ML052010668
| ML052010668 | |
| Person / Time | |
|---|---|
| Site: | Saxton File:GPU Nuclear icon.png |
| Issue date: | 07/31/2005 |
| From: | GPU Nuclear Corp |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML052010668 (23) | |
Text
Final Status Survey Report For Saxton Nuclear Experimental Corporation Open Land Area Survey Units, OL6 and OL10 The Saxton Coal Fired Steam Generating Station - Photo from Operational Period Prepared by GPU Nuclear, Inc.
July 2005
Final Status Survey Report - Open Land Area OL6 and OLIO Table of Contents Section No.
Page Executive Summary............................................................................................................
I
1.0 Purpose and Scope
3 2.0 Survey Area Description............................................
3,,,,,,,,,,,,......
3 3.0 Operating History.................................................
4,,,,,,,,,,,,......
4 3.1 OL-6IOLIO Area Use.4 3.2 OL6OL10 Open Land Area Remediation Status
.5 3.3 SNEC Facility Operating History...................................................,,,,,,,,..
5 4.0 Site Release Criteria 6
4.1 OL6I0LIO Area Specific DCGLw Values 6
5.0 Final Status Survey Design/DQO Process.
7 5.1 Description of Survey Units 8
5.2 Survey Design for the OL61OL10 Open Land Area.9 6.0 Final Status Survey Results.....................................................................................
10 6.1 Summary of Survey Results for the OL6/OLIO Open Land Areas 10 6.2 OL6 Random Start Triangular Grid Systematically Spaced Soil Samples 1 1 6.3 OLIO-1 Random Start Triangular Grid Systematically Spaced Soil Samples...12 6.4 OL10-2 Random Start Triangular Grid Systematically Spaced Soil Samples.13 6.5 OLIO-3 Random Start Triangular Grid Systematically Spaced Soil Samples..,14 7.0 Data Assessment 15 7.1 Assessment Criteria 15 7.2 Survey Variations (Design, Survey Request, LTP)......................................
16 7.2.1 OL10-2 Mounded Area Sampling..................................................
16 7.2.2 Sampling Depth Less Than One Meter 16 7.2.3 Altered Survey/Sampling Locations..........................................
16 7.2.4 Scan Locations Around Class I Areas 16 7.3 Quality Control Measurements 16 7.4 A ssessm ent Sum m ary....................................................................................
17 8.0 Final Status Survey Conclusions 17 9.0 References 18 i
Final Status Survey Report-Open Land Area OL6 and OL10 Table of Contents (Continued)
Section No.
Page 10.0 Appendices 10.1 Appendix A SNEC Calculation No. E900-05-027, '0L6 and OL10 Open Land Area - Survey Design", April 22, 2005.
10.2 Appendix A Survey Request Results Summary for SR-0216 (0L6) 10.3 Appendix A Survey Request Results Summary for SR-0217 (OL10-1) 10.4 Appendix A Survey Request Results Summary for SR-0218 (OL10-2) 10.5 Appendix A Survey Request Results Summary for SR-0219 (OL1 0-3) ii
Final Status Survey Report - Open Land Area OL6 and OLI0 List of Figures Figure No.
Title Page 1
The Saxton Coal Fired Steam Generating Station - Photo from Operational Period Cover 2
SNEC Facility Site Area Grid Map Showing The Location Of OL6 & OL10 Areas 1
3 Photo of Empty Reagent Jars Found in One OLIO Survey Unit 4
iii
Final Status Survey Report - Open Land Area OL6 and OL10 List of Tables Table No.
Title Page 1
0L6 and OL10 - DCGLw Values 7
2 DQO/Design Parameters/Results 8
3 0L6 - SR-216 Sample Results 11 4
0L6 - SR-216 Alarm Point Investigation Results 11 5
OL10 SR-217 Sample Results 12 6
OL10 SR-217 Alarm Point Investigation Results 12 7
OL10 SR-218 Sample Results 13 8
OL10 SR-219 Sample Results 14 iv
Final Status Survey Report - Open Land Area OL6 and OL10 Executive Summary This report presents the results and conclusions of the Final Status Survey (FSS) conducted by GPU Nuclear, Inc. within the SNEC facility 0L6 and OL10 open land areas (survey units 0L6, OL10-1, OL10-2 and 0L10-3). This report provides summary results from volumetric scanning and sampling of soils within the aforementioned areas. This survey work was performed in May of 2005. All survey work was performed in accordance with the SNEC License Termination Plan (LTP) (Reference 9.1).
I MA4 MA3 OL6 & OL 10 OPEN LAND SURVEY UNITS OL10 O~OLO* j7s/5
=_
670
//
IIL ri liL9 L
Figure 2, A section of the SNEC Facility site grid map showing the location of the 0L6 and OL10 survey units.
Survey data was collected from the 0L6, OL1-0-1, OL10-2 and OL10-3 survey units according to data collection requirements specified in the survey design (Reference 9.2 and Appendix A-1).
During FSS activities, the following types of measurements were performed on materials found in these areas.
- 1. Nal detector scanning measurements were performed in approximately 6,800 m2 of the OL10-1 area, 6,860 m2 of the OL10-2 area, and 7,000 m2 of the OL10-3 area. In addition, 1,775 m2 of the 0L6 area was scanned. The OL10 survey units are considered Class 2-survey units and the 0L6 area is a Class 1-survey unit. Scan coverage requirements for these survey units are provided in Reference 9.1, Table 5-5.
- 2. Not counting quality control and replicate sampling, a total of twenty (20) soil/soil-like samples were obtained from the 0L6 survey unit. In addition, eighteen (18) samples 1
Ccii
Final Status Survey Report - Open Land Area OL6 and OL 0 were collected in the OL10-1 survey unit, twenty five (25) samples were selected from the OL10-2 survey unit, and fifteen (15) samples were taken in the OL10-3 survey unit.
All sample locations were selected using the random start, triangular grid systematic spacing methodology. Every sample was analyzed by gamma-ray spectroscopy to determine the presence of radionuclides that resulted from SNEC facility operations.
Two (2) quality control samples were taken in each survey unit, and Cs-137 is used as the surrogate radionuclide of interest.
FSS scan survey results were less than the action level for most of the applicable areas described in this report. Two (2) small areas exceeded the assigned alarm point of > 350 gross counts per minute (gcpm), using a 2" by 2" sodium iodide detector. When sampled, no analysis result from samples collected in either of the two alarm point locations exceeded the DCGLw.
All soil and soil-like material samples taken at every sampling depth from every survey unit, were below the applicable DCGLw. Therefore, this collection of FSS data demonstrate that these survey units meet the radiological criteria for unrestricted use specified in 10 CFR 20.1402 (Reference 9.3).
Based on the results of this final status survey effort, GPU Nuclear, Inc. concludes that the 0L6 and OL10 open land areas meet the NRC requirements for release to unrestricted use.
2
Final Status Survey Report - Open Land Area OL6 and OLIO
1.0 Purpose and Scope
This report presents the results and conclusions of the final status survey performed on the following areas:
Open Land Survey Unit 0L6 - Class 1 areas Open Land Survey Unit OL10-1, OL10-2 and OL10 Class 2 areas This survey effort provides the information required by 10 CFR 50.82(a)(1 1) (Reference 9.4) and SNEC's License Termination Plan (LTP), and demonstrate that this area meets the radiological criteria for unrestricted use specified in 10 CFR 20.1402.
2.0 Survey Area Description The open land areas of OL6 and OL10 reside north and northeast of the former SNEC Containment Vessel location. Collectively, these areas are approximately 22,435 square meters and are divided into both Class 1 and Class 2-survey units. These survey units are contained in the area enclosed by site grid markers AZ-131 and BS-131 on the west, and on the east by grid markers AZ-90, and BS-90 (Reference 9.5).
All together, OL6 is composed of three small areas that total about 1,775 square meters.
These three areas are collectively one (1) survey unit designated OL6. Each one of these OL6 areas is encompassed in one of the three OL10 survey units. The OL10 survey area is divided into the three (3) survey units listed below:
- OL10-l -6,800 square meters OL10 6,860 square meters OL10-3 -7,000 square meters All of these areas are sparsely covered with grass, trees, boulders and small shrubs. Soils from these areas contain a significant quantity of Saxton Steam Generating Station (SSGS) fly ash and coal dirt. Unpaved roads pass through and along these areas, and roadway composition is the same as the surrounding soil/soil-like materials. OL10-3 surrounds the former OL5 dumpsite, and a large amount of OL10 borders the Raystown Branch of the Juniata River. In OL10-2, an elevation change of about three (3) meters or more occurs near the site's 118 vertical grid line and extends to about the 109 vertical grid marker. This elevation change begins gradually in the south at about the BK horizontal grid line and continues north to the riverbank where a steep drop-off ends at the river 3
Final Status Survey Report - Open Land Area OL6 and OL1 0 below. Exploration and characterization efforts in and near this mounded area have exposed building debris and other man-made materials that were buried here from previous demolition activities that included the SSGS and SNEC Nuclear facilities.
Characterization results have not shown any elevated Cs-137 concentrations in these materials at any depth in the OL1 0 survey units, but the 0L6 areas that are encompassed by the OL10 survey units have been remediated.
3.0 Operating History 3.1 OL6/OL10 Area Use The SNEC Historical Site Assessment (HSA) (Reference 9.6, page 30) discusses the discovery of miscellaneous materials and artifacts in the Northeast Dumpsite area (0L5).
The SNEC facilities investigations of the OL6/OL10 areas have confirmed that similar materials were buried in these areas. The presence of building debris, laboratory reagent containers, rusted drums, and asbestos indicate that at least part of the area was used as a burial site when the SSGS facility and the SNEC reactor site terminated operations.
These miscellaneous materials were identified during the characterization process, and for the most part, were determined to have no radiological consequence. However, the 0L6 area contained some contaminated materials that were identified and remediated down to a meter or more below the surface.
Figure 3. Photo of Empty Reagent Jars Found in One OLIO Survey Unit.
4
Final Status Survey Report - Open Land Area OL6 and OLI0 3.2 016/0L10 Open Land Area Remediation Status While no radiological remediation was performed in the OL10 area, remediation activities were used to lower the mean concentration of Cs-137 in the three small OL6 areas (see Figure 2), to a concentration less than the applicable DCGLw.
3.3 SNEC Facility Operating History The Saxton Nuclear Experimental Corporation (SNEC) facility featured a pressurized water reactor (PWR), which was licensed to operate at 23.5 megawatts thermal (23.5 MWth). The facility is owned by the Saxton Nuclear Experimental Corporation and is licensed by GPU Nuclear, Inc. The SNEC facility is maintained under a Title 10 Part 50 license and associated Technical Specifications. In 1972, the license was amended to possess but not operate the SNEC reactor.
The facility was build from 1960 to 1962 and operated from 1962 to 1972, primarily as a research and training reactor. After shutdown in 1972, the facility was placed in a condition equivalent to the current SAFSTOR status. Since then, it has been maintained in a monitored storage condition. The fuel was removed in 1972 and shipped to a (now DOE) facility at Savannah River, South Carolina, who is now the owner of the fuel. As a result of this, neither SNEC nor GPU Nuclear, Inc. has any further responsibility for the spent fuel from the SNEC facility.
The reactor, containment vessel and support buildings have all been removed from the site. The building and structures that supported reactor operation were partially decontaminated by 1974. In the late 1980's and through the 1990's, additional decontamination, disassembly and removal of the containment vessel support buildings, large and small components and other miscellaneous support equipment was complete.
By 1992 decontamination and dismantlement of the reactor support structures was complete. Large components such as the pressurizer, steam generator, and reactor vessel were removed in late 1998. The removal of the steel Containment Vessel (CV) (to - 4' below grade), and backfill was complete by late 2003. More recently, decontamination, disassembly and demolition of the remaining SNEC facility buildings including remnants of the coal fired Saxton Steam Generating Station (SSGS) has taken place. The SNEC facility is currently in the process of performing the Final Status Survey for unrestricted release leading to license termination.
5
Final Status Survey Report - Open Land Area OL6 and OL10 4.0 Site Release Criteria The site release criteria as applied to the 0L6 and OL10 open land areas, correspond to the radiological dose criteria for unrestricted use per 10 CFR 20.1402. The dose criteria is met "if the residual radioactivity that is distinguishable from background radiation results in a Total Effective Dose Equivalent (TEDE) to an average member of the critical group that does not exceed 25 mrem/yr, including that from groundwater sources of drinking water; and that the residual radioactivity has been reduced to levels that are as low as reasonably achievable (ALARA)."
Levels of residual radioactivity that correspond to the allowable dose and meet site or survey unit release criteria were derived by analyses using either the building occupancy (surface area) or resident farmer (volumetric) scenarios. The dose modeling for these scenarios is explained in Chapter 6 of the SNEC LTP, Revision 3. The derived concentration guideline levels (DCGLs) determined in the LTP form the basis for satisfying the site release criteria.
As described in Chapter 6 of the SNEC LTP (Reference 9.1), a correction to the gross activity DCGLw is made to address de-listed radionuclides and provide a reasonable SNEC established safety factor. The SNEC facility has instituted an administrative limit of 75% for the allowable dose (DCGL) for all measurement results. Thus the de-listed radionuclide dose is accounted for by using the 75% administrative limit.
4.1 OL6IOL10 Area Specific DCGLw Values Not counting quality control (QC) samples, at least eighty (80) samples were taken in and near the OL10 survey units during the most recent characterization campaign. Most of these results were at or near background levels for Cs-137, exhibiting a mean concentration of 0.45 +/- 0.33 pCi/g (see Appendix A-1, Attachment 8-1). Additionally, greater than thirty (30) samples were taken during remediation efforts in the 0L6 areas.
The mean concentration from thirty of these samples was 2.6 +/- 1.7 pCi/g Cs-137 (see Appendix A-1, Attachment 8-1). These values were used as variability input parameters for the Compass computer program (Reference 9.7).
Four (4) representative samples from within three adjacent areas (0L4, OL5 & 0L6) were sent to an off-site laboratory to obtain the analysis results for the eleven (11) radionuclides associated with SNEC decommissioning process (see Appendix A-1, Attachment 2-1 to 6
Final Status Survey Report - Open Land Area OL6 and OLIO 2-3). These results were decayed and pooled to provide the Cs-137 surrogate value shown in Table 1.
Table 1, OL6 and OLIO - DCGLw VALUES Volumetric DCGLw (pCl/g) for Cs-I 37 6.54 (4.9 A.L.) (mix is -99% Cs-137)
NOTE: A.L. is the site Administrative Limit (75% of the effective DCGLw for the area).
5.0 Final Status Survey Design/DQO Process Survey Designs (SD's) (Appendix A) are developed IAW applicable sections of the SNEC License Termination Plan (LTP) and site procedures (Reference 9.8). During development, characterization activities are reviewed along with any post-remediation survey or sampling activities (as applicable). Survey unit variability is established from the best available or most representative measurement and/or sampling result. The Compass computer program is then used to develop MDCscan parameters (for structural surfaces),
the number of survey or sampling points in each survey unit, and other DQO design parameters. For open land areas, methodology from NUREG-1507 (Reference 9.9) is used to calculate MDCscan values that are then input to the Compass computer program.
For structural surfaces, representative background values are extracted from previous measurements of non-impacted like-materials of similar age whenever possible. For open land areas, background concentrations of relevant SNEC radionuclides are not subtracted from sample data sets prior to developing individual survey unit surrogate levels (of Cs-137). Thus the effective DCGLw values for open land areas are conservatively biased.
For most survey units, the number of Compass calculated sample and/or survey locations are augmented to provide "more than the minimum required coverage". Sample and/or survey point locations are plotted on drawings of individual survey areas using the Visual Sample Plan (VSP) computer code (Reference 9.10). Diagrams showing sample and/or survey point locations are clearly depicted on survey maps along with any necessary physical dimensions from known site area landmarks. Diagrams are then provided to individual survey teams through the use of the Survey Request (SR's) procedure process (Reference 9.11). SR's are issued as field working guidance documents. Before implementation, all SD's and SR's are reviewed and approved by the SNEC RSO (or his representative). Data Quality Objectives (DQO's) for the OL6 and OL10 areas are presented in the following table.
7
Final Status Survey Report - Open Land Area OL6 and OL10 Table 2, DQO/Design ParameterslResults Survey Unit l
L6 l4 OLb OLf0-2 OL-103 Survey Design Calculation. No.
E900-05-027 SNEC Survey Request No.
SR-216 SR-217 SR-218 J
SR-219 Survey Area Classification Class 1 Class 2 Class 2 Class 2 Total Estimated Area in Survey Unit (m2) 1,775 6,800 6,860 7,000 Material Type Soil and Soil-like Materials Scanning Goal (M2) 1,775 (100%)
l 3,400 (50%)
l 3,430 (50%)
l 3,500 (50%/6)
Actual Area Scanned (M2)
-1,768(99.6%)
l -3,774 (55.5%) l -3,711 (54.1%) l -3,178(45.4%)
Applicable Statistical Test Sign Type I Decision Error (a) 0.05 Type II Decision Error ()
0.10 Gross Activity DCGLw (pCi/g Cs-137) 6.54 (4.9 A.L.)
LBGR (pCilg Cs-1 37) 2.6 4.4 4.4 4.4 Estimated v (pCig Cs-1 37) 1.7 0.33 0.33 0.33 Actual q From Survey Unjt(cpm) 0.22 0.13 0.07 0.04 A/a (Planning Value) 1.35 1.52 1.52 1.52 Samples Required by Compass 16 14 14 14 Samples Specified byVSP" 20 18 19 18 Estimated Scan MDC (pCi/g Cs-137) 5.97 Scan Speed (cmi/sec) 25 Survey Instrument Type.
L-2350-1, w/44-10 2 by 2 Nal with Cs-137 Window Setting Instrument counts/disintegration (cpm/mRlh) 2 206,000 Scanning Alarm Point (gcpm)
> 350 Detector Gap to Surface (inches) 4 A.L. is the SNEC Facility Administrative Limit (75% of the applicable DCGLw).
VSP is Visual Sample Plan. VSP is used to plot points on diagrams. Typically several additional points are added during this process to compensate for potential losses in the field.
... This instrument uses a narrow window detector setting that improves the signal to noise ratio for Cs-1 37.
5.1 Description of Survey Units Figure 2 shows that the 0L6 and OL10 areas are approximately 22,436 square meters in total area. 0L6 is actually three small areas that have been collectively surveyed as one survey unit named OL6. Survey units are generally formed by grouping contiguous site areas with a similar history or use, and the same classification or contamination potential.
These three (3) areas are enough alike in composition and location to be considered one survey unit. The three (3) 0L6 areas are surrounded by the OL10-1, OL10-2 and OL10-3 survey units, and are similar in composition except that each of these smaller areas required remediation.
8
Final Status Survey Report - Open Land Area OL6 and OL1 0 Native soil, cinders, coal ash, and significant quantities of building debris make up the majority of material types in these areas. However, OL10-2 and OL10-3 appear to contain more building debris than the OL10-1 area. The entire OL10 area borders the Raystown Branch of the Juniata River on the northern side and sections of this area exhibit a steep drop off that in some places reaches fifteen (15) or more meters above the river below.
Survey work at or near the edge of the bank area was considered to hazardous to perform. In the OL10-3 survey unit, three sample points that were part of the random start systematic triangular grid system were dropped rather than expose survey personnel to a fall hazard.
5.2 Survey Design for the OL61OL10 Open Land Areas The survey design for 0L6/OL10 areas is provided as Appendix A-1. Since the OL10 survey areas are Class 2 open land areas, the initial scanning goal was set at 50% of the total area available. Each of the three OL10 survey units contains a small section of the 0L6 survey unit. Scan locations in the Class 2 areas were judgmentally selected to border these Class 1 areas as shown in Appendix A-1, Attachment 5-1. The minimum percent of scan coverage obtained for any Class 2 survey unit (OL10-1, OL10-2 or OL10-3) was about 45%, which is considered adequate. The 0L6 survey unit is a Class 1 area, and 100% scan coverage is required for all three 0L6 locations. This assignment is in accordance with Reference 9.1, Table 5-5.
The number of random start, triangular grid, systematically spaced sample points were determined using the Compass computer program (Reference 9.7). The minimum number of sample points selected by Compass for any survey unit was fourteen (14) (for OL10-1, OL10-2 and OL10-3). Each sample was to be one meter in depth to match the site area dose model discussed in Chapter 6 of the SNEC LTP (Reference 9.1). In the mounded area of OL10-2, a deeper sampling regime was assigned. Sample collection in this area was to penetrate the mound and collect base soil materials at select sample locations. At some locations this required the use of a backhoe rather than an auger. All sample points were placed on survey maps of the 0L6/OL10 area using the Visual Sample Plan (VSP) computer code (Reference 9.10).
These locations can be seen in Appendix A-1, -1 through 7-6.
9
Final Status Survey Report - Open Land Area OL6 and OL10 6.0 Final Status Survey Results 6.1 Summary of Survey Results for OL6/OL10 Open Land Areas Approximately 50% of the three OL10 survey units were scanned during FSS activities (see Appendix A-2 through A-5). FSS scanning requirements for a Class 2 open land area are typically 10 to 100% (Reference 9.1, Table 5-5). In the Class 1 (0L6) areas, 100% of the available area was scanned which also meets the requirements of Reference 9.1. Therefore, all scan coverage requirements for these areas as listed in the survey design and the SNEC LTP have been met.
Two (2) instrument alarms were encountered in grid BI-125 (part of 0L6) and in the adjacent grid BH-125 (part of OL10-1). These alarm points were sampled along with the area around the alarm points to verify the Cs-137 concentration. These results are provided in Table 4 and 6, and shown that the applicable DCGLw has not been exceeded in either case. Since the DCGLw was not exceeded the Classifications for both areas are correct. No further actions were needed to show compliance with SNEC LTP requirements.
In all, well over one hundred (100) characterization and FSS samples have been taken in the OL10 survey units. No sample analysis result yielded values above the DCGLw in OL10 areas. On the other hand, OL6 areas were remediated because all three locations were radiologically contaminated above the DCGLw. Once decontamination efforts were complete however, no residual activity remained that exceeded the DCGLw. The sample data used to establish the variability of OL6 was taken during the remediation phase and as a result the variability of the survey unit was significantly elevated. Samples taken in OL6 during FSS activities show a significantly lower Cs-137 concentration and as a result the variability is greatly reduced (see Table 2 and Appendix A-1, Attachment 8-1).
All sampling depths were in accordance with the SNEC site dose model of one (1) meter, except as noted in Section 7.2.2. FSS sample data are provided in Table 3 through 8.
Note that the variability of FSS samples identified in Table 3 through 8 are below the initial variability estimate used in the survey-planning phase for all four (4) survey units (see Table 2 initial sigma values).
10
Final Status Survey Report - Open Land Area OL6 and OLIO 6.2 OL6 Random Start, Triangular Grid, Systematically Spaced Soil Sample Results Table 3 0L6 - SR-216 Sample Results Sample No. Grid No. Sample Point Cs-137 (pCi/g) Sample Depth i SXSL10396 B1-125 SP-1
<0.125 1 m 2 SXSL10397 J.1-125 SP-2 0.34 1 m 3 SXSL10398 BJ-124 SP-3
<0.127 1 m ISXSL10399 J.1-123 SP-4 0.13 1 m ISXSL10400 BK-125 SP-5 0.54 1 m lSXSL10401 BK-124 SP-6 0.81 1 m SXSL10402 BK-124 SP-6 (QC) 0.64 1 m SXSL10403 BK-123 SP-7
<0.18 1 m lSXSL10404 BL-125 SP-8 0.43 1 m 1 SXSL10405 BL-124 SP 9 0.22 1 m 11 SXSL10406 BL-123 SP 10 0.12 1 m 1 SXSL10409 BL-125 SP11
<0.122 I m 1 SXSL10410 BL-124 SP-12
< 0.0571 1 m 1 SXSL10411 BL-123 SP-13
<0.161 1 m 1 SXSL10412 BN-114 SP-14 0.36 1 m 11 SXSL10413 BN-113 SP 15
<0.089 -
1 m 1 SXSL10414 BN-112 SP-16
<0.121 1 m 11 SXSL1415 B0114 SP-17 0.66 1 m 1 SXSLI0416 B-112 SP-18 026 1 m 20 SXSL10417 BM-106 SP-19
<0.124 1 m 21 SXSL10418 BM-106 SP-19 (QC)
< 0.145 1 m SXSL10419 BN-106 SP-20
< 0.146 1 m Averageo 0 27 Sigma 0 228 l
~~Minimum-.6
_M Xaximum=.
0.81=
As stated previously, one alarm point (AP) was reached in the 0L6 survey unit surrounded by OL10-1 (see Figure 2). The alarm was reported as 529 to 623 gcpm, which is above the AP of > 350 gcpm. The AP was investigated by sampling the elevated area and several other locations at a one (1) meter radius around the AP. These sample results are provided in Table 4.
iT a m if:
< 0.515 1
I Im SP-2
<0.119 1 m SP-3 0.26 1 m Average=*
0.61_
I MInImum=-
0.t2 I
Maximum=*
t1.53 L
s Since all analysis results for Cs-137 were below the DCGLw, and are more typical of site background concentrations, no additional samples were taken. This area borders the alarm point found in the surrounding OL10-1 survey unit.
11
Final Status Survey Report - Open Land Area OL6 and OLI0 6.3 OL10-1 Results Random Start, Triangular Grid, Systematically Spaced Soil Sample Table 5. OL10 SR-217 Sample Results ll Sample No.
Grid No. Sample Point Cs-1 37 (pCUg) I Sample Depth 9
BE-124 SP-1
<0.121 1 m 0
BE-122 SP-2
< 0.104 1 m 1
BG-127 SP-3
< 0.142 1 m 2
BG-125 SP-4
<0.549 1 m 3
BG-123 SP-5 0.12 1 m 4
Bl-130 SP-6 0.19
-6" SYGM-5 Bl-128 SP-7 0.21
-6" SYGM' 6
Bl-126 SP-8 0.31 1 m 7
Bl-124 SP-9 0.20 1 m 9
Bl-122 SP-10
<0.109 1 m 0
Bl-120 SP-11 0.20 1 m 1
Bl-118 SP-12
<0.15 1 m SP-13
<0.106 1 m SP-14 0.13 I m SP-14 (QC) 0.11 1 m SP-15 0.50
-0.136 1 m
<0.118 I m Average-*
0.20_
Sigrna=*
O.t13
- 5 Minirnurn=
0.09_
Maximurn=2 0.55_
M = Switch Yard Grounding Mat Interference The alarm point (AP) found in the OL10-1 survey unit was reported as 468 to 498 gcpm, which is above the AP of > 350 gcpm. The AP was investigated by sampling the elevated area and several other locations at a one (1) meter radius around the AP. These sample results are provided in Table 6.
esults cpml Area m12
! 4'9 1
SP SP-SAver:g.
t lM=n
< 0.107 1.11
< 0.095 1.11 1.43 1m I m i m I
-n It A
Ulnimssm n nq i
.11.11, i
rlmum=>
4.1J 11-Analysis of samples taken in the areas where alarm points were exceeded were below the DCGLw for Cs-1 37. No additional samples were taken.
12
Final Status Survey Report - Open Land Area OL6 and OL10 6.4 OL10-2 Random Start, Triangular Grid, Systematically Spaced Soil Sample Results Table 7. OL0 SR-218 Samole Results
T V
Sample Point I Cs-i 37 foClIa)
Sample Depth Sampole Point I Cs-1 37 (pCi/g)
-Samp~le Depth BA-i17 SP-1 0.21 1 m BE-117 SP-2 0.10 1 m BE-115 SP-3 0.17 1 m BE-113 SP-4 0.24 1 m BG-112 SP-5 0.23 1 m B 81-117 SP-6 0.23 1 m 7
B-115 SP-7
< 0.126 1 nm 3
B-113 SP-8 0.17 1 m 3
B-111 SP-9 0.09 1 m BK-114 SP-11
<0.133 1 m 2
BK-1 16 SP-10 0.37 1 m. Base Soil 3
BK-112 SP-12A
<0.0697 1 m 4
BK-112 SP-12B
< 0.0923 2 m BK-112 SP-12C
< 0.0768 3 m, Max. Depth of Sampling Eq.
BO-116 SP-18A
< 0.129 1 m, Debris & Fill BO-116 SP-18B
< 0.0886 2 m, Debris & Fill 3 80-116 SP-18C
< 0.111 3 m, Max. Depth of Sampling Eq.
3 BM-113 SP-16A
<0.0926 1 m D
BM-113 SP-16B
< 0.105 2 m BM-113 SP-16C
< 0.0533 3 m. Max. Depth of Sampling Eq.
BK-110 SP-13
< 0.104 1 nm BM-117 SP-14 0.10 1 m BM-115 SP-15 0.16 1 m BM-111 SP-17
<0.105 1 nm SP-19
< 0.106 I m 110I SP-19 (C)
Average=
Slgma*
Mln mumo Maxlmum:
< 0.128 0.14 0.07 0.05 0.37 The OL1 0-2 area contains a mounded region that was previously described in Section 2.0.
In this area, one (1) meter sampling depths were augmented by additional samples taken down to base soil materials when ever possible. This same methodology was used during the characterization phase to explore and sample sections of the OL10-2 survey unit to ensure no hidden pockets of contaminated materials were at depths below one (1) meter.
The results of this multi-depth sampling effort are listed in Table 7. In some cases the track-hoe sampling equipment could not reach the base soil layer below the debris mound.
However, all samples collected during this process yielded Cs-137 values that were well below the DCGLw and this effort is considered adequate for this area.
13
Final Status Survey Report-Open Land Area OL6 and OL10 6.5 OL10-3 Random Start, Triangular Grid, Systematically Spaced Soil Sample Results Table 8. OL10 SR-219 Sample Results Ii 1.
4,
Sample No. Grid No. Sample Point Cs-137 (pClg)
Sample Depth I SXSL10449 BK-107 SP-1
<0.074 1 m SXSL10450 BK-105 SP-2
<0.0735 1 m 3 SXSL10451 BK-103 SP-3 0.15 0.5 m (Refusal)
SXSL10452 BK-101 SP-4
< 0.0797 1 m SXSL10453 BK-99 SP-5
< 0.129 1 m SXSL10454 BK-99 SP-5 (QC)
<0.133 1 m SXSL10455 BM-108 SP-6
<0.151 1 m SXSL10456 BM-104 SP-7
< 0.0599 1 m SXSL10457 BM-102 SP-8
< 0.0441 1 m SXSL10458 BO-107 SP-9
<0.0898 1 m I SXSL10459 BO-105 SP-10
<0.0663 1 m SXSL10460 BO-103 SP-11
<0.0766 1 m SXSL10461 BO-101 SP-12
<0.146 1 m SXSL10462 BO-99 SP-13 0.20 1 m SXSL10463 BO-99 SP-13 (QC)
< 0.119 1 m SXSL10464 BO-91 SP-17
<0.14 1 m
. SXSL10465 BM-91 SP-18
<0.0775 1 m Average 0.11_
Sigmar 0.04 Minlmumn 0.04 Maximum=l 0.20 NOTE: Sample points SP-14, SP-15 & SP-16 (not shown) deleted because of steep river bank location.
The OL10-3 area surrounds the Class 1 0L5 area that was the subject of extensive site clean-up efforts. The 0L5 area was a dumpsite where used industrial supplies and other miscellaneous materials were discarded. The boundary of the dumpsite was eventually identified and as a result, the Class 2 OL10-3 survey unit was established to buffer the OL5 area. The OL10-3 area also borders the river where a steep drop-off of about fifteen (15) meters or more ends at the river below. Survey work was limited in this area because of safety concerns. As a result, several samples that were part of the random start systematic spacing triangular grid system were not collected (see note at the base of Table 8).
Sample results from the OL10-3 survey unit did not show significant levels of Cs-137. In fact most of the FSS sample results from this area were below the minimum detectable concentration for Cs-1 37. As a result, this survey unit meets the release criteria.
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Final Status Survey Report - Open Land Area OL6 and OL1 0 7.0 Data Assessment 7.1 Assessment Criteria Final status survey data has been reviewed to verify authenticity, appropriate documentation, quality, and technical acceptability. The review criteria for data acceptability are:
- 1) The instruments used to collect the data were capable of detecting the radiation of the radionuclide of interest at or below the investigation levels.
- 2) The calibration of the instruments used to collect the data was current and radioactive sources used for calibration were traceable to recognized standards or calibration organizations.
- 3) Instrument response was checked before, and when required, after instrument use each day data was collected.
- 4) Survey team personnel were properly trained in the applicable survey techniques and training was documented.
- 5) MDC values and the assumptions used to develop them were appropriate for the instruments and the survey methods used to collect the data.
- 6) The survey methods used to collect the data were appropriate for the media and types of radiation being measured.
- 7) Special instrument methods used to collect data were applied as warranted by survey conditions, and were documented in accordance with an approved site Survey Request procedure.
- 8) The custody of samples that were sent for off-site analysis was tracked from the point of collection until final results were provided.
- 9) Final status survey data consists of qualified measurement results representative of current facility status and were collected in accordance with the applicable survey design package.
If a discrepancy existed where one or more criteria were not met, the discrepancy was reviewed and corrective action taken (as appropriate) in accordance with site procedures.
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Final Status Survey Report - Open Land Area 0L6 and OLI0 7.2 Survey Variations (Design, Survey Request, LTP) 7.2.1 OL10-2 Mounded Area Sampling The OL10-2 survey unit contains a mounded area that includes a significant portion of building debris and other miscellaneous discarded materials. The mounded area is at it's highest along the river and slopes downward toward the center of the site. The depth of this mound is at least three (3) meters in many locations and may be more in others. The sampling plan was to dig through and sample this mound until base native soil materials were encountered. This was done not only for FSS work, but also during scoping and characterization activities as well. However, in some locations the depth of the mounded materials was deeper than SNEC sampling equipment could reach. Nevertheless, additional samples seemed unwarranted since no significant finds of radiologically elevated materials were confirmed other than in one portion of 0L6, which is located on the top of the mounded area near the river bank (see Figure 2).
7.2.2 Less Than 1 Meter Sample Depths In OL10-1, several samples were taken at less than one (1) meter depths because of the presence of the Switch Yard grounding mat which limits sampling to less than sixteen (16) inches (more or less). See Table 5.
7.2.3 Deleted Sample Points In OL10-3, sample points fourteen (14) through sixteen (16) were not taken because of the danger of falling off the riverbank. Scanning was also limited in this area for the same reason. In addition, one sample location reached refusal at about 0.5 meters. See Table 8.
7.2.4 Scan Areas Around Class I Areas Scanned areas (grids) in the Class 2 OL10 survey units were chosen to contain and surround Class 1 areas whenever possible. Therefore, these areas were selected judgmentally.
7.3 Quality Control Measurements Repeat scan measurements and samples were performed and met the applicable acceptance criteria established in Section 4.6 of SNEC Procedure E900-IMP-4520.04 (Reference 9.11). Quality Control (QC) measurements are reported in each of the applicable Appendices (A-2 through A-5) and in the data tables of Section 6. All QC measurements are taken in accordance with the requirements of Reference 9.1 and 16
Final Status Survey Report - Open Land Area OL6 and OL10 applicable site procedures, which requires that at least 5% of all samples and scans be re-done. No discrepancies are reported and at least 5% or more of all samples and scan measurements were repeated with acceptable results.
7.4 Assessment Summary Statistical testing of the data does not need to be Derformed for this final status survey since the data clearly show that the survey unit(s) meet the site release criteria. These survey units clearly meet the criterion because of the following:
- 1. ED All measurements in these survey units are less than or equal to the DCGLW, or
- 2. El A background reference area was used, and the difference between the maximum survey unit measurement and the lowest background reference area measurement are less than or equal to the DCGL.
8.0 Final Status Survey Conclusions The FSS for the 0L6 and OL10 open land areas was performed in accordance with the SNEC LTP and site implementing procedures. Final status survey data were collected to meet and/or exceed the quantity and quality specified for these areas as prescribed by the applicable survey design. The survey data for each survey unit met the following conditions:
- 1.
The average residual radioactivity within the 0L6 and OL10 areas is less than the assigned DCGLw.
- 2.
Since all measurements were less than the DCGLw, no DCGLEMC criteria need be applied.
- 3.
No additional remediation was needed in these areas after FSS activities were complete to reduce levels of residual radioactivity below concentrations necessary to meet site DCGLw values.
These conditions satisfy the release criteria established in the SNEC LTP and the radiological criteria for unrestricted use given in 10 CFR 20.1402. Therefore, it is concluded that the SNEC 0L6/OL10 areas as described in this report are suitable for unrestricted release.
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Final Status Survey Report - Open Land Area OL6 and OL1 0 9.0 References 9.1 SNEC License Termination Plan 9.2 SNEC Calculation E900-05-027, 'OL6 and OL10 Open Land Area - Survey Design".
9.3 Code of Federal Regulations, 10 CFR 20.1402.
9.4 Code of Federal Regulations, 10 CFR 50.82(a)(1 1).
9.5 SNEC Facility Site Area Grid Map - Drawing Number SNECRM-020.
9.6 SNEC Facility Historical Site Assessment Report, March 2000.
9.7 COMPASS computer program, Version 1.0.0, Oak Ridge Institute for Science and Education.
9.8 SNEC Procedure E900-IMP-4500.59, 'Final Site Survey Planning and DQA" 9.9 NUREG-1507, "Minimum Detectable Concentrations with Typical Radiation Survey Instruments for Various Contaminants and Field Conditions".
9.10 Visual Sample Plan computer program, Version 3.0, Battelle Memorial Institute.
9.11 SNEC Procedure E900-IMP-4520.04, "Survey Methodology to Support SNEC License Termination" 9.12 SNEC Procedure E900-ADM-4500.60 "Final Status Survey Report".
9.13 NUREG 1575 "Multi-Agency Radiation Survey and Site Investigation Manual" (MARSSIM), revision 1 August 2000 18