8.2 Source Selection 21 8.3 Procurement of Supplies and Support Services 21 8.3.1 Catalog Supplies 21 8.3.2 Support Services 21 8.3.3 Equipment and Software 22 8.4 Subcontracting of Analytical Services 22 8.5 Acceptance of Items or Services 22 Page 3 of 32

TABLE OF CONTENTS - Continued 9.0 TEST SAMPLE IDENTIFICATION AND CONTROL 23 9.1 Sample Identification 23 9.2 LIMS 23 9.3 Sample Control 23 10.0 SPECIAL PROCESSES, INSPECTION, AND TEST 24 10.1 Special Processes 24 10.2 Inspections and Tests 24 10.2.1 Intra Laboratory Checks (QC Checks) 24 10.2.2 Inter Laboratory Checks 24 10.2.3 Data Reviews 24 10.3 Control of Sampling of Samples 24 10.4 Reference Standards / Material 24 10.4.1 Weights and Temperatures 25 10.4.2 Radioactive Materials 25 11.0 EQUIPMENT MAINTENANCE AND CALIBRATION 26 11.1 General 26 11.2 Support Equipment 26 11.3 Instruments 26 11.4 Nonconformances and Corrective Actions 26 11.5 Records 27 12.0 NONCONFORMANCE CONTROLS 28 12.1 General 28 12.2 Responsibility and Authority 28 12.3 10CFR21 Reporting 28 Page 4 of 32

TABLE OF CONTENTS - Continued 13.0 CORRECTIVE AND PREVENTIVE ACTIONS 29 13.1 General 29 13.2 Corrective Actions 29 13.3 Preventive Actions 29 14.0 RESULTS ANALYSIS AND REPORTING 30 14.1 General 30 14.2 Results Review 30 14.3 Reports 30 15.0 RECORDS 31 15.1 General 31 15.2 Type of Records 31 15.3 Storage and Retention 31 15.4 Destruction or Disposal 31 16.0 ASSESSMENTS 32 16.1 General 32 16.2 Audits 32 16.3 Management Reviews 32 Page 5 of 32

REVISION HISTORY Revision 7 Complete re-write January 1, 2005 Bill Meyer Revision 8 Updated organization chart, minor change to 1.0, 4.4, 7.5.3.2, 10.2.3, and 12.3 Page 6 of 32

1.0 Knoxville QAM Section Introduction This Quality Assurance Manual (QAM) and related Procedures describes the Knoxville Environmental Services Laboratorys QA system. This system is designed to meet multiple quality standards imposed by Customers and regulatory agencies including:

NRCs 10 CFR 50 Appendix B NRCs Regulatory Guide 4.15 DOEs Order 414.1 DOEs QSAS ANSI N 42.23 ANSI N 13.30 NELAC Standard, Chapter 5 The Environmental Services (ES) Laboratory does low level radioactivity analyses for Power Plants and other customers. It primarily analyzes environmental samples (natural products from around plants such as milk), in-plant samples (air filters, waters), bioassay samples from customers employees, and waste disposal samples (liquids and solids).

Potable and non-potable water samples are tested using methods based on EPA standards as cited in State licenses (see Procedure 4010). The listing [current as of initial printing of this Manual - see current index for revision status and additions / deletions] of implementing Procedures (SOPs) covering Administration, Methods, Counting Instruments, Technical, Miscellaneous, and LIMS is shown in Table 1-1. Reference to these Procedures by number is made throughout this QAM.

Table 1-1 Number Title Part 1 Administrative Procedures Validation and Verification of Computer Programs for Radiochemistry Data 1001 Reduction 1002 Organization and Responsibility 1003 Control, Retention, and Disposal of Quality Assurance Records 1004 Definitions 1005 Data Integrity 1006 Job Descriptions 1007 Training and Certifications 1008 Procedure and Document Control 1009 Calibration System 1010 Nonconformance Controls 1011 10CFR21 Reporting 1012 Corrective Action and Preventive Action Page 7 of 32

Number Title 1013 Internal Audits and Management Reviews 1014 RFP, Contract Review, and Order Entry (formerly 4001) 1015 Procurement Controls Part 2 Method Procedures 2001 Alpha Isotopic and Plutonium-241 2002 Carbon-14 Activity in Various Matrices Carbon-14 and Tritium in Soils, Solids, and Biological Samples; Harvey 2003 Oxidizer Method 2004 Cerium-141 and Cerium-144 by Radiochemical Separation 2005 Cesium-137 by Radiochemical Separation 2006 Iron-55 Activity in Various Matrices 2007 Gamma Emitting Radioisotope Analysis 2008 Gross Alpha and/or Gross Beta Activity in Various Matrices 2009 Gross Beta Minus Potassium-40 Activity in Urine and Fecal Samples 2010 Tritium and Carbon-14 Analysis by Liquid Scintillation 2011 Tritium Analysis in Drinking Water by Liquid Scintillation 2012 Radioiodine in Various Matrices 2013 Radionickel Activity in Various Matrices 2014 Phosphorus-32 Activity in Various Matrices 2015 Lead-210 Activity in Various Matrices 2016 Radium-226 Analysis in Various Matrices 2017 Total Radium in Water Samples 2018 Radiostrontium Analysis by Chemical Separation 2019 Radiostrontium Analysis by Ion Exchange 2020 Sulfur-35 Analysis 2021 Technetium-99 Analysis by Eichrom Resin Separation 2022 Total Uranium Analysis by KPA 2023 Compositing of Samples 2024 Dry Ashing of Environmental Samples 2025 Preparation and Standardization of Carrier Solutions 2026 Radioactive Reference Standard Solutions and Records 2027 Glassware Washing and Storage 2028 Moisture Content of Various Matrices 2029 Polonium-210 Activity in Various Matrices 2030 Promethium-147 Analysis Page 8 of 32

Number Title Part 3 Instrument Procedures 3001 Calibration and Control of Gamma-Ray Spectrometers 3002 Calibration of Alpha Spectrometers 3003 Calibration and Control of Alpha and Beta Counting Instruments 3004 Calibration and Control of Liquid Scintillation Counters 3005 Calibration and Operation of pH Meters 3006 Balance Calibration and Check 3008 Negative Results Evaluation Policy 3009 Use and Maintenance of Mechanical Pipettors 3010 Microwave Digestion System Use and Maintenance Part 4 Technical Procedures 4001 Not Used 4002 QC Checks on Data 4003 Sample Regent and Control 4004 Data Package Preparation and Reporting 4005 Blank, Spike, and Duplicate Controls 4006 Inter-Laboratory Comparison Study Process 4007 Method Basis and Initial Validation Process 4008 Not Used 4009 MDL Controls 4010 State Certification Process 4011 Accuracy, Precision, Efficiency, and Bias Controls and Data Quality Objectives 4012 Not Used 4013 Not Used 4014 Facility Operation and Control 4015 Documentation of Analytical Laboratory Logbooks (formerly 1002) 4016 Total Propagated Uncertainty (formerly 1004) 4017 LIMS Operation 4018 Instrument Calibration System 4019 Radioactive Reference Material Standards Part 5 Miscellaneous Procedures 5001 Laboratory Hood Operations 5002 Operation and Maintenance of Deionized Water System 5003 Waste Management 5004 Acid Neutralization and Purification System Operation Procedure Page 9 of 32

Part 6 LIMS 6001 LIMS Raw Data Processing and Reporting 6002 Software Development and/or Pilots of COTS Packages 6003 Software Change and Version Control 6004 Backup of Data and System Files 6005 Disaster Recovery Plan 6006 LIMS Hardware 6007 LIMS User Access 6008 LIMS Training 6009 LIMS Security 2.0 QUALITY SYSTEM The TBE-ES QA system is designed to comply with multiple customer- and regulatory agency-imposed specifications related to quality. This quality system applies to all activities of TBE-ES that affect the quality of analyses performed by the laboratory.

2.1 Policy The TBE quality policy, given in Company Policy P-501, is TBE will continually improve our processes and effectiveness in providing products and services that exceed our customers expectations.

This policy is amplified by this Laboratorys commitment, as attested to by the title page signatures, to perform all work to good professional practices and to deliver high quality services to our customers with full data integrity. (See Section 4.0 and Procedure 1005).

2.2 Quality System Structure The Quality System is operated by the organizations described in Section 3.0 of this Manual. The Quality System is described in this Manual and in the Procedures Manual, both of which are maintained by the QA Manager. Procedures are divided into 6 sections - Administrative, Methods, Equipments, Technical, Miscellaneous, and LIMS. This Manual is structured as shown in the Table of Contents and refers to Procedures when applicable. Cross references to the various imposed quality specifications are contained in Appendices to this Manual.

2.3 Quality System Objectives The Quality System is established to meet the objective of assuring all operations are planned and executed in accordance with system requirements. The Quality System also assures that performance evaluations are performed (see Procedure 4006), and that appropriate verifications are performed (see Procedures in the 1000 and 4000 series) to further assure compliance. Verification includes Page 10 of 32

examination of final reports (prior to submittal to customers) to determine their quality (see Procedure 4004).

To further these objectives, various in-process assessments of data, as well as assessments of the system, via internal audits and management reviews, are performed. Both internal experts and customer / regulatory agencies perform further assessments of the system and compliance to requirements.

2.4 Personnel Orientation, Training, and Qualification TBE provides indoctrination and training to employees and performs proficiency evaluation of technical personnel. This effort is described in Section 4.0.

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3.0 ORGANIZATION, AUTHORITY, AND RESPONSIBILITY TBE has established an effective organization for conducting laboratory analyses at the Knoxville Environmental Services Laboratory. The basic organization is shown in Figure 3-1. Detail organization charts with names, authorities, and responsibilities are given in Procedure 1002. Job descriptions are given in Procedure 1006.

This organization provides clearly established Quality Assurance authorities, duties, and functions. QA has the organizational freedom needed to:

(1) Identify problems (2) Stop nonconforming work (3) Initiate investigations (4) Recommend corrective and preventive actions (5) Provide solutions or recommend solutions (6) Verify implementation of actions All Laboratory personnel have the authority and resources to do their assigned duties and have the freedom to act on problems. The QA personnel have direct, independent access to Company management as shown in Figure 3-1.

President VP VP Administration & QA Environmental Product Assurance Director Lab QA Manager Lab Operations Manager Program Lab Administration Managers Supervisor Staff Figure 3.1. Laboratory Organization Page 12 of 32

4.0 PERSONNEL ORIENTATION, DATA INTEGRITY, TRAINING, AND QUALIFICATION 4.1 Orientation All laboratory personnel must receive orientation to the quality program if their work can affect quality. Orientation includes a brief review of customer- and regulatory agency-imposed quality requirements, the structure of the QAM, and the implementing procedures. The goal of orientation is to cover the nature and goals of the QA program.

4.2 Data Integrity The primary output of the Laboratory is data. Special emphasis and training in data integrity is given to all personnel whose work provides or supports data delivery. The Laboratory Data Integrity Procedure (Procedure 1005) describes training, personnel attestations, and monitoring operations. Annual reviews are required.

4.3 Training The Quality Assurance Manager (QAM) maintains a training matrix indicating which laboratory personnel need training in which specific Procedures. This matrix is updated when personnel change or change assignments. All personnel are trained per these requirements and procedures. This training program is described in Procedure 1007. The assigned responsibilities for employees are described in Procedure 1002 (See Section 3.0) on Organization and in Procedure 1006, Job Descriptions. Refresher training or re-training is given annually as appropriate.

4.4 Qualification Personnel are qualified as required by their job description. Management and non-analysts are evaluated based on past experience, education, and managements assessment of their capabilities. Formal qualification is required of analysts and related technical personnel who perform laboratory functions. Each applicable person is given training and then formally evaluated by the Operations Manager (or his designees) and by QA. Each analyst must initially demonstrate capability to perform each assigned analytical effort. Each year, thereafter, he or she must perform similar analyses on Interlab Comparison Samples (see Procedure 4006) or on equivalent blanks and spikes samples. Acceptable results extend qualifications (certification). Unacceptable results require retraining in the subject method / Procedures. (See Procedure 1007 for added information, records, forms, etc. used.)

4.5 Records Records of training subjects, contents, attendees, instructors, and certifications are maintained by QA.

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5.0 CUSTOMER INTERFACES 5.1 Interface Personnel The Laboratory has designated Program Managers as the primary interface with all customers. Other interfaces may be the QA Manager or the Lab Operations Manager.

5.2 Bid Requests and Tenders The Program Managers respond to customer requests for bids and proposals per Procedure 1014 for bids, proposals, and contract reviews. They clarify customer requests so both the customer and the lab staff understand requests. As responses are developed, internal reviews are conducted to ensure that requirements are adequately defined and documented and to verify that the Laboratory has adequate resources in physical capabilities, personal skills, and technical information to perform the work. Accreditation needs are reviewed. If subcontracts are required to perform any analysis, the subcontractor is similarly evaluated and the client notified in writing of the effort. Most qualifications are routine with standard pricing and the review of these quotes is performed by the Program Manager. Larger or more complex quotes are reviewed by the Operations Manager and the QA Manager (or designees). Evidence of review is by initialing and dating applicable papers, signatures on quotations, or by memo.

5.3 Contracts The Program Managers receive contract awards (oral or written) and generate the work planning for initiation preparation (charge numbers, data structure or contents in LIMS, etc.). They review contracts for possible differences from quotations and, if acceptable, contracts are processed. Documentation of the review is by initials and date as a minimum. Contract changes receive similar reviews and planning.

5.4 TBEs Expectation of Customers TBE expects customers to provide samples suitable for lab analysis. These expectations include:

Accurate and unambiguous identification of samples Proper collection and preservation of samples Use of appropriate containers free from external and internal contamination Integrity preservation during shipment and timely delivery of samples that are age sensitive Adequate sized samples that allow for retest, if needed Specification of unique MOA/MDC requirements Alerting the lab about abnormal samples (high activity, different chemical contents, etc.)

Chain of custody initiation, when required.

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5.5 Customer Satisfaction TBEs quality policy centers on customer satisfaction (See 2.0). TBE will work to satisfy customers through full compliance with contract requirements, providing accurate data and properly responding to any questions or complaints.

Customers are provided full cooperation in their monitoring of Laboratory performance. Customers are notified if any applicable State Accreditation is withdrawn, revoked, or suspended.

5.5.1 Customer Complaints Any customer complaints are documented and tracked to closure. Most complaints concern analysis data and are received by Program Managers. They log each such complaint, order retests for verification, and provide documented results to customers. Complaints may also be received by QA or Operations.

If complaints are other than re-test type, the nonconformance and corrective action systems (Sections 12 and 13) are used to resolve them and record all actions taken.

5.5.2 Customer Confidentiality All laboratory personnel maintain confidentiality of customer-unique information.

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6.0 DOCUMENTATION GENERATION & CONTROL 6.1 General The documentation generation and control system is detailed in Procedure 1008. An overview is given below. The basic quality system documents are described in Section 2.0.

6.2 New Documentation Each Procedure and this QAM is written by appropriate personnel, validated if applicable (see Section 7.0), reviewed for adequacy, completeness, and correctness, and, if acceptable, accepted by the authorized approver [QA Manager, Operations Manager (or their designee)]. Both approvals are required if a Procedure affects both QA and Operations. (See Responsibilities in Section 3.0). These procedures control the quality measurements and their accuracy.

Each document carries a unique identification number, a revision level, dates, page numbers and total page count, and approver identification and sign off. If TBE writes code for software, the software is version identified and issued after Verification and Validation per Section 7.0.

6.3 Documentation Changes Each change is reviewed in the same manner and by the same people as new documentation. Revision identifications are updated and changes indicated by side bars, italicized words, or by revision description when practical. Obsolete revisions are maintained by QA after being identified as obsolete.

6.4 Documentation Lists and Distributions Computer indexes of documents are maintained by Quality showing the current authorized revision level of each document. These revisions are placed on the Laboratory server and obsolete ones are removed so that all personnel have only the current documents. If hard copies are produced and distributed, separate distribution lists are maintained indicating who has them and their revision level(s).

Copies downloaded off the server are uncontrolled unless verified by the user (on the computer) to be the latest revision.

6.5 Other Documentation In addition to TBE-generated documentation, QA maintains copies of applicable specifications, regulations, and standard methods.

6.6 Documentation Reviews Each issued document is reviewed at least every third year by the approving personnel. This review determines continued suitability for use and compliance with requirements.

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7.0 DESIGN OF LABORATORY CONTROLS 7.1 General The Laboratory and its operating procedures are designed specifically for low level (environmental and in-plant) radioactive sample analysis. The various aspects of the laboratory design include the following which are discussed in subsequent paragraphs of this Section:

(a) Facility (b) Technical Processes and Methods (c) Verification of Design of Processes, Methods, and Software.

(d) Design of Quality Controls (e) Counting Instrument Controls 7.2 Facility The facility was designed and built in 2000 to facilitate correct performance of operations in accordance with good laboratory practices and regulatory requirements. It provides security for operations and samples. It separates sample storage areas based on activity levels, separates wet chemistry from counting instrumentation for contamination control, and provides space and electronic systems for documentation, analysis, and record storage. Procedure 4014 describes the facility, room uses, layouts, etc.

7.3 Technical Processes and Methods 7.3.1 Operational Flow The laboratory design provides for sample receipt and storage (including special environmental provisions for perishable items) where samples are received from clients and other labs (see Section 9.0). The samples are logged into the computer based Laboratory Information Management System (LIMS) and receive unique identification numbers and bar code labels. (See Procedure 4017 for LIMS description and user procedures). The Program Managers then plan the work and assure LIMS contains any special instructions to analysts. Samples then go to sample preparation, wet chemistry (for chemical separation), and counting based on the radionuclides. See Procedures in the 2000 and 3000 series. Analysts perform the required tasks with data being entered into logbooks, LIMS, and counting equipment data systems as appropriate. Results are collected and reviewed by the Operations Manager and Program Managers and reports to clients are generated (See Section 14.0). All records (electronic or hard copy) are maintained in files or in back-up electronic copies (see Section 15.0). After the required hold periods and client notification and approval, samples are disposed of in compliance with regulatory requirements (see Procedures 5003 and 5004).

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7.3.2 Methods The laboratory methods documented in the 2000 and 3000 series of Procedures were primarily developed by senior TBE laboratory personnel based on years of experience at our prior facility in New Jersey. They have been improved, supplemented and implemented here. Where EPA or other accepted national methods exist (primarily for water analyses under State certification programs - see Procedure 4010), the TBE methods conform to the imposed requirements or State accepted alternate requirements. Any method modifications are documented and described in the Procedure. There are no nationally recognized methods for most other analysis methods but references to other method documents are noted where applicable.

7.3.3 Data Reduction and Analysis Whenever possible automatic data capture and computerized data reduction programs are used. Calculations are either performed using commercial software (counting system operating systems) or TBE developed and validated software is used (see 7.4 below). Analysis of reduced data is performed as described in Section 14.0 and Procedure 4004.

7.4 Verification of Technical Processes, Methods, and Software 7.4.1 Operational Flow Verification The entire QA Manual and related procedures describe the verification of elements of the technical process flow and the establishment of quality check points, reviews, and controls.

7.4.2 Method Verifications Methods are verified and validated per Procedure 4007 prior to use unless otherwise agreed to by the client. For most TBE methods initial validation occurred well in the past. New or significantly revised Methods receive initial validation by demonstration of their performance using known analytes (NIST traceable) in appropriate matrices. Sufficient samples are run to obtain statistical data that provides evidence of process capability and control, establishes detection levels (see procedure 4009), bias and precision data (see Procedure 4011). All method procedures and validation data are available to respective clients. Also see Section 7.5 below for the Demonstration of Capability program.

7.4.3 Data Reduction and Analysis Verification Data reduction and analysis verification is performed by personnel who did not generate the data. (See Section 14.0).

7.5 Design of Quality Controls Page 18 of 32

7.5.1 General There are multiple quality controls designed into the laboratory operations.

Many of these are described elsewhere in this manual and include personnel qualification (Section 4.0), Document control (6.0), Sample identification and control (9.0), Use of reference standards (10.0), intra- and inter- laboratory tests (10.0), etc.

This Section describes the basic quality control systems used to verify Method capability and performance.

7.5.2 Demonstration of Capability (D of C)

The demonstration of capability system verifies and documents that the method, analyst, and the equipment can perform within acceptable limits. The D of C is certified for each combination of analyte, method, and instrument type. D of C's are certified based on objective evidence at least annually. This program is combined with the analyst D of C program (See Section 4.0). Initial D of C's use the method validation effort as covered above. Subsequent D of C's use Inter-Laboratory samples (Procedure 4006) or, if necessary, laboratory generated samples using NIST traceable standards. If results are outside of control limits, re-demonstration is required after investigation and corrective action is accomplished (See Sections 12.0 and 13.0) 7.5.3 Process Control Checks Process control checks are designed to include Inter-Lab samples, Intra-lab QC check samples, and customer provided check samples. 10% of laboratory analysis samples are for process control purposes.

7.5.3.1 Inter- Lab Samples. Inter-lab samples are procured or obtained from sources providing analytes of interest in matrices similar to normal client samples. These samples may be used for Demonstration of Capability of analyst's, equipment and methods. They also provide for independent insight into the lab's process capabilities. Any value reported as being in the warning zone (over 2 sigma) is reviewed and improvements taken. Any value failing (over 3 sigma) is documented on an NCR and formal investigation per Section 12.0 and 13.0 is performed. If root causes are not clearly understood and fixed, re-tests are required using lab prepared samples (See Procedure 4006).

7.5.3.2 QC Samples. QC samples, along with Inter-lab samples and customer check samples, are 10% of the annual lab workload for the applicable analyte and method. If batch processing is used, some specifications require specific checks with each batch or each day rather than as continuous process controls.

(See Procedure 4005)

QC samples consist of multiple types of samples including:

(a) Method blanks (b) Blank spikes (c) Matrix spikes Page 19 of 32

(d) Duplicates (e) Tracers and carriers Acceptance limits for these samples are given in Procedures or in lab standards. The number, frequency, and use of these sample types varies with the method, matrix, and supplemental requirements. The patterns of use versus method and the use of the resulting test data is described in Procedure 4005.

7.5.3.3 Customer Provided Check Samples. Customers may provide blind check samples and duplicates to aid in their evaluation of the Laboratory. When the lab is notified that samples are check samples their results are included in the QC sample percentage counts. Any reported problems are treated as formal complaints and investigated per Section 5.

7.6 Counting Instrument Controls The calibration of instruments is their primary control and is described in Section 11.0. In addition, counting procedures (3000 series) also specify use of background checks (method blank data is not used for this) to evaluate possible counting equipment contamination. Instrument calibration checks using a lab standard from a different source than the one used for calibration are also used.

Background data can be used to adjust client and test data. Checks with lab standards indicate potential calibration changes.

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8.0 PURCHASING AND SUBCONTRACT CONTROLS 8.1 General Procurement and Subcontracts efforts use the Huntsville-based Cost Point computer system to process orders. The Laboratory-generated Purchase Requisitions are electronically copied into Purchase Orders in Huntsville. The Laboratory also specifies sources to be used. Procured items and services are received at the Laboratory where receiving checks and inspections are made.

Laboratory Procedure 1015 provides details on the procurement control system at the Laboratory and references the Huntsville procedures as applicable.

8.2 Source Selection Sources for procurements of items and services are evaluated and approved by QA as described in Procedure 1015. Nationally recognized catalog item sources are approved by the QA Manager based on reputation. Maintenance services by an approved distributor or the equipment manufacturing company are pre-approved.

Sources for other services are evaluated by QA, based on service criticality to the quality system, by phone, mail out, or site visit.

Subcontract sources for laboratory analysis services are only placed with accredited laboratories (by NELAP, NUPIC, State, Client, etc.) as applicable for the type of analysis to be performed. QA maintains lists of approved vendors and records of evaluations performed.

8.3 Procurement of Supplies and Support Services 8.3.1 Catalog Supplies The Laboratory procures reagents, processing chemicals, laboratory glassware, consumables, and other catalog items from nationally known vendors and to applicable laboratory grades, purities, concentrations, accuracy levels, etc.

Purchase Requisitions for these items specify catalog numbers or similar call-outs for these off-the-shelf items. Requisitions are generated by the personnel in the lab needing the item and are approved by the Operations or Production Manager.

Reagents are analytical reagent grade only.

8.3.2 Support Services Purchase Requisitions for support services (such as balance calibration, equipment maintenance, etc.) are processed as in 8.3.1 but technical requirements are specified and reviewed before approvals are given.

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8.3.3 Equipment and Software Purchase Requisitions for new equipment, software programs, and major facility modifications affecting the quality system are reviewed and approved by the Operations Manager and the QA Manager.

8.4 Subcontracting of Analytical Services When necessary, the Laboratory may subcontract analytical services required by a client. This may be because of special needs, infrequency of analysis, etc.

Applicable quality and regulatory requirements are imposed in the Purchase Requisition and undergo a technical review by QA. TBE reserves the right of access by TBE and our client for verification purposes.

8.5 Acceptance of Items or Services Items and services affecting the quality system are verified at receipt based on objective evidence supplied by the vendor. Supply items are reviewed by the requisitioner and, if acceptable, are accepted via annotation on the vendor packing list or similar document. Similarly, equipment services are accepted by the requisitioning lab person. Calibration services are accepted by QA based on certification reviews. (See Section 11.0.)

Data reports from analytical subcontractors are evaluated by Program Managers and subsequently by the Operations Manager (or designee) as part of client report reviews.

Items are not used until accepted and if items or services are rejected, QA is notified and nonconformance controls per Section 12.0 are followed. Vendors may be removed from the approved vendors list if their performance is unacceptable.

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9.0 TEST SAMPLE IDENTIFICATION AND CONTROL 9.1 Sample Identification Incoming samples are inspected for customer identification, container condition, chain of custody forms, and radioactivity levels. If acceptable, the sample information is entered into LIMS which generates bar coded labels for attachment to the sample(s). The labels are attached and samples stored in the assigned location.

If environmental controls are needed (refrigeration, freezing, etc.), the samples are placed in these storage locations. If not acceptable, the Program Manager is notified, the customer contacted, and the problem resolved (return of sample, added data receipts, etc.). See Procedure 4003 for more information on sample receipt.

9.2 LIMS The LIMS is used to schedule work, provide special information to analysts, and record all actions taken on samples. See Procedure 4017 and the 6000 series of procedures for more information on LIMS operations.

9.3 Sample Control The sample, with its bar coded label, is logged out to the applicable lab operation where the sample is processed per the applicable methods (Procedures 2000 and 3000). The LIMS-assigned numbers are used for identification through all operations to record data. Data is entered into LIMS, log books (kept by the analysts) or equipment data systems to record data. The combination of LIMS, logbooks, and equipment data systems provide the Chain of Custody data and document all actions taken on samples. Unused sample portions are returned to its storage area for possible verification use. Samples are discarded after required time limits are passed and after client notification and approval, if required.

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10.0 SPECIAL PROCESSES, INSPECTION, AND TEST 10.1 Special Processes The Laboratorys special processes are the methods used to analyze a sample and control equipment. These methods are defined in Procedures in the 2000 and 3000 series. These processes are performed to the qualified methods (see Section 7.0) by qualified people (see 4.0).

10.2 Inspections and Tests The quality of the process is monitored by indirect means. This program involves calibration checks on counting equipments (see Section 11.0), intra-laboratory checks, and inter-laboratory checks. In addition, some customers submit quality control check samples (blinds, duplicates, external reference standards). All generated data gets independent reviews.

10.2.1 Intra Laboratory Checks (QC Checks)

The quantity and types of checks varies with the method, but basic checks which may include blanks, spiked blanks, matrix spikes, matrix spike duplicates, and duplicates are used as appropriate for customer samples. This process is described in Procedure 4005 and in Section 7.0.

10.2.2 Inter Laboratory Checks TBE participates in Inter-lab performance evaluation (check) programs with multiple higher level labs. These programs provide blind matrices for the types of matrix/analyte combinations routinely processed by the Lab, if available. This program is described in Procedure 4006.

10.2.3 Data Reviews Raw data and reports are reviewed by the Operations Manager, or designees. This review checks for data logic, expected results, procedure compliance, etc. (See Section 14.0).

10.3 Control of Sampling of Samples Samples for analysis are supplied by customers preferably in quantities sufficient to allow re-verification analyses if needed. The samples are prepared for analysis by analysts and then an aliquot (partial sample extraction) is taken from the homogeneous customer sample for the initial analysis. Methods specify standard volumes of sample material required. Sampling data is recorded in LIMS and/or logbooks.

10.4 Reference Standards / Material Page 24 of 32

10.4.1 Weights and Temperatures Reference standards are used by the Laboratorys calibration vendor to calibrate the Labs working instruments measuring weights and thermometers.

10.4.2 Radioactive Materials Reference radioactive standards, traceable to NIST, are procured from higher level laboratories. These reference materials are maintained in the standards area and are diluted down for use by laboratory analysts. All original and diluted volumes are fully traceable to source, procedure, analyst, dilution, and acquisition dates. See Section 11.0 and Procedure 1009.

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11.0 EQUIPMENT MAINTENANCE AND CALIBRATION 11.1 General There are two types of equipment used by the Laboratory: support equipment (scales, glassware, weights, thermometers, etc.) and instruments for counting. Standards traceable to NIST are used for calibration and are of the needed accuracy for laboratory operations. Procedures 1009, 4018, and 4019 describe the calibration and maintenance programs.

11.2 Support Equipment Analytical support equipment is purchased with the necessary accuracies and appropriate calibration data. If needed, initial calibration by the Laboratory or its calibration vendor is performed. Recalibration schedules are established and equipment recalibrated by the scheduled date by a calibration vendor or by Laboratory personnel. Maintenance is performed, as needed, per manufacturers manuals or lab procedures.

In addition to calibrations and recalibrations, checks are made on the continued accuracy of items as described in Procedure 1009. Records are maintained of calibration and specified checks.

11.3 Instruments Instruments receive initial calibration using radioactive sources traceable to NIST. The initial calibration establishes statistical limits of variation that are used to set control limits for future checks and recalibration. This process is described in Procedure 4018. Instruments are maintained per Instrument Manual requirements.

Recalibrations are performed per the Procedure.

Between calibrations, check sources are used to assure no significant changes have occurred in the calibration of items. Background checks are performed to check for possible radioactive contamination. Background values are used to adjust sample results. Hardware and software are safeguarded from adjustments that could invalidate calibrations or results.

11.4 Nonconformances and Corrective Actions If calibrations or checks indicate a problem, the nonconformance system (Section 12.0) and corrective action system (Section 13.0) are initiated to document the problem and its resolution. Equipment is promptly removed from service if questionable.

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11.5 Records Records of calibrations are maintained. Calibration certificates from calibration vendors are maintained by QA. Other calibration data and check data is maintained in log books, LIMS, or instrument software as appropriate and as described in Procedures 1009, 4018, and 4019.

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12.0 NONCONFORMANCE CONTROLS 12.1 General The nonconformance control system is implemented whenever a nonconforming condition on any aspect of Laboratory analysis, testing, or results exist. The system takes graded actions based on the nature and severity of the nonconformance. Nonconforming items or processes are controlled to prevent inadvertent use. Nonconformances are documented and dispositioned. Notification is made to affected organizations, including clients. Procedure 1010 describes the procedures followed. Sample results are only reported after resolution.

12.2 Responsibility and Authority Each Laboratory employee has the responsibility to report nonconformances and the authority to stop performing nonconforming work or using nonconforming equipment. Laboratory supervision can disposition and take corrective actions on minor problems. Any significant problem is documented by QA using the Laboratorys NCR system per Procedure 1010. QA conducts or assures the conduct of cause analyses, disposition of items or data, and initiation of corrective action if the nonconformance could recur.

12.3 10CFR21 Reporting The QA Manager reviews NCRs for possible need of customer and/or NRC notification per the requirements of 10CFR21. Procedure 1011 is followed in this review and for any required reporting.

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13.0 CORRECTIVE AND PREVENTIVE ACTIONS 13.1 General The Laboratory takes corrective actions on significant nonconformances (see Section 12.0). It also initiates preventive and improvement actions per the Company Quality Policy (see Section 2.0). The procedures for Corrective Action/Preventive Action systems are contained in Procedure 1012.

13.2 Corrective Actions Corrective actions are taken by Operations and Quality to promptly correct significant conditions adverse to quality. The condition is identified and cause analysis is performed to identify root causes. Solutions are evaluated and the optimum one selected that will prevent recurrence, can be implemented by the Laboratory, allows the Laboratory to meet its other goals, and is commensurate with the significance of the problem. All steps are documented, action plans developed for major efforts, and reports made to Management. QA verifies the implementation effectiveness. Procedure 1012 provides instructions and designates authorities and responsibilities.

13.3 Preventive Actions Preventive actions are improvements intended to reduce the potential for nonconformances. Possible preventive actions are developed from suggestions from employees and from analysis of Laboratory technical and quality systems by management. If preventive actions or improvements are selected for investigation, the issues, investigation, recommendations, and implementation actions are documented. Follow up verifies effectiveness.

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14.0 RESULTS ANALYSIS AND REPORTING 14.1 General The Laboratorys role is to provide measurement-based information to clients that is technically valid, legally defensible, and of known quality.

14.2 Results Review The results obtained from analytical efforts are collected and reviewed by the Operations Manager and the Program Manager. This review verifies the reasonableness and consistency of the results. It includes review of sample and the related QC activity data. Procedure 4002 describes the process. Any deficiencies are corrected by re-analyses, recalculations, or corrective actions per Sections 12.0 and 13.0. Use of the LIMS with its automatic data loading features (see Procedure 4017) minimizes the possibility of transcription or calculation errors.

14.3 Reports Reports range from simple results reporting to elaborate analytical reports based on the client requirements and imposed specifications and standards. (See Procedure 4004.) Reports present results accurately, clearly, unambiguously, objectively, and as required by the applicable Method(s). Reports include reproduction restrictions, information on any deviations from methods, and any needed data qualifiers based on QC data. If any data is supplied by analytical subcontractors (see Section 8.0), it is clearly identified and attributed to that Laboratory by either name or accreditation number.

If results are faxed or transmitted electronically, confidentiality statements are included in case of receipt by other than the intended client.

Reports are approved by the Program Manager and Operations Manager and record copies kept in file (See Section 15.0).

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15.0 RECORDS 15.1 General The Laboratory collects generated data and information related to quality or technical data and maintains them as records. Records are identified, prepared, reviewed, placed in storage, and maintained as set forth in Procedure 1003.

15.2 Type of Records All original observations, calculations, derived data, calibration data, and test reports are included. In addition QA data such as audits, management reviews, corrective and preventive actions, manuals, and procedures are included.

15.3 Storage and Retention Records are stored in files after completion in the lab. Files are in specified locations and under the control of custodians. Filing systems provide for retrieval.

Electronic files are kept on Company servers (with regular back up) or on media stored in fireproof file cabinets. Records are kept in Laboratory files for at least 2 years after the last entry and then in Company files for another year as a minimum.

Some customers specify larger periods - up to 7 years - which is also met. Generic records supporting multiple customers are kept for the longest applicable period.

15.4 Destruction or Disposal Records may be destroyed after the retention period and after client notification and acceptance, if required. If the Laboratory closes, records will go in to company storage in Huntsville unless otherwise directed by customers. If the Laboratory is sold, either the new owner will accept record ownership or the records will go into Company storage as stated above.

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16.0 ASSESSMENTS 16.1 General Assessments consist of internal audits and management reviews as set forth in Procedure 1013.

16.2 Audits Internal audits are planned, performed at least annually on all areas of the quality system, and are performed by qualified people who are as independent as possible from the activity audited. (The Laboratorys small size inhibits full independence in some technical areas.) Audits are coordinated by the Quality Manager who assures audit plans and checklists are generated and the results documented. Reports include descriptions of any findings and provide the auditors assessment of the effectiveness of the audited activity. Report data includes personnel contacted.

Audit findings are reviewed with management and corrective actions agreed to and scheduled. Follow up is performed by QA to verify accomplishment and effectiveness of the corrective action.

16.3 Management Reviews The Annual Quality Assurance Report, prepared for some clients, is the Management Review vehicle. These reports cover audit results, corrective and preventive actions, external assessments, and QC and inter-laboratory performance checks. The report is reviewed with Management by the QA Manager for the continued suitability of the Quality Program and its effectiveness. Any needed improvements are defined, documented, and implemented. Follow ups are made to verify implementation and effectiveness.

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Revision 0 APPENDIX D LABORATORY ANALYTICAL REPORTS 045136 (16) LaSalle Generating Station

L28614 1 of 61 L28614 2 of 61 L28614 3 of 61 L28614 4 of 61 L28614 5 of 61 L28614 6 of 61 L28614 7 of 61 L28614 8 of 61 L28614 9 of 61 L28614 10 of 61 L28614 11 of 61 L28614 12 of 61 L28614 13 of 61 L28614 14 of 61 L28614 15 of 61 L28614 16 of 61 L28614 17 of 61 L28614 18 of 61 L28614 19 of 61 L28614 20 of 61 L28614 21 of 61 L28614 22 of 61 L28614 23 of 61 L28614 24 of 61 L28614 25 of 61 L28614 26 of 61 L28614 27 of 61 L28614 28 of 61 L28614 29 of 61 L28614 30 of 61 L28614 31 of 61 L28614 32 of 61 L28614 33 of 61 L28614 34 of 61 L28614 35 of 61 L28614 36 of 61 L28614 37 of 61 L28614 38 of 61 L28614 39 of 61 L28614 40 of 61 L28614 41 of 61 L28614 42 of 61 L28614 43 of 61 L28614 44 of 61 L28614 45 of 61 L28614 46 of 61 L28614 47 of 61 L28614 48 of 61 L28614 49 of 61 L28614 50 of 61 L28614 51 of 61 L28614 52 of 61 L28614 53 of 61 L28614 54 of 61 L28614 55 of 61 L28614 56 of 61 L28614 57 of 61 L28614 58 of 61 L28614 59 of 61 L28614 60 of 61 L28614 61 of 61 L28786 1 of 98 L28786 2 of 98 L28786 3 of 98 L28786 4 of 98 L28786 5 of 98 L28786 6 of 98 L28786 7 of 98 L28786 8 of 98 L28786 9 of 98 L28786 10 of 98 L28786 11 of 98 L28786 12 of 98 L28786 13 of 98 L28786 14 of 98 L28786 15 of 98 L28786 16 of 98 L28786 17 of 98 L28786 18 of 98 L28786 19 of 98 L28786 20 of 98 L28786 21 of 98 L28786 22 of 98 L28786 23 of 98 L28786 24 of 98 L28786 25 of 98 L28786 26 of 98 L28786 27 of 98 L28786 28 of 98 L28786 29 of 98 L28786 30 of 98 L28786 31 of 98 L28786 32 of 98 L28786 33 of 98 L28786 34 of 98 L28786 35 of 98 L28786 36 of 98 L28786 37 of 98 L28786 38 of 98 L28786 39 of 98 L28786 40 of 98 L28786 41 of 98 L28786 42 of 98 L28786 43 of 98 L28786 44 of 98 L28786 45 of 98 L28786 46 of 98 L28786 47 of 98 L28786 48 of 98 L28786 49 of 98 L28786 50 of 98 L28786 51 of 98 L28786 52 of 98 L28786 53 of 98 L28786 54 of 98 L28786 55 of 98 L28786 56 of 98 L28786 57 of 98 L28786 58 of 98 L28786 59 of 98 L28786 60 of 98 L28786 61 of 98 L28786 62 of 98 L28786 63 of 98 L28786 64 of 98 L28786 65 of 98 L28786 66 of 98 L28786 67 of 98 L28786 68 of 98 L28786 69 of 98 L28786 70 of 98 L28786 71 of 98 L28786 72 of 98 L28786 73 of 98 L28786 74 of 98 L28786 75 of 98 L28786 76 of 98 L28786 77 of 98 L28786 78 of 98 L28786 79 of 98 L28786 80 of 98 L28786 81 of 98 L28786 82 of 98 L28786 83 of 98 L28786 84 of 98 L28786 85 of 98 L28786 86 of 98 L28786 87 of 98 L28786 88 of 98 L28786 89 of 98 L28786 90 of 98 L28786 91 of 98 L28786 92 of 98 L28786 93 of 98 L28786 94 of 98 L28786 95 of 98 L28786 96 of 98 L28786 97 of 98 L28786 98 of 98 L28801 1 of 130 L28801 2 of 130 L28801 3 of 130 L28801 4 of 130 L28801 5 of 130 L28801 6 of 130 L28801 7 of 130 L28801 8 of 130 L28801 9 of 130 L28801 10 of 130 L28801 11 of 130 L28801 12 of 130 L28801 13 of 130 L28801 14 of 130 L28801 15 of 130 L28801 16 of 130 L28801 17 of 130 L28801 18 of 130 L28801 19 of 130 L28801 20 of 130 L28801 21 of 130 L28801 22 of 130 L28801 23 of 130 L28801 24 of 130 L28801 25 of 130 L28801 26 of 130 L28801 27 of 130 L28801 28 of 130 L28801 29 of 130 L28801 30 of 130 L28801 31 of 130 L28801 32 of 130 L28801 33 of 130 L28801 34 of 130 L28801 35 of 130 L28801 36 of 130 L28801 37 of 130 L28801 38 of 130 L28801 39 of 130 L28801 40 of 130 L28801 41 of 130 L28801 42 of 130 L28801 43 of 130 L28801 44 of 130 L28801 45 of 130 L28801 46 of 130 L28801 47 of 130 L28801 48 of 130 L28801 49 of 130 L28801 50 of 130 L28801 51 of 130 L28801 52 of 130 L28801 53 of 130 L28801 54 of 130 L28801 55 of 130 L28801 56 of 130 L28801 57 of 130 L28801 58 of 130 L28801 59 of 130 L28801 60 of 130 L28801 61 of 130 L28801 62 of 130 L28801 63 of 130 L28801 64 of 130 L28801 65 of 130 L28801 66 of 130 L28801 67 of 130 L28801 68 of 130 L28801 69 of 130 L28801 70 of 130 L28801 71 of 130 L28801 72 of 130 L28801 73 of 130 L28801 74 of 130 L28801 75 of 130 L28801 76 of 130 L28801 77 of 130 L28801 78 of 130 L28801 79 of 130 L28801 80 of 130 L28801 81 of 130 L28801 82 of 130 L28801 83 of 130 L28801 84 of 130 L28801 85 of 130 L28801 86 of 130 L28801 87 of 130 L28801 88 of 130 L28801 89 of 130 L28801 90 of 130 L28801 91 of 130 L28801 92 of 130 L28801 93 of 130 L28801 94 of 130 L28801 95 of 130 L28801 96 of 130 L28801 97 of 130 L28801 98 of 130 L28801 99 of 130 L28801 100 of 130 L28801 101 of 130 L28801 102 of 130 L28801 103 of 130 L28801 104 of 130 L28801 105 of 130 L28801 106 of 130 L28801 107 of 130 L28801 108 of 130 L28801 109 of 130 L28801 110 of 130 L28801 111 of 130 L28801 112 of 130 L28801 113 of 130 L28801 114 of 130 L28801 115 of 130 L28801 116 of 130 L28801 117 of 130 L28801 118 of 130 L28801 119 of 130 L28801 120 of 130 L28801 121 of 130 L28801 122 of 130 L28801 123 of 130 L28801 124 of 130 L28801 125 of 130 L28801 126 of 130 L28801 127 of 130 L28801 128 of 130 L28801 129 of 130 L28801 130 of 130 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 L29178 R1 Revision 0 APPENDIX E DATA VALIDATION MEMORANDUM 045136 (16) LaSalle Generating Station