ML063400425

Final Status Survey Final Report Phase IV

ML063400425
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	11/20/2006
From:	Newson C, Randall D, Sergent G Connecticut Yankee Atomic Power Co
To:	NRC/FSME
References
Download: ML063400425 (55)

Text

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Final Status Survey Final Report Phase IV Connecticut Yankee Atomic Power Company Haddam Neck Plant gESTOR Haddam, Connecticut November 2006

Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Report - Phase IV November 2006 Prepared By: Date: _/K__ 4_ _

Dale Randall - FSS Engineer Reviewed By: Date: //6 ,

Ge ergent - FSS Engineer Approved By: Date: ___

Clyde Newson -Technical Support Manager

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 TABLE OF CONTENTS 1.0 Introduction ........................................................................................................ 3 1.1 Executive Summary ....................................................................................... 3 1.2 Phased Submittal Approach ........................................................................... 7 2.0 FINAL STATUS SURVEY Program Overview ............................................... 11 2.1 Survey Planning ............................................................................................ 13 2.2 Survey Design .............................................................................................. 18 2.3 Survey Implementation ................................................................................ 21 2.4 Survey Data Assessment .............................................................................. 22 2.5 Quality Assurance and Quality Control Measures ........................................ 23 3.0 Site Information ................................................................................................ 26 3.1 Site Description ............................................................................................ 26 3.2 Survey Area/Unit Description ....................................................................... 27 3.3 Summary of Historical Radiological Data .................................................... 33 3.4 Conditions at the Time of Final Status Survey ............................................ 36 3.5 Identification of Potential Contaminants ..................................................... 37 3.6 Radiological Release Criteria ...................................................................... 37 4.0 Final Status Survey Protocol ........................................................................... 38 4.1 Data Quality Objectives ................................................................................ 38 4.2 Survey Unit Designation and Classification ................................................. 43 4.3 Background Determination ........................................................................... 43 4.4 Final Status Survey Plans .............................................................................. 43 4.5 Survey Design .............................................................................................. 44 4.6 Instrumentation ........................................................................................... 45 4.7 Survey Methodology ..................................................................................... 45 4.8 Quality Control Surveys ............................................................................... 46 5.0 Survey Findings ................................................................................................ 46 5.1 Survey Data Conversion ............................................................................. 47 5.2 Survey Data Verification and Validation ...................................................... 48 5.3 Evaluation of No. of Sample and Measurement Locations in SUs ............... 49 5.4 Comparison of Findings with Derived Concentration Guideline Levels .......... 50 5.5 USNRC/Independent Verification Team Findings ....................................... 50 6.0 Summary .......................................................................................................... 50 7.0 References ........................................................................................................ 50 8.0 Appendices ........................................................................................................ 53 I

Connecticut Vankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 LIST OF TABLES 1-1 Phase IV Survey Unit Classification and Description List ........................... 5 2-1 Derived Concentration Guideline Levels for Land Area FSS ........................ 15 2-2 HNP LTP Compliance Equation 5-1 values ............................................. 16 2-3 FSS Area Classifications .................................................................. 18 2-4 Easy-to-Detect (ETD) and Hard-to-Detect (HTD) Radionuclides .................. 19 4-1 Action Levels .............................................................................. . 41 4-2 Number of Surface Samples for FSS ................................................... 44 5-1 Summary of Statistical Analysis for Sediment Samples ............................ 48 LIST OF FIGURES 1-1 Phase IV Subm ittal ....................................................................... 6 1-2 FSS Final Report Phased Submittal Areas ............................................. 10 2-1 FSS Organizational Chart ................................................................ 13 2

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006

1.0 INTRODUCTION

1.1 Executive Summary The purpose of this Final Status Survey (FSS) Final Report is to provide a summary of the survey results and the overall conclusions, which demonstrate that the Connecticut Yankee Atomic Power Company's (CYAPCO's) Haddam Neck Plant (HNP) site, or portions of the site, meets established criteria for release for unrestricted use. The FSS results provided herein only address the dose component due to soil as provided in the HNP License Termination Plan (LTP) (Reference 7.1) compliance Equation 5-1. The remaining two components, present and future groundwater, were bounded on an individual survey unit basis as discussed in Integrated Site Closure (ISC) memo 06-024, "Initial Target Operational DCGLs for CY" (Reference 7.2).

This report also documents that the FSS activities were performed consistent with the guidance provided in the HNP LTP; NUREG-1575, "Multi-Agency Radiation Survey and Site Investigation Manual" (MARSSIM) (Reference 7.3); CYAPCO program document ISC-GQP-00001-003, "Final Status Survey Quality Assurance Plan" (Reference 7.4);

CYAPCO procedure GPP-GGGR-R5120-002, "Final Status Survey Program (RPM5.1-00)" (Reference 7.5); and, various station implementing procedures.

This FSS Final Report has been written consistent with the guidance provided in NUREG-1757, Vol. 2, "Consolidated NMSS Decommissioning Guidance-Characterization, Survey, and Determination of Radiological Criteria" (Reference 7.6); MARSSIM; and, the requirements specified in GPP-GGGR-R5122-001, "Preparation of Final Status Survey Reports (RPM 5.1-22)" (Reference 7.7).

To facilitate the data management process, as well as overall project management, FSS Final Reports will incorporate multiple Survey Unit Release Records. Survey Unit Release Records are complete and unambiguous records of the as-left radiological status of specific survey units. Sufficient data and information are provided in each Survey Unit Release Record to enable an independent re-creation and evaluation at some future time of both the survey activities and the derived results.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 This report contains a compilation of sixteen (16) Survey Unit Release Records that are within the Phase IV scope. The Phase IV FSS Final Report specifically addresses sixteen (16) water covered survey units and/or permanent wetland areas of the HNP site that total approximately 29.5 surface acres in size (119,425 in 2). Table 1-1 provides a listing of all survey units addressed in this report including the classification and general description for each. Figure 1-1 depicts the locations of the survey units in relation to the INP site, as well as, survey unit boundaries.

All Final Status Survey activities essential to data quality have been implemented and performed under approved procedures. Trained individuals, using appropriate sampling equipment and laboratory equipment that is sensitive to the suspected contaminants, performed the FSS of the Phase IV survey units. The survey data for all Phase IV survey units demonstrate that the dose from residual radioactivity in soil is less than the dose target set for the soil portion of the maximum annual dose criterion for license termination for unrestricted use specified in 10CFR20.1402 (see Table 2-1). The additional requirement of 10CFR20.1402 that all residual radioactivity be reduced to levels that are As Low As Reasonably Achievable (ALARA) has been satisfied.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 Table 1-1 Phase IV Surey Unit Classification and Description List Survey Survey Class General Description of the Survey Unit (

Area Unit 9106 0001 1 Discharge Canal, surface area (1,917m 2) 9106 0002 2 Discharge Canal, surface area (5,520 m2) 9106 0003 2 Discharge Canal, surface area (8,292M 2) 9106 0004 2 Discharge Canal, surface area (9,900 M2) 9106 0005 2 Discharge Canal, surface area (9,632 M2) 9106 0006 2 Discharge Canal, surface area (9,716 M2 )

9106 0007 2 Discharge Canal, surface area (8,692 M2) 9106 0008 2 Discharge Canal, surface area (9,763 Mi) 9106 0009 2 Discharge Canal, surface area (9,933 mi2 )

9106 0010 2 Discharge Canal, surface area (9,512 M2 )

9106 0011 2 Discharge Canal, surface area (6,394 m 2) 9106 0012 2 Discharge Canal, surface area (7,272 Mi) 9106 0013 2 Discharge Canal, surface area (9,011 M2) 9106 0014 1 Discharge Canal, surface area (1,870 M2) 9106 0015 1 Discharge Canal, surface area (1,170M 2) 9508 0000 3 North Pond, surface area (10,831m 2)

(1)Refer to Section 3.2 for a more detailed description 5

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Figure 1-1, Phase IV Submittal 6

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 1.2 Phased Submittal Approach To minimize the incorporation of redundant historical assessment and other FSS program information, and to facilitate potential phased releases from the current license, FSS Final Reports will be prepared and submitted in a phased approach. CYAPCO estimates that a total of seven (7) FSS Final Reports will be submitted during the decommissioning project (see Figure 1-2 for locations of phased submittal areas).

Phase I FSS Final Report On April 29, 2004, CYAPCO submitted a request to release a portion of the HNP site (Reference 7.8) from the 10CFR50 License (DPR-61).

Specifically, the request addressed the removal and release of the East Site Grounds (Survey Area 9532), a non-impacted area, from the Part 50 License. In accordance with Section 1.4.2 of the HNP LTP, and the USNRC Safety Evaluation dated November 25, 2002 (Reference 7.9),

CYAPCO determined the proposed action would have no adverse impact on the ability of the site in aggregate to meet 10CFR20, Subpart E, criteria for unrestricted release. The request did not contain a FSS Final Report for Survey Area 9532, because this area was classified as non-impacted.

The site release and removal of Survey Area 9532 from the site was approved by the USNRC on September 01, 2004 (Reference 7.10).

Phase II FSS Final Report On March 8, 2005, CYAPCO submitted a request to release a portion of the HNP site (Reference 7.11) from the 10CFR50 License (DPR-61).

Specifically, the request addressed the removal and release of the fourteen (14) surface survey units, and one (1) subsurface survey unit, which collectively made up the area defined as Phase II. In accordance with Section 1.4.2 of the HNP LTP, and the USNRC Safety Evaluation dated October 5, 2005 (Reference 7.12), CYAPCO determined the proposed action would have no adverse impact on the ability of the site in aggregate to meet 10CFR20, Subpart E, criteria for unrestricted release. The request contained an FSS Final Report covering all of the areas involved. The site release and removal of Phase II from the site was approved by the NRC on February 28, 2006 (Reference 7.13).

Phase III FSS Final Report On May 4, 2006, CYAPCO submitted the Phase III FSS Report (Reference 7.14). This submittal included the FSS release records for a total of seven (7) surface survey units. In response to verbal comments and communications with the NRC staff, four (4) survey unit release records were revised to further clarify specific technical issues. Revision 7

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report- PhaseIV November, 2006 1 of the Phase III report and the associated revised release records were submitted to the USNRC on September 9, 2006 (Reference 7.15).

Phases IV The subject of this report.

Phases V, VI and VII Final Reports As discussed above, CYAPCO anticipates at least three (3) additional FSS Final Report submittals. Below is a list of the remaining survey areas, grouped by phase, with the approximate submittal date. Details on the number, description and location of survey units within each survey area can be found in Chapter 2 of the HNP LTP.

The schedule and identity of survey areas included in each of the remaining submittals were developed based on a review of the demolition and Final Status Survey schedule, as well as in consideration of USNRC review requirements. The demolition schedule, including the cleanup of demolition debris to permit access for FSS, is dynamic and subject to continued refinement in logic, durations, and completion dates. It is CYAPCO's intent to maintain the basic submittal milestone schedule provided below. However, because of potential changes in the decommissioning schedule, it is possible that additional, interim submittals will be filed with the NRC with the goal of providing Survey Unit Release Records as soon as possible to support the agency's review, as well as CYAPCO's goals regarding the release of site lands from the license.

Phase V FSS Final Report Submittal scheduled for December 2006 (11 Release Records)

• 9520 Southwest Site Storage Area

• 9530 Central Peninsula Area

• 9805 Subsurface Soils Associated with Peninsula

• 9807 Subsurface Soils Associated with 9520 Phase VI FSS Final Report Submittal scheduled for February 2007 (15 Release Records)

• 9304 Southwest Protected Area Grounds

• 9504 Bypass Road and Secondary Parking Lot

• 9506 North Site Grounds (Non-Protected Area)

• 9512 Northwest Site Grounds (Non-Protected Area)

• 9522 Southeast Site Grounds (Non-Protected Area)

• 9539 ISFSI Haul Road

• 9804 Subsurface Soils Associated with 9522 8

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Phase VII FSS Final Report Submittal scheduled for May 2007 (19 Release Records)

• 9302 Northwest Protected Area Grounds

• 9306 South Central Protected Area Grounds

• 9312 Northeast Protected Area Grounds

• 9313 Central site Grounds

• 9514 Primary Parking Lot

• 9527 East Mountain Side

• 9801 Subsurface Soils in Radiologically Controlled Area

• 9802 Subsurface Soils Associated with 9308

• 9803 Subsurface Soils Located North of Industrial Area 9

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 10

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report- PhaseIV November, 2006 2.0 FINAL STATUS SURVEY PROGRAM OVERVIEW The FSS Program consists of the methods used in planning, designing, conducting, and evaluating FSS activities at the [NP site to demonstrate that the premises are suitable for release in accordance with the criteria for decommissioning in Title 10CFR20, Subpart E. The actual FSS serves as a key element to demonstrate that:

• Dose from residual radioactivity is less than the maximum annual dose criterion for license termination for unrestricted use as specified in Title 10CFR20.1402 - that is, the residual radioactivity that is distinguishable from background radiation results in a Total Effective Dose Equivalent (TEDE) to an average member of a critical group that does not exceed twenty five (25) millirem per year (25 mrem/yr); and,

" All residual radioactivity at the site is reduced to levels that are As Low as Reasonably Achievable (ALARA) in accordance with Title 10CFR20.1402.

To implement the FSS Program as provided in Reference 7.5, and MARSSIM, CYAPCO established an organization within the Site Closure Group with sufficient management and technical resources to fulfill project objectives and goals. The FSS organization was responsible for the safe completion of all activities related to FSS necessary to obtain the radiological release for unrestricted use of the HNP site. Approved site procedures directed this process to ensure consistent implementation and adherence to applicable requirements.

Figure 2-1 provides an organizational chart of the FSS organization and its relationship within the Project Support Directorate.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Figure 2-1 FSS Organizational Chart Di*rector of1 Project Support RP/ FSS Manager [

Ground Water [RCRA E Technical Support FSS Project Lead Group Manager FSS Engineers FSS Supervisors I Ph FSS Technicians I Integrated Site Closure Group

---

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 2.1 Survey Planning After termination of commercial operations, the initial development and planning phase started in 1997 with the characterization and Historical Site Assessment (HSA) processes that continued until submittal of the License Termination Plan in 2000. The HSA consisted of a review of site historical records regarding plant incidents, radiological survey documents, operations and maintenance records, plant modification documents, and both routine and special reports submitted by CYAPCO to various regulatory agencies. Along with the HSA, interviews with site personnel, both past and present, reviews of historical site photos and extensive area inspections were performed to meet the following objectives:

• To develop the information to support FSS design including the development of Data Quality Objectives (DQOs) and survey instrument performance standards;

• To develop the initial radiological information to support decommissioning planning including building decontamination, demolition, and waste disposal;

• To identify any unique radiological or health and safety issues associated with decommissioning;

• To identify the potential and known sources of radioactive contamination in systems, on structures, in surface or subsurface soils, and in ground water;

• To divide the HNP site into manageable areas or units for survey and classification purposes; and,

" To determine the initial classification of each survey area or unit as non-impacted or impacted Class 1, 2, or 3 as defined in MARSSIM or Class A, B, or C for subsurface soils (below 15 cm) as described in the HNP LTP.

DQOs developed and implemented during the initial phase of planning directed all data collection efforts. The DQOs are qualitative and quantitative statements derived from the DQO process that clarify technical and quality objectives, define the appropriate type of data, and specify tolerable levels of potential decision errors used as the basis for establishing the quality and quantity of data needed to support decisions.

This process, described in MARSSIM, and procedure GGGR-R5111-002, "Preparation of Final Status Survey Plans (RPM 5.1-11)" (Reference 7.16), is a series of graded, planning steps found to be effective in establishing criteria for data quality and developing survey plans.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Used extensively during FSS, the DQO approach consists of the following seven steps:

• State the Problem-

• Identify the Decision-

• Identify the Inputs to the Decision-

• Define the Boundaries of the Decision-

• Develop a Decision Rule-

• Specify Tolerable Limits on Decision Errors-

• Optimize the Design for Obtaining Data-A fundamental precursor to survey design is to establish a relationship between the release criteria and some measurable quantity. This is done through the development of Derived Concentration Guideline Values (DCGLs). The DCGLs represent average levels of radioactivity, above background levels, presented in terms of surface or mass activity concentrations. Chapter 6 of the HNP LTP describes in detail the modeling used to develop the DCGLs for soil (called Base Case Soil DCGL), existing groundwater radioactivity, and future groundwater radioactivity from building basements and footings.

A reduction to the Base Case Soil DCGLs provided in Chapter 6 of the HNP LTP must be performed to ensure compliance with the release criteria of twenty five (25) mrem/yr TEDE when all three pathways (soil, existing groundwater and future groundwater) are potentially present.

Chapter 5 of the HNP LTP shows a compliance formula, Equation 5-1, for including the total dose from the three pathways. The reduced quantity becomes the Operational DCGL, whose relationship to the Base Case Soil DCGL is shown by Equation 5-2 of the HNP LTP. Table 2-1 provides a listing of the Base Case and required MDC values.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Yankee Atomic Power Company Connecticut Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Table 2-1 Derived Concentration Guideline Levels for Soil Base Case Soil Required MDC (pCilg)

Radionuclide DCGL (pCi/g) RequiredMDC_(pi/g (25 mrem/yr) (1.0 mrem/yr)

H-3 412.00 16.50 C-14 5.66 0.23 Mn-54 17.40 0.70 Fe-55 27400.00 1100.00 Co-60 3.81 0.15 Ni-63 723.00 28.90 Sr-90 1.55 0.06 Nb-94 7.12 0.29 Tc-99 12.60 0.50 Ag-108m 7.14 0.29 Cs-134 4.67 0.19 Cs-137 7.91 0.32 Eu-152 10.10 0.40 Eu-154 9.29 0.37 Eu-155 392.00 15.70 Pu-238 29.60 1.18 Pu-239/240 26.70 1.07 Pu-241 870.00 34.80 Am-241 25.80 1.03 Cm-243/244 29.00 1.16 The compliance equation of the HNP LTP Equation 5-1, equates the total dose to three (3) components, soil dose, existing groundwater dose and future groundwater dose. This report contains only the results of the FSS that addresses the dose due to soil. To calculate DCGLs, dose models were developed to relate levels of residual radioactivity to potential dose. In the HNP LTP, Equation 5-1 expresses the total dose (HiTotal) from all three (3) media, which is shown below:

Hrotat can be expressed as:

HTotal = HSOl + HExistingGW + HFutureGW (HNP LTP Equation 5-1)

The total dose, HT,-or, under the LTP criteria is twenty five (25) mrem/yr TEDE from all three (3) components. The allowable total dose under the Connecticut Department of Environmental Protection (CTDEP) radiological remediation standard for Connecticut Yankee (CY) is nineteen (19) mrem/yr TEDE.

Therefore, the value for HTa-o is effectively nineteen (19) mrem/yr for all survey units. To determine the Hsoil (the dose equivalent for the Operational DCGLs) 15

Connecticut Yankee Atomic Power Company Haddam Neck Plant Yankee Atomic Power Company Connecticut iladdam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 one must subtract the existing and future groundwater dose values as shown below.

HSOi, =

1

'Tofal - H~xis~ing Gw -HFutIreGWV (Operational DCGL equivalent)

The present and future groundwater terms were bounded on an individual survey unit basis as discussed in Integrated Site Clouse (ISC) memo 06-024, "Revised Target Operational DCGLs/Dose Targets for CY" (Reference 7.2). Table 2-2 summarizes the 14NP Equation 5-i values for each of the Survey units discussed in this report. Table 2-2 also shows the maximum allowable existing groundwater dose that can exist at the time of NRC license termination.

Table 2-2 HNP LTP Compliance Equation 5-1 values Existing Future Ground Soil Dose Survey Ground Water Water Dose Allowable Soil (Operational Unit (bounding Dose*2 ) DCGL (bounding Value)) ()

V Equivalent) ()

Value))

9106-0001 2 0 17 4.10 9106-0002 2 0 17 1.92 9106-0003 2 0 17 3.15 9106-0004 2 0 17 5.10 9106-0005 2 0 17 1.97 9106-0006 0 0 19 3.14 9106-0007 0 0 19 2.49 9106-0008 0 0 19 2.15 9106-0009 0 0 19 3.04 9106-0010 0 0 19 1.12 9106-0011 0 0 19 1.96 9106-0012 0 0 19 0.13 9106-0013 0 0 19 0.11 9106-0014 2 0 17 3.55 9106-0015 0 0 19 3.12 9508-0000 0 0 19 0.40 (1) These values were taken from ISC memo 06-024, "Initial Target Operational DCGLs for CY" (Reference 7.2). The maximum allowable groundwater dose to meet the USNRC limit of 25 mrem/yr is 8 mrem/yr or 6 mrem/yr for Survey Units with soil dose limits of 17 and 19 mrem/yr respectively.

(2) The release criteria for unrestricted use of the HNP LTP is targeted to 25 mrem/yr plus ALARA.

(3) The release criteria for unrestricted use as agreed to with the CTDEP is to be 19 mrem/yr plus ALARA.

The development of information to support decommissioning planning and execution was accomplished through a review of all known site radiological and environmental records. Much of this information was 16

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 consolidated in the "Results of Scoping Surveys" (Reference 7.17);

"Augmented Characterization Survey Report" (Reference 7.18);

"Characterization Report" (Reference 7.19); "Historical Site Assessment Supplement (HSA)" (Reference 7.20); and, in files containing copies of records maintained pursuant to Title 10CFR 50.75(g)(1). These documents are discussed further in applicable sections of this report.

An initial objective of site characterization and HSA was to correlate the impact of a radiological event to physical locations on the plant site and to provide a means to correlate subsequent survey data. To satisfy these objectives, the FSS organization divided the site into large, manageable areas and assigned a unique four digit System Survey Code (e.g. Survey Area 9528) to each area. The area designations form the basis for survey units presented in Table 1-1 of this report. Physically, survey area boundaries made use of logical physical boundaries and site landmarks (paved roads, fences, stone walls) or were determined through the integration of global positioning system (GPS) equipment with commercially available mapping software using coordinates consistent with the Connecticut State Plane System, North American Datum (NAD) 1927.

Upon completion of survey area assignment, the FSS organization began the task of initial classification and establishing the initial set of survey units. Classification, as described in MARSSIM, is the process by which an area or survey unit is described according to its radiological characteristics and potential for residual radioactivity. Not all areas of the site had the same potential for residual radioactivity. Residual radioactivity could be evenly distributed over a large area, appear as small areas of elevated activity or a combination of both. In some cases, there may be no residual radioactivity in a survey unit. Therefore, the adequacy and effectiveness of the FSS process depends upon properly classified survey units to ensure that areas with the highest potential for contamination receive a higher degree of survey effort.

A survey area may consist of one or more survey units. A survey unit is a physical area consisting of structures or land areas of a specified size and shape that would be subjected to a final status survey. Survey units were limited in size based on classification, exposure pathway modeling assumptions, and site-specific conditions. Utilization of this method of classification and size limitation ensures that each area was assigned an adequate number of data points. The surface area limits provided in MARSSIM were used to establish the initial set of survey units for the HNP LTP. For identification, survey units were assigned the area four-digit code and a sub-code to designate the unit within the survey area (e.g.

Survey Unit 9528-0002). Table 2-3 provides an outline for classification and area limits.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 Table 2-3 FSS Area Classifications Survey Unit Surface Area Limit Contamination Classification Potential Structures:

Class I (floor area) Up to 100 m2 Land Area: Up to 2,000 m2 Highest Class A Subsurface: No limit Structures: 100 M2 to 1,000 M2 Class 2 (floor area) M to 1,000 M2 Moderate Land Area: 2,000 m to 10,000 m Class B Subsurface: No limit Structures:

Class 3 (floor area) No limit Lowest Land Area:

Class C Subsurface I Several survey units have undergone reclassification prior to FSS.

Verification and change to increase the class (more restrictive) can be performed at anytime prior to FSS. New sample results or emergent data may require evaluation and reclassification to more restrictive criteria.

Final classification was performed in conjunction with the preparation of the FSS plan, thus indicating all issues of classification are resolved.

2.2 Survey Design Final status surveys for the HNP surface soils and structures are designed following HNP procedures, Section 5 of the HNP LTP and MARSSIM guidance using an integrated approach using combinations of fixed measurements, traditional scanning surveys, and other advanced survey methods, as appropriate, to evaluate survey units relative to their applicable release criteria.

During characterization and in preparation for FSS, the HNP Radiochemistry Lab, using gamma spectroscopy, analyzed soil samples collected from random and biased locations in selected survey units for Easy-to-Detect (ETD) radionuclides (Table 2-4). Gamma spectroscopy indicated that Cs-137 and/or Co-60 would be the primary radionuclides of concern for survey design and FSS for a majority of the areas submitted in this report. Applied statistically, these data were used to determine the number of samples required to achieve adequate sample design.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Yankee Atomic Power Company Connecticut iladdam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Another important facet of the DQO process is to identify the radionuclides of concern and determine the concentration variability.

Characterization included analyses for Hard to Detect (HTD) radionuclides. Although the HNP LTP only required a minimum of 5%,

typically 10% of the soil samples, and in some cases a higher percentage, were sent to the offsite laboratory for HTD analysis. Strontium-90 was the most prevalent HTD radionuclide identified in samples.

Most radionuclides could be screened out or excluded from the survey design under HNP LTP Section 5.4.7.2. Radionuclide screening or de-selection is a process where an individual radionuclide or aggregate may be considered insignificant and eliminated from the FSS. The criteria for de-selection are concentrations less than 5% for individual radionuclides and less than 10% for aggregates. Exceptions to this are discussed in applicable sections of this FSS Final Report and associated Survey Unit Release Records. Consistent with Equation 5-7 of the HNP LTP, the 5%

rule for single radionuclides or 10% rule for multiple radionuclides is conservative relative to the process presented in Title 10CFR20 in which radionuclides that contribute less than 10% to dose, and where the aggregate does not exceed 30%, are not required to be included in dose assessment.

Table 2-4 Easy-to-Detect (E D) and Hard-to-Detect (HTD) Radionuclides Radionuclide Type When Analyzed Analysis H-3 HTD AS NEEDED Liquid Scintillation C- 14 HTD AS NEEDED Liquid Scintillation Mn-54 ETD ALWAYS Gamma Spectroscopy Fe-55 HTD AS NEEDED Liquid Scintillation Co-60 ETD ALWAYS Gamma Spectroscopy Ag-108m ETD ALWAYS Gamma Spectroscopy Ni-63 HTD AS NEEDED Liquid Scintillation Sr-90 HTD AS NEEDED Liquid Scintillation Nb-94 ETD ALWAYS Gamma Spectroscopy Tc-99 HTD AS NEEDED Liquid Scintillation Cs-134 ETD ALWAYS Gamma Spectroscopy Cs-137 ETD ALWAYS Gamma Spectroscopy Eu-152 ETD ALWAYS Gamma Spectroscopy Eu-154 ETD ALWAYS Gamma Spectroscopy Eu-155 ETD ALWAYS Gamma Spectroscopy Pu-238 HTD AS NEEDED Alpha Spectroscopy Pu-239/240 HTD AS NEEDED Alpha Spectroscopy Pu-241 HTD AS NEEDED Liquid Scintillation Am-241 ETD ALWAYS Gamma Spectroscopy HTD Alpha Spectroscopy Cm-243/244 HTD AS NEEDED Alpha Spectroscopy 19

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 As described in detail in the LTP, the dose model applied to the discharge canal presumes that the canal sediments are dredged to a depth of three (3) feet and are spread for the planting of crops per the Resident Farmer Scenario. Consequently, the soil DCGLs are directly applied to the canal sediment media which are sampled by coring to a nominal depth of three (3) feet.

Sediment sample locations were determined randomly for Class 3 survey units, or by a triangular systematic grid with a random starting point for Class I and 2 survey units using commercially available software.

Using GPS coordinates, sample measurement locations were identified in North American Datum (NAD) 1927 coordinates that were supplied to the sampling vendor, Ocean Surveys, Inc. (OSI) of Old Saybrook, Connecticut. Discharge Canal sampling was accomplished using direct push technology to collect composite samples of bottom and average high water mark sediments. Sediment cores from the Discharge Canal were obtained by OSI using a vibrating corer that is platform mounted on a sampling vessel. The core barrel was a three (3) inch diameter thin-walled aluminum tube which also serves as a core liner (ten (10) feet or less). A core catcher was available to prevent the sample from sliding out of the bottom of the tube. Vessel positioning and the determination of sample locations were accomplished using a GPS interfaced with a navigation and data logging system. The FSS plan provided a map and GPS positions to Ocean Surveys, Inc. for the as-desired locations for core borings.

After extraction, water was drained from above the sample by drilling holes above the sediment. The liner was cut, capped, sealed, labeled and turned over from the Ocean Surveys, Inc. to site personnel who processed and controlled the samples under COC requirements. Rinsing of the barrel and associated equipment was performed between sampling events. New aluminum tubes were used for each sample to prevent cross-contamination of subsequent samples.

In each survey unit, a minimum of five (5) percent of the samples were collected for quality control analysis such as "splits" or duplicates. Most survey units exceeded this requirement by a significant margin. In general, the sample tubes provided more than enough aliquot to accommodate split sampling.

Offsite laboratories were chosen to perform ETD and HTD analysis of samples collected during FSS. Laboratory analysis results were reported as actual calculated results. Results reported as <MDC (i.e., less than minimum detectable concentration) were not accepted for FSS. Sample report summaries included unique sample identification, analytical 20

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 method, radioisotope, result and uncertainty of two standard deviations, laboratory data qualifiers, units and required MDC.

A consideration of survey design was the use of "surrogates." In lieu of analyzing every sample for HTDs, the development and application of surrogate ratio DCGLs is an accepted industry practice to assay HTD radionuclides. Surrogate ratios allow for expedient decision making in characterization, remediation planning or FSS design.

Briefly described, a surrogate is a mathematical ratio where an ETD radionuclide concentration is related to a HTD radionuclide concentration, such as Cs-137 to Sr-90. From the analytical data, a ratio is developed and applied in the survey scheme for samples taken in the area. The result is referred to as the surrogate DCGL. Details and applications of this method are provided in Section 5.4.7.3 of the HNP LTP. Surrogates were not required for the survey areas covered by this FSS Final Report.

Some portion of the Cs-137 and Sr-90 found in the soil samples is certainly attributed to "background" or fallout; however, the DQO process assessed the application of media specific radiation background and ambient area radiation background to specific survey areas and units.

Based upon the DQO process, the FSS planning determined that background subtraction would not be applied during the survey of the land areas included in this submittal.

2.3 Survey Implementation Started in November 2001, FSS plans were developed to guide the physical work of FSS implementation for each survey unit. Some of the tasks included in the implementation were:

• Verification and validation of personnel training as required by procedure GPP-GGGR-R5400-000 "Site Closure Training Program (RPM 5.4-0)" (Reference 7.21);

• Implementation of a work control process including applicable health and safety procedures under GGGC-00001-004, "Work Plan and Inspection Record" (Reference 7.22);

" Determination of the amount of samples required to meet survey DQOs as described in GGGR-R5112-001, "Determination of the Number Samples for Final Status Survey (RPM 5.1-12)" (Reference 7.23);

" Determination of the overall survey design and objectives including where measurements or samples are to be made or collected, generation of detailed maps of the survey area showing the 21

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 measurement and sample locations, and investigation levels and corrective actions under procedure RPM 5.1-11 (Reference 7.16);

" Maintaining Quality Assurance and Quality Control requirements (e.g., replicate measurements or samples) in accordance with procedure GPP-GGGR-R5124-000, "Split Sample Assessment for Final Status Survey (RPM 5.1-24)" (Reference 7.24) and the FSSQAP;

" Providing accountability and sample integrity for sample submission to approved laboratories as provided in procedure GPP-GGGR-R5104-003, "Chain of Custody for Final Status Survey Samples (RPM 5.1-5)"

(Reference 7.25); and,

• Application of the Operational DCGLs in conjunction with the unity rule, when applicable, to sample results in accordance with the Data Quality Assessment (DQA) process as detailed in procedure GGGR-R123-000, "Data Quality Assessment (RPM 5.1-23)" (Reference 7.26).

The FSS implementation and completion process resulted in the generation of field logs, and radionuclide specific analysis. Data were stored electronically on the CYAPCO network server.

2.4 Survey Data Assessment Prior to proceeding with data evaluation and assessment, the assigned FSS Engineer resolves and documents discrepancies between the data quality or the data collection process and the applicable requirements.

The DQA process is an evaluation method used during the assessment phase of FSS to ensure the validity of FSS results and demonstrate achievement of the survey plan objectives. The first step in the data assessment process converts all of the survey results to DCGL units. The individual measurements and sample concentrations are compared to the Operational DCGL in conjunction with the unity rule, when applicable, for evidence of small areas of elevated activity or results that are statistical outliers relative to the rest of the measurements. When practical, graphical analyses of survey data that depicts the spatial correlation of the measurements were used.

To demonstrate that survey data fulfills the radiological release criteria, FSS planning incorporated hypothesis testing and probabilistic sampling distributions to control decision errors during data analysis. Hypothesis testing is a process based on the scientific method that compares a baseline condition to an alternate condition. The baseline condition is technically known as the null hypothesis. Hypothesis testing rests on the premise that the null hypothesis is true and that sufficient evidence must be provided for rejection. In designing the survey plan, the underlying assumption, or 22

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 null hypothesis was that residual activity in the survey unit exceeded the release criteria. Rejection of the null hypothesis would demonstrate that residual activity was at or below the release criteria objective of the FSS.

Hypothesis testing was performed by applying the Sign Test on the sample data associated with the survey unit. The Sign Test is considered a one-sample statistical test that compares sample data directly to the release criteria. Combined with an effective sampling scheme, passing the Sign Test constitutes satisfying the release criteria. Selection of the Sign Test is prudent and conservative in the assumption that the radionuclides being considered are not present in background or are at levels at a small fraction of the applicable release criteria. Reference areas and reference samples are not needed, thus simplifying the FSS. Furthermore, any background contribution (e.g., Cs-137 from atmospheric weapons testing) in the sample increases the likelihood of failing the survey unit, or requiring investigation, which is conservative. If the release criteria were exceeded, or if results indicated the need for additional data points, appropriate further actions were implemented usually through the issue of an addendum to the FSS plan.

Probabilistic sampling was the preferred method to select a sample so that each item in the population being studied had a known likelihood of being included in the sample. Probabilistic sampling included simple random sampling, where every sample had the same chance of being included, or systematic random sampling, where samples were arranged in order and a random starting point was selected.

2.5 Quality Assurance and Quality Control Measures Quality assurance and control measures were employed throughout the Final Status Survey process to ensure that all decisions were based on data of acceptable quality. Quality assurance and control measures were applied to ensure:

• The plan was correctly implemented as prescribed;

• DQOs were properly defined and derived;

• All data and samples were collected by individuals with the proper training following approved procedures;

• All collected data were validated, recorded, and stored in accordance with approved procedures;

• All required documents were properly maintained; and,

• Corrective actions were prescribed, implemented and tracked as necessary.

23

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 The off-site laboratories used for analysis of the samples collected during FSS maintain Quality Assurance Plans designed for their facility.

CYAPCO reviews these plans, as required by the "Quality Assurance Program for the Haddam Neck Plant (CYQAP)," (Reference 7.27) and the FSSQAP, prior to selection of a laboratory for FSS sample analysis to ensure standards are acceptable. The on-site laboratory was not used to analyze FSS samples used for non-parametric statistical sampling.

The Site Closure organization maintains a formal, stand alone training program for FSS technicians and FSS Supervision. The training program relates to, but is independent of, the Health Physics Department training program. All FSS technicians met the requirements of the American National Standards Institute, ANSI N18.1-1971, "Selection and Training of Nuclear Plant Personnel", or were junior technicians working under the direct supervision of an ANSIN18.1-1971 qualified Technician and/or FSS supervision. Supervisory and technical support personnel had sufficient education, experience and certification to qualify personnel and perform assigned duties. Some lead Site Closure personnel have had additional training in MARSSIM implementation; and some were certified by the American Board of Health Physics.

The Site Closure Group has established a Curriculum Advisory Committee (CAC) - a training committee - that is comprised of Site Closure Management, a Training Coordinator and Site Closure lead personnel. The CAC is responsible for department training implementation, including review and approval of new training such as required reading (knowledge measures) and On-the-Job (OJT) training and Task Qualification Records (performance measures), revision of existing training, and designation of personnel as OJT Trainers, Evaluators and Subject Matter Experts. The objective of the CAC is to establish effective training and qualifications programs and ensure the appropriate design, development and implementation of the Site Closure training program.

During 2006, one (1) Quality Surveillance Report (QSR) was produced on activities related to FSS. In general, these reports were performed to evaluate the adequacy of the implementation of regulatory and HNP LTP and FSS requirements.

QSR-06-01-CY (Reference 7.28) performed during January of 2006, concluded that a sampling of the Survey Unit Release Records to be submitted in Phase III met the HNP LTP and FSS programmatic requirements.

During 2006, one (1) Quality Assurance Audit was performed covering activities specific to the FSS/CY LTP. The purpose of the audit and associated surveillances was to verify that the licensee was appropriately implementing the programs, processes and procedures which satisfy the 24

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 requirements of the License Termination Plan and associated regulatory requirements.

AUDIT CY-06-A05-01 (Reference 7.29) performed during May of 2006 covered FSS activities including a sampling of the implementation of FSS activities covered in Release Records to be submitted in Phase IV. The audit concluded that all areas examined met applicable requirements and were satisfactory.

As of early November, the Integrated Site Closure has performed three Self Assessments for 2006. As required by the FSSQAP (Reference 7.4)

Self Assessments are performed on a periodic basis to ensure that the FSS program conforms to the requirements of the LTP and implementing procedures.

SCA-06-01 (Reference 7.30), performed in April 2006, was performed as a follow-up to Condition Report (CR)05-781 (Reference 7.31). The issues identified involved soil sample collection, particularly samples used for quality control. The Self Assessment provided recommendations for improvement.

SCA-06-02 (Reference 7.32) performed in August, 2006, noted that personnel and staffing changes had been implemented since major FSS field activities were last performed. In anticipation of an increase in FSS field activities going forward, the Self Assessment sought to determine what lessons could be learned from recent FSS field activities, identify and correct deficiencies and further ensure Site Closure readiness for FSS.

SCA-06-03 (Reference 7.33) performed in November, 2006, was performed as an investigation of the cause of Condition Report (CR) 06-0223 (Reference 7.34). The CR identified an issue with split sample agreement. The Self Assessment observed that media homogenization for samples from the pond and discharge canal was made more difficult due to the large and varying quantities of clay to fine grained media collected from coring at these locations. In addition, moisture content, aliquot size and varying organic content further hampered the sample homogenization efforts. Recommendations for improvement included improving the briefing process with regards to split sample processing and employing the use of a mechanical sieve. The recommendations for improvement were implemented as of November 2006.

All findings from the QSRs, audits and assessments were corrected and systematic controls implemented as of the publication date of this report.

25

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 3.0 SITE INFORMATION 3.1 Site Description Haddam Neck Plant, owned by Connecticut Yankee Atomic Power Company, is located on the east bank of the Connecticut River, approximately twenty-one (21) miles south-southeast of Hartford.

The site consists of approximately five hundred twenty five (525) acres, with a minimum distance overland from the reactor containment to the site boundary of one thousand seven hundred and forty feet (1,740 ft), and the distance to the nearest residence is over two thousand feet (2,000 ft).

The plant incorporated a 4-loop closed-cycle pressurized water type Nuclear Steam Supply System (NSSS); a turbine generator and electrical systems; engineered safety features; radioactive waste systems; fuel handling systems; instrumentation and control systems; the necessary auxiliaries; and structures to house plant systems and other onsite facilities. HNP was designed to produce 1,825 MW of thermal power and 590 MW of gross electrical power.

Westinghouse Electric Corporation was responsible for design and fabrication of all nuclear steam supply and auxiliary systems and equipment, as well as design and supply of all secondary plant mechanical and electrical equipment, which it normally manufactures. Stone and Webster Engineering Corporation were responsible for site development, design of buildings and secondary systems, and all plant construction.

Each of these contractors was responsible to CYAPCO for tasks performed in their respective areas of design and construction. Pre-operational plant checkout, core loading, plant start-up and operation were the responsibility of CYAPCO.

On December 4, 1996, HNP permanently shut down after approximately 28 years of operation. On December 5, 1996, CYAPCO notified the USNRC of the permanent cessation of operations at the HNP site and the permanent removal of all fuel assemblies from the Reactor Pressure Vessel and their placement in the Spent Fuel Pool. Following the cessation of operations, CYAPCO began the decommissioning of the HNP site. The Post Shutdown Decommissioning Activities Report (PSDAR)

(Reference 7.35) was submitted, in accordance with Title 10CFR50.82 (a)(4), on August 22, 1997, and was accepted by the NRC. On January 26, 1998, CYAPCO transmitted an Updated Final Safety Analysis Report (UFSAR) (Reference 7.36) to reflect the plant's permanent shutdown status, and on June 30, 1998, the NRC amended the HNP Facility Operating License to reflect the plant condition. On October 19, 1999, the 26

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - Phase IV November, 2006 HNP Facility Operating License was amended to reflect the decommissioning status of the plant and long-term storage of the spent fuel in the spent fuel pool. Additional licensing basis documents were also revised and submitted to reflect long-term fuel storage in the spent fuel pool (Defueled Emergency Plan, Security Plan, QA program, and Operator Training Program).

In 1997, in accordance with NUREG/CR-5849 (Reference 7.37) initial site characterization was implemented. In 1999, following the guidelines of MARSSIM, initial characterization was completed. The information developed during the initial HNP characterization program represented a radiological assessment based on the knowledge and information available at the end of 1999.

3.2 Survey Area/Unit Description The following information is a description of each survey unit at the time of FSS from May through August 2006 (additional detail is provided in the Survey Unit Release Records). During this period, the approximately thirty (30) acres of water covered or permanent wetland areas of the Haddam Neck Plant site received a FSS. The Survey Units are water covered areas with sediment and/or other base materials making up the bottom.

As described in detail in the LTP, the dose model applied to the Phase IV survey areas presumes that sediments are dredged to a depth of three (3) feet and spread for the planting of crops per the Resident Farmer Scenario.

Consequently, the soil DCGLs are directly applied to the canal sediment media which are sampled by coring to a nominal depth of three (3) feet.

The FINP site maintains a reference coordinate system based on GPS coordinates using coordinates consistent with the Connecticut State Plane System. A benchmark was established as an origin for documenting survey efforts and results. The benchmark, an accessible iron pin located in the main parking lot, was established during the setup and calibration of the base station for the GPS receiver. The benchmark is also provided on Figure 1 of the attached Release Records to this FSS Final Report.

Survey Unit 9106-0001 Survey Unit 9106-0001 (Discharge Canal) was designated as Final Status Survey (FSS) Class 1 because its characterization data indicated that some samples may exceed the Operational DCGL. It consists of approximately 1,917 m2 (0.47 acres) of water covered sediment in an area located approximately 0.16 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately 27

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 communicates with the Connecticut River. The survey unit is bounded as follows: Survey Area 9522 is to the north and east (called north as orientated with the north to south flow of the Connecticut River); Survey Area 9520 is to the north and west, Discharge Canal Survey Unit 9106-0014 is to the south. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0002 Survey Unit 9106-0002 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 5520 m2 ( 1.36 acres) of water covered sediment in an area located approximately 0.20 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0014 is to the north, (called north as orientated with the north to south flow of the Connecticut River), Survey Unit 9521 is to the east, Discharge Canal survey unit 9106-0003 is to the south and Survey Area 9520 is to the west. The Survey Unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0003 Survey Unit 9106-0003 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 8,292 m2 ( 2.05 acres) of water covered sediment in an area located approximately 0.28 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. With "called north" oriented with the north to south flow of the Connecticut River, the survey unit is bounded as follows:

Discharge Canal survey unit 9106-0002 is to the north, Survey Area 9521 is to the east, Discharge Canal Survey Unit 9106-0004 is to the south and land surface area 9520 is to the west. The survey unit comprises the canal sediments to the deeper of three (3) feet or to the original construction depth. It extends up the canal banks to the mean high water level.

Survey Unit 9106-0004 Survey Unit 9106-0004 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,900 m2 (2.45 acres) of water covered sediment in an area located approximately 0.28 miles 28

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0003 is to the north, land surface area survey unit 9521 is to the east, Discharge Canal Survey Unit 9106-0005 is to the south and Survey Area 9520 is to the west. The survey unit comprises the canal sediments to the deeper of three (3) feet or the to original construction depth. It extends up the canal banks to the mean high water level.

Survey Unit 9106-0005 Survey Unit 9106-0005 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,632 m2 (2.38 acres) of water covered sediment in an area located approximately 0.55 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0004 is to the north (called north as orientated with the north to south flow of the Connecticut River), Survey Area 9521 is to the east, Discharge Canal Survey Unit 9106-0006 is to the south and Survey Area 9530 is to the west. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0006 Survey Unit 9106-0006 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,716 m2 (2.40 acres) of water covered sediment in an area located approximately 0.68 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0005 is to the north (called north as orientated with the north to south flow of the Connecticut River), land surface area survey unit 9521 is to the east, Discharge Canal Survey Unit 9106-0007 is to the south and Survey Area 9106-0012 (formerly a part of 9530) is to the west. The survey unit comprises the canal sediments to the deeper of three (3) feet or to the original construction depth and it extends up the canal banks to the mean high water level.

29

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 Survey Unit 9106-0007 Survey Unit 9106-0007 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 8,692 m2 (2.44 acres) of water covered sediment in an area located approximately 0.77 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit surrounds Survey Unit 9106-0015 and is also bounded as follows: Discharge Canal Survey Unit 9106-0006 is to the north (called north as orientated with the north to south flow of the Connecticut River), Survey Area 9521 is to the east, Discharge Canal Survey Unit 9106-0008 is to the south and Discharge Canal Survey Unit 9106-0013 (formerly a part of 9530) is to the west. The survey unit comprises the canal sediments to the deeper of three (3) feet or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0008 Survey Unit 9106-0008 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,763 m2 (2.41 acres) of water covered sediment in an area located approximately 0.92 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0007 is to the north (called north as orientated with the north to south flow of the Connecticut River), Survey Area 9523 is to the east, Discharge Canal Survey Unit 9106-0009 is to the south and Survey Area 9531 is to the west. The survey unit comprises the canal sediments to the deeper of three (3) feet or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0009 Survey Unit 9106-0009 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,933 m 2 (2.45 acres) of water covered sediment in an area located approximately 1.02 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0008 is to the north (called north as orientated with the north to south flow of the Connecticut River), land surface area 9523 is to the east, Discharge Canal Survey Unit 9106-0010 is to the south 30

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 and Survey Area 9531 is to the west. The survey unit comprises the canal sediments to the deeper of three (3) feet or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0010 Survey Unit 9106-0010 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,512 m 2 (2.35 acres) of water covered sediment in an area located approximately 1.10 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0009 is to the north (called north as orientated with the north to south flow of the Connecticut River), Survey Area 9523 is to the east, Discharge Canal Survey Unit 9106-0011 is to the south and Survey Area 9531 is to the west. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0011 Survey Unit 9106-0011 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 6,394 m (1.58 acres) of water covered sediment in an area located approximately 1.58 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Discharge Canal Survey Unit 9106-0010 is to the north (called north as oriented with the north to south flow of the Connecticut River), Survey Area 9521 is to the east, the Connecticut River is to the south and west, and Survey Area 9530 is also to the west. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0012 Survey Unit 9106-0012 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 7,272 m2 (1.80 acres) of water covered sediment in an area located approximately 0.73 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. This survey unit comprises the northern portion of the permanent wetland area. The survey unit is bounded as follows: Survey 31

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 Area 9530 is to the north and west (called north as oriented with the north to south flow of the Connecticut River), Survey Area 9106 (Discharge Canal) is to the east, Survey Unit 9106-0013 is to the south. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0013 Survey Unit 9106-0013 (Discharge Canal) is designated as Final Status Survey (FSS) Class 2 and consists of approximately 9,011 m (2.23 acres) of water covered sediment in an area located approximately 0.80 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. This survey unit comprises the southern portion of the permanent wetland area. The survey unit is bounded as follows: Survey Unit 9106-0012 is to the north (called north as oriented with the north to south flow of the Connecticut River), Survey Area 9106 (Discharge Canal) is to the east, Survey Area 9531 is to the south and west. The survey unit comprises the canal sediments to the depth of three (3)feet from the top of the sediment layer or to the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0014 Survey Unit 9106-0014 (Discharge Canal) is designated as Final Status Survey (FSS) Class I because its characterization data indicated that some samples may exceed the Operational DCGL. It consists of approximately 1,870 m2 (0.46 acres) of water covered sediment in an area located approximately 0.16 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is bounded as follows: Survey Unit 9106-0001 is to the north (called north as oriented with the north to south flow of the Connecticut River), Survey Unit 9522 is to the east, Discharge Canal Survey Unit 9106-0002 is to the south and land surface area 9520 is to the west. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or the original construction depth and it extends up the canal banks to the mean high water level.

Survey Unit 9106-0015 Survey Unit 9106-0015 (Discharge Canal) is designated as Final Status Survey (FSS) Class 1 because an FSS sample from Survey Unit 9106-0007 (9106-0007-017F) was found to exceed the Operational DCGL for the area. It consists of approximately 1,170 m2 (0.29 acres) of water 32

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 covered sediment in an area located approximately 0.81 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Discharge Canal is a man-made mile long waterway that runs parallel to, and ultimately communicates with the Connecticut River. The survey unit is completely surrounded by Discharge Canal Survey Unit 9106-0007. The survey unit comprises the canal sediments to the depth of three (3) feet from the top of the sediment layer or to the original construction depth.

Survey Unit 9508-0000 Survey Unit 9508-0000 (Pond) is designated as Final Status Survey (FSS)

Class 3 and consists of approximately 10,831 m2 (2.67 acres) of water covered sediment in an area located approximately 0.09 miles from the reference coordinate system benchmark used at the Haddam Neck Plant (HNP). The Pond is man-made and served as a fire suppression reservoir.

The pond receives run off from the east mountain side and from a trench that is located east of the Radiological Control Area (RCA) boundary drainage trench, the trench was isolated prior to FSS activities. The Pond ultimately communicates with the Connecticut River. The Pond survey unit is bounded as follows: land survey area 9506-0000 surrounds the entire pond. The following land surfaces areas are in close proximity to the pond: Survey Area 9504-0000 is to the east, Survey Area 9514-0000 is to the south and Survey Area 9512-0000 is to the west.

3.3 Summary of Historical Radiological Data The site historical radiological data for HNP includes the results of the scoping surveys completed in 1998, augmented characterization surveys in 1999, a characterization report in 2000, a historical site assessment supplement in 2001, characterization surveys, and remedial action surveys performed up to the time of FSS.

3.3.1 Scoping Surveys The purpose of the scoping survey was to establish early in the decommissioning process, the necessary areas requiring remediation and to what extent. Details of the scoping surveys are provided in the Reference 7.17. The scoping survey identified 140 events that could have potentially contaminated the facility outside of the Radiological Control Area (RCA). From the 140 identified events, the scoping survey report listed those events most likely to have impacted the HNP site outside the RCA. These events were:

• Leak from the Radioactive Water Storage Tank (RWST) heater valve in November 1973 that contaminated the storm drain system; 33

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006

• Multiple waste gas tank rupture disc actuations in the 70's;

" Various leaks in the steam generator blowdown waste discharge line and the service water effluent line under the Primary Auxiliary Building (PAB) floor in the 1976 to 1980 time period;

• Contamination of the yard area around the Borated Water Storage Tank (BWST) from leaks in the circulating water heater line in 1978;

• Unplanned radioactive release from the degasifier through the plant stack in December 1979;

• Leak from a cracked weld seam in the auxiliary building exhaust duct to the main stack in September 198 1;

• Draining of the Spent Fuel Pool (SFP) heat exchanger to an uncontrolled drain that emptied into the 115 kV switchyard trench in April 1984;

" Resin liner overflows in 1984;

" Sediment dredged out of discharge canal was stored in boneyard burm [sic] area in 1986;

• Drain hose spill of contaminated water to yard area in August 1987;

• Contaminated water from radioactive waste processing dumped into an uncontrolled drain that emptied into the 115 kV switchyard trench in February 1989;

" Spill of component cooling water to the storm drain in March 1990;

• Leak from the refueling water storage tank in September 1990;

• Spill from the reactor coolant system to the pipe trench in August 1991; and,

• Waste material disposed of at on site permitted landfill in south east comer of site starting in 1974.

3.3.2 Characterization Surveys The characterization of radiological and hazardous materials conditions of all areas of the HNP site, an initial task in the plant decommissioning and license termination process, centered around four main objectives:

• Determine the nature and extent of contamination; 34

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006

• Provide the basis for initial classification of areas;

• Provide a basis for remediation planning, including recommendations for additional surveys or samples; and

• Provide input into the Final Status Survey design.

Following plant shutdown at the end of 1996, it was determined that there was a need for additional surveys to better define the scope of radioactivity or "characterization" in several on-site areas.

To fill this gap, surveys were conducted in plant areas along with the sampling and analysis of environmental media that included ground water, paved surfaces outside the RCA and soils suspected of containing radioactive materials. The coalescence of this data, as well as all available site data, occurred during the development of the HSA. The HSA consisted of a review of plant operational records since initial license approval, a review of events that have potential impact on decommissioning activities compiled in accordance with Title IOCFR50.75(g)(1), and interviews with present and former employees regarding events and activities that impact license termination.

The results of the HSA identified radiological conditions or events that impacted the HNP. These events fall into several categories:

" Normal plant operation that affected systems, components and building surfaces that are designed to contain radioactive material. Examples of these are the reactor coolant system, residual heat removal pumps and building areas such as sumps and pipe vaults;

• The discharge and runoff of radiological effluents to the canal;

• Operational events that occurred in which radioactive materials were released from ventilation, and waste processing systems.

Examples are elevated readings on the Primary Auxiliary Building roof and owner controlled hillside locations east of the plant; and,

• Leakage of water containing radioactive material that was documented historically. Incidents of this nature included leaking lines under the PAB drumming room floor, overflowing of a manhole just east of the Service Building and leakage from radioactive liquid storage tanks.

The summary information developed during the HSA process was evaluated concurrently with the information provided in the "NRC Historical Review Team Report - Radiological Control and Area 35

Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey FinalReport - PhaseIV November, 2006 Contamination Issues at Haddam Neck" (Reference 7.38), dated March 26, 1998, to assure completeness of the historical data.

The Characterization Report provided an assessment of the radiological and hazardous material conditions for each of the site buildings and subsections of the site grounds at a specific point in time. A listing of the areas was provided in the table of contents, along with the area identification number(s) and the area's initial classification in accordance with the criteria established in MARSSIM. Site maps were provided to locate the areas and the respective survey area number(s). A report for each area contained a description (boundaries) of the area, known radiological and hazardous material information, impacted systems within an area and recommendations for further samples or surveys. Buildings assumed to remain in support of spent fuel storage activities, were not included (i.e. not considered at that time to be part of the HNP LTP as they would remain under license, to store the spent fuel).

As suggested in the Characterization Report, and discussed in the applicable HNP LTP and Survey Unit Release Records, additional characterization surveys would be needed to aid in the FSS plan design.

3.3.3 Remedial Action Surveys All survey areas submitted in this FSS Final Report were evaluated in accordance with Health Physics Department Technical Support Document (TSD) BCY-HP-0078, "ALARA Evaluation of Soil Remediation in Support of Final Status Survey (Reference 7.39)." This evaluation determined that remediation beyond that required to satisfy the release criteria to be unnecessary, and that the remaining residual radioactivity in soil was ALARA.

During the phase of decommissioning and surveying covered by this FSS Final Report, remedial action and Remedial Action Survey (RAS) were performed on one (1) survey unit (9106-0001) which required remediation. A documented RAS was performed on the remediated dredge spoils media. It was determined that the remediation was completed when dredge materials from the survey unit were below the operational DCGL unitized concentrations.

3.4 Conditions at the Time of Final Status Survey The survey areas discussed in this FSS Final Report are either water covered or permanent wetlands areas. Construction activities were 36

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 complete, and the areas were turned over to the Site Closure Group for the implementation of isolation and controls.

Prior to FSS, areas ready for survey were isolated and controlled under procedure GGGR-R5116-002, "Area Preparation for Final Status Survey Activities RPM 5.1-16." (Reference 7.40) This included posting of the areas as well as notifications to site personnel. Permission to enter and work in these areas had to be obtained from the Site Closure Group.

Obvious postings of the boundaries in the areas controlled public access; however, the impact of public access to the final radiological condition of the areas was considered minimal to nonexistent.

3.5 Identification of Potential Contaminants In general, the identification of potential contaminants was accomplished through the review of plant operating records, radiological surveys and laboratory analysis for ETD gamma emitting radionuclides. During characterization, soil samples collected from areas that would undergo FSS were sent to an off site laboratory for HTD analysis. The HTD analysis usually included chemical separation or other advanced methods of detection not available at HNP.

As shown by the FSS Survey Unit Release Records, the plant-related radionuclides identified most often in the samples were Cs-137 and Co-60.

Other radionuclides, from both the ETD and HTD list provided in Table 2-3, have been identified in survey areas covered under this FSS Final Report. It is very likely that many of these are false positives and were counted as positive detects because the criterion used at HNP is highly conservative. The HNP criterion for accepting as a positive detection was any reported result greater than two standard deviations uncertainty. In almost every case, radionuclides that were considered detected by the HNP criterion, were reported in concentrations that were less than the MDC. In any event, all the radionuclides listed in Table 2-3 were included in the DQO process when designing an FSS plan and during the DQA when reviewing the adequacy of the FSS plan.

3.6 Radiological Release Criteria The radiological release criteria is based on Title 10CFR20, Subpart E, where dose from residual radioactivity that is distinguishable from background radiation results in a Total Effective Dose Equivalent (TEDE) to an average member of a critical group that does not exceed twenty five (25) mrem/yr; and, all residual radioactivity is reduced to levels that are ALARA. The HNP LTP had established DCGLs (e.g., Base Case Soil DCGLs) to demonstrate compliance with the release criterion of less than or equal twenty five (25) mrem/yr.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 A reduction to the Base Case Soil DCGLs had to be performed to ensure compliance with the release criterion of 25 mrem/yr TEDE when all three (3) pathways (soil, existing groundwater and future groundwater) are potentially present. The reduced quantity is the Operational DCGL which was administratively set in accordance with the values listed in Table 2-1.

4.0 FINAL STATUS SURVEY PROTOCOL 4.1 Data Quality Objectives The DQO process as outlined in Section 2.1 of this report was applied for each FSS Plan and contains basic elements common to all FSS plans at HNP. An outline of those elements presented in the HNP Final Status Survey Plans are as follows:

• STATE THE PROBLEM The problem: To demonstrate that the level of residual radioactivity in a survey unit including any areas of elevated activity does not exceed the release criterion.

Stakeholders: The primary stakeholders interested in the answer to this problem are Connecticut Yankee Atomic Power Company, the CT Department of Environmental Protection (CTDEP) and the US Nuclear Regulatory Commission (USNRC).

The Planning Team: The planning team consisted of the Site Closure personnel. The primary decision maker was the assigned FSS Engineer. The FSS Engineer obtained input from CYAPCO Project Support on issues relating to schedule and costs.

Schedule: The approximate time to complete an FSS plan and collect field data. Constraints and other activities that may have limit access to areas or hamper survey and sampling was also addressed.

Resources: The primary resources needed to determine the answer to the problem were ANSI N18.-1971 qualified Health Physics Technicians to perform fieldwork, FSS Engineers to prepare the plan, generate maps, coordinate field activities and evaluate data. An off-site laboratory would be needed to analyze the samples and provide quality radionuclide specific results.

• IDENTIFY THE DECISION PrincipalStudy Question: Does the average concentration of residual radioactivity in the survey unit exceed the release criteria?

Alternate Actions: Alternative actions include failure of the survey unit, remediation, reclassification and no action.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Yankee Atomic Power Company Connecticut Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 The Decision: If the average concentration of residual radioactivity in the survey unit exceeds the release criteria, then the survey unit fails.

• IDENTIFY THE INPUTS TO THE DECISION Information Needed: New measurements of sample media would be needed to determine the concentration and variability of the radionuclides present at the site at the time of final status survey, the extent of any areas of elevated activity, and the results of statistical outliers relative to the rest of the measurements.

Source of the Information: A review of historical information, IOCFR50.75(g)(1) files, and radiological surveys providing an indication of the potential for contamination.

Sampling and Analysis Methods to Meet the Data Requirements:

Sediment core samples were collected down to a depth of three (3) meters, or greater in some cases. Analyses included radionuclide specific measurements to identify and quantify the ETD and HTD radionuclides listed in Table 2-3.

Laboratory analysis results included actual calculated results.

Results reported as <MDC were not accepted for FSS. Results included reporting error, observed MDC and data qualifiers as appropriate.

Determiningthe OperationalDCGL:

Table 2-3 lists twenty (20) radionuclides potentially present at the site.

Derived Concentration Guideline Levels (DCGLs) were calculated for each of the radionuclides listed based on a limit of twenty five (25) mrem/yr NRC dose limit and a CTDEP dose -limit of nineteen (19) mrem/yr. To calculate DCGLs, dose models were developed to relate levels of residual radioactivity to potential dose. The DCGLs presented in Table 2-2 were developed for exposures from three (3) potential media, which is residual radioactivity in soil, existing groundwater contribution, and future groundwater contribution. In the HNP LTP, Equation 5-1 expresses the total dose (Hvotai) from all three (3) media, which is shown below:

HTotaI can be expressedas:

HTotal = Hsoi + HExisfingGW + HFutureGW (HNP LTP Equation 5-1)

The dose contribution from the existing groundwater and future groundwater contamination, the second and third components of HNP LTP Equation 5-1, are addressed on a survey unit basis as shown in Table 1-1.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 Following characterization, the data was evaluated to determine if any of the twenty listed radionuclides would be present in quantities greater than 5% of the applicable individual Operational DCGL or an aggregate concentration exceeding 10%. If multiple radionuclides were assumed present (e.g., Cs-137, Co-60) then the individual Operational DCGLs would be used in conjunction with the unity rule to demonstrate compliance.

As verification, a minimum of 5% of the samples required for compliance were analyzed for all radionuclides listed in Table 2-3.

Any radionuclides listed in Table 2-3 verified present in FSS samples were included in the assessment of data and incorporated into the decision process as necessary.

A decision to use surrogate DCGLs was evaluated based on radionuclide analysis. During Phase III FSS surrogates were not used.

Survey and Analysis Methods to Meet the Data Requirements: The HNP LTP requires that MDCs for fixed measurements (samples are considered fixed measurements) be as far below the DCGL as possible. A value of 10% is the desired level of sensitivity with up to 50% of the DCGL being acceptable. The Minimum Detection Concentrations (MDCs) for soil samples were typically less than 10% of the Operational DCGL.

All activities fall under the FSSQAP. This plan requires, among other things, the use of trained technicians, calibrated instruments and procedures. In addition to these requirements, a minimum of 5%

of the required number of samples were selected for QC evaluation which consisted of field replicate splits.

Based on survey unit class, an elevated measurement comparison test (EMC) was sometimes applicable. The EMC test is applicable and was designed for, in all Class 1 survey units. For each Class 1 survey unit, direct measurements above the operational DCGL were bounded for area extent and evaluated using the EMC test.

The EMC test does not apply for Class 2 or Class 3 units.

Basis for Determining the Action Level: The Action Level provides the criterion used during the decision process for choosing among alternative actions (e.g., whether to take action or not to take action or whether to choose Action I versus Action 2). The Action Levels associated with implementing the HNP LTP are based on regulatory requirements and are linked to the evaluation of FSS data.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 The first step in evaluating FSS data for a given survey unit was to draw simple comparisons between the measurement results and the release criterion, which for FSS, is identified with the Operational DCGL used in conjunction with the unity rule, when applicable. The result of these comparisons would be one (1) of four (4) conclusions shown in Table 4-i.

Table 4-1 Action Levels Evaluation Result Conclusion A plant-related radionuclide other Re-evaluate the Operational than those planned for has been DCGL detected.

All reported concentrations are less The survey unit meets the than the Operational DCGL () release criterion The average concentration is less than the Operational DCGL (1)but an individual sample exceeds Operational Conduct the Sign Test DCGL ()

The average concentration exceeds The survey unit does not meet Operational DCGL (1) the release criterion (1) Used in conjunction with the unity rule, when applicable.

• DEFINE THE BOUNDARIES OF THE SURVEY.

Boundaries of the survey: The actual physical boundaries as stated for each survey unit.

Temporal boundaries: Estimated times and dates for the survey.

Sampling in a survey unit was normally performed only during daylight and dry weather.

Constraints: The most common constraints were the weather, water level and overgrowth that limited navigation.

• DEVELOP A DECISION RULE The following decision rule was developed to define a logical process for choosing among alternative actions for the principal study questions associated with each survey unit. The decision rule is based on the Action Levels listed in Table 4-1.

The Decision: If the mean concentration of residual radioactivity in the survey unit exceeds the Operational DCGL in conjunction with unity rule, when applicable, then the survey unit fails to meet the release criteria.

• SPECIFY TOLERABLE LIMITS ON DECISION ERRORS The Null Hypothesis: Residual radioactivity in the survey unit exceeds the release criteria.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 Type I Error: This is the x error. This is the error associated with incorrectly concluding that the null hypothesis was rejected. The HNP LTP has set the x error at 0.05 (5%) unless prior approval is granted from the USNRC to use a less restrictive value. Therefore, a value of 0.05 (5%) was used for survey planning and data assessment for FSS.

Type 11 Error: This is the P error. This is the error associated with incorrectly concluding that the null hypothesis was accepted. A value of 0.05 (5%) was used for survey planning and data assessment for these survey units.

The Lower Bound of the Gray Region (LBGR): The LBGR is set or adjusted during the optimization phase of the DQO process.

Relative Shift (A/u): The relative shift will be maintained within the range of 1.0 and 3.0 by adjusting the LBGR in accordance with Reference 7.14.

• OPTIMIZE DESIGN Type of statistical test: The Sign Test was selected as the statistical test for FSS.

The Sign Test is conservative as it increases the probability of incorrectly accepting the null hypothesis (i.e., the conclusion would have been the survey unit does not meet the release criteria) and would not require the selection or use of a background reference area.

Number of samples for non-parametric statistical sampling: The number of samples for non-parametric statistical sampling was determined using Reference 7.23. The LBGR was set to obtain a relative shift in the range of 1 and 3. The locations of the samples were determined using Visual Sample Plan (VSP) software in accordance with procedure RPM 5.1-14, "Identifying and Marking Locations for Final Status Survey" (Reference 7.42) and the appropriate grid spacing for the assigned class (i.e. random or systematic). VSP was created by Pacific Northwest National Laboratory (PNNL) for the United States Department of Energy.

Number of judgmental samples and locations: The selection of judgmental or biased samples was at the discretion of the FSS Engineer. Locations chosen for sampling were usually areas of interest (obvious disturbance of soil, collection points from run-off and erosion, small piles, trenches, etc).

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey FinalReport - PhaseIV November, 2006 Number of scan areas and location: The LTP exempts the water and wetland areas surveyed in the Phase IV report from scan survey requirements.

Number of samples for Quality Control: The number of quality control samples usually exceeded 10% percent of the sample set.

The locations for split samples was selected randomly using the Microsoft Excel RAND function.

Investigation Levels: Investigation levels are established in the HNP LTP for the various classifications. Investigation levels may prompt additional survey and analysis to identify areas of elevated activity.

The investigation level for a soil sample measurement includes individual radionuclide results greater than the Operational DCGL used in conjunction with the unity rule.

Power Curve: A Prospective Power Curve was generated using COMPASS, a software package developed under the sponsorship of the United States Nuclear Regulatory Commission (USNRC) for implementation of the MARSSIM in support of the decommissioning license termination rule (10 CFR 20, Subpart E). The result of the COMPASS computer run showed adequate power for the survey designs.

4.2 Survey Unit Designation and Classification Procedure RPM 5.1-10, "Survey Unit Classification," (Reference 7.43) defines the decision process for classifying an area in accordance with the HNP LTP and MARSSIM. During the FSS of areas submitted for Phase IV FSS Final Report two (2) areas were subdivided or reclassified.

4.3 Background Determination As previously stated, "background" for soil samples was not calculated nor included in the DCGL comparisons to sample data. However, Reference 7.41 and Reference 7.44 provided justification and support in determining the origins of non-HNP derived Cs-137 and Sr-90 encountered during the sampling campaign. None of the radionuclide concentrations believed to be non-HNP derived were subtracted from the DCGL comparisons.

4.4 Final Status Survey Plans The level of effort associated with planning a survey is based on the complexity of the survey and nature of the hazards. To assist the Site Closure FSS Engineers when preparing survey plans to support Final Status Surveys, guidance is provided in Reference 7.14.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Yankee Atomic Power Company Connecticut Haddam Neck Plant Final Status Survey FinalReport - Phase IV November, 2006 4.5 Survey Design 4.5.1 Determination of Number of Data Points The number of samples was determined in accordance with Reference 7.23. A summary of survey design data points is provided in Table 4-2.

Table 4 Number of Surfce Samples for FSS Survey Unit Survey Design Biased Investigation Samples Samples 1 Samples 9106-0001 30(2) 8 9106-0002 15 - -

9106-0003 16 1 -

9106-0004 15 1 8 9106-0005 15 1 4 9106-0006 15 2 4 9106-0007 15 - -

9106-0008 14 9106-0009 15 -

9106-0010 15 1 9106-0011 15 -

9106-0012 15 -

9106-0013 15 - -

9106-0014 42(2) - 8 9106-0015 28 - 4 9508-0000 15 2 -

(1) The number of biased samples was determined during the DQO process and augmented as necessary by addendums to the FSS plan (2) The sample population calculated for the Sign Test was doubled in these survey units in accordance with an agreement made with the State of Connecticut, Department of Environmental Protection.

4.5.2 Sample Locations Locations of the samples were determined using software Visual Sample Plan (VSP) in accordance with Reference 7.42. Pacific Northwest National Laboratory (PNNL) created VSP for the United States Department of Energy. This software was verified and validated by Health Physics Technical Support Document (TSD) BCY-HP-0079, "Use and Verification of Visual Sample Plan" (Reference 7.45). The TSD contains documentation including a user's manual for VSP Version 2.0 and verification documentation.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 VSP software imports a topographical map of the selected survey area and, once provided with the number of required samples, type of grid pattern (triangular or square), and the starting point for the grid pattern (random starting point), then develops the survey design and designates the sample location coordinates based on the Connecticut State Plane System. The coordinates are then imported into the GPS for use in finding the sample location in the field.

For those locations where access was impractical on dry land or unsafe, the location was either moved within a three (3) meter radius of the original point or an alternate random sample location was generated. In either case, the decision to relocate a sample location is documented in the Daily Survey Journal.

4.6 Instrumentation The DQO process evaluates the ability of the instrument to measure radioactivity at levels below the applicable DCGL. Since the LTP exempts all Phase IV survey areas, which are water covered or wetlands, from scanning, These DQOs are not relevant.

4.7 Survey Methodology 4.7.1 Scan Surveys The HNP LTP specifies that scan surveys are not required for the discharge canal or pond areas.

4.7.2 Soil Sampling Measurement locations were identified in North American Datum (NAD) 1927 coordinates that were supplied to the sampling vendor, Ocean Surveys, Inc. (OSI) of Old Saybrook, Connecticut.

Discharge Canal sampling was accomplished using direct push technology to collect composite samples of bottom and mean high water mark sediments. Sediment cores from the Discharge Canal were obtained by OSI using a vibrating corer that is platform mounted on a sampling vessel. The core barrel was a three (3) inch diameter thin-walled aluminum tube which also served as a core liner (ten (10) feet or less). A core catcher was available to prevent the sample from sliding out of the bottom of the tube. Vessel positioning and the determination of sample locations were accomplished using a GPS interfaced with a navigation and data logging system.

45

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 4.7.3 Total Surface Contamination Measurements "Total Surface Contamination Measurements" refers to the FSS of structural surfaces such as walls, floors and ceilings. During this phase of FSS and submittal, no areas containing structures subject to FSS were surveyed.

4.8 Quality Control Surveys Reference 7.24 establishes a method for evaluating QC split samples collected in support of FSS. QC split sample data was assessed on criteria taken from the USNRC Inspection Manual, Inspection Procedure 84750, "Radioactive Waste Treatment and Effluent and Environmental Monitoring," March 1994 (Reference 7.46).

A minimum of five percent (5%) of the sample locations used in the FSS design were selected randomly using the Microsoft Excel "RAND" function and submitted as "splits." All splits taken during FSS were field replicates, that is, samples obtained from one location, homogenized, divided into separate containers and treated as separate samples. These samples were used to assess errors associated with sample heterogeneity, sample methodology and analytical procedures. It was desirable that when analyzed, there would be agreement between the splits resulting in data acceptance. When there is not agreement between the samples, the FSS Engineer evaluated the magnitude and impact on FSS plan design, and the need to perform confirmatory sampling. When the FSS Engineer has determined that the discrepancy affects quality or is detrimental to the FSS program then the discrepancy warranted the issuance of a Condition Report (Reference 7.24).

To maintain the quality of the FSS, isolation and control measures are implemented until there is no risk of recontamination from decommissioning or the survey area has been released from the license.

Following FSS, until the area is released, a semi-annual surveillance has been performed on the survey units covered by this FSS Final Report. The surveillance included an inspection of area postings, inspection of the area for signs of dumping or disturbance and some sampling from selected locations, when warranted. In the event that isolation and control measures are compromised, a follow-up survey may be performed after evaluation.

5.0 SURVEY FINDINGS Reference 7.26 provides guidance to Site Closure personnel to interpret survey results using the DQA process during the assessment phase of FSS. Although 46

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 intended for FSS activities, the DQA process could be used for other radiological data collection activities (e.g., characterization and remedial action surveys). The extent to which of the DQA process applies for these surveys would be commensurate with the objectives of the particular survey.

The DQA process is the primary evaluation tool to determine that data are of the right type, quality and quantity to support the objectives of the sample plan (e.g.,

FSS Plan and the requirements of the HNP LTP). The five steps of the DQAs process are:

• Review the sample plan Data Quality Objectives (DQOs) and the survey design;

• Conduct a preliminary data review;

• Select the statistical test;

• Verify the assumptions of the statistical test, and,

• Draw conclusions from the data.

Data validation descriptors described in MARSSIM Table 9.3 was used during the DQA process to verify and validate collected data as required by the FSSQAP.

5.1 Survey Data Conversion During the data conversion, the FSS Engineer will evaluate raw data for problems or anomalies encountered during the Final Status Survey Plan (FSSP) activities (sample collection and analysis, handling and control, etc.) including the following:

• Recorded data;

• Missing values;

• Deviation from established procedure; and,

• Analysis flags.

Once resolved, initial data conversion, which is part of preliminary data review was performed and consists of converting the data into units relative to the release criteria (i.e., pCi/g), and calculating basic statistical quantities (e.g., mean, median, standard deviation). Table 5-1 provides a summary of the data analysis for each survey unit of Phase IV. The individual FSS Release Records covered by this FSS Final Report provide additional detail.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant Yankee Atomic Power Company Connecticut iladdam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Table 5 Summary of Statistical Analysis for Sediment Samples Standard Maximum Mean D iation Operational Survey Class DCGL f-DCGL(') f-DCGL(') Deviation (mrem/yr) 9106-0001 1 17 1.458 0.241 0.300 9106-0002 2 17 0.382 0.113 0.100 9106-0003 2 17 0.611 0.185 0.201 9106-0004 2 17 0.873 0.300 0.272 9106-0005 2 17 0.531 0.116 0.164 9106-0006 2 19 0.843 0.165 0.226 9106-0007 2 19 0.502 0.131 0.140 9106-0008 2 19 0.439 0.113 0.143 9106-0009 2 19 0.438 0.160 0.111 9106-0010 2 19 0.240 0.059 0.072 9106-0011 2 19 0.322 0.103 0.087 9106-0012 2 19 0.023 0.007 0.007 9106-0013 2 19 0.026 0.006 0.008 9106-0014 1 17 1.052 0.209 0.255 9106-0015 1 19 1.180 0.164 0.142 9508-0000 3 19 0.162 0.021 0.041 (1) f-DCGL is used to denote the fraction of the Operational DCGL here 5.2 Survey Data Verification and Validation Items supporting DQO sample design and data were reviewed for completeness and consistency. This includes:

• Classification history and related documents;

• Site description;

• Survey design and measurement locations;

• Analytic method, detection limit and that the required analytical method(s) were adequate for the radionuclides of concern;

• Sampling variability has been provided for the radionuclides of interest;

• QC measurements have been specified;

• Survey and sampling result accuracy has been specified;

• MDC or MDA limits have been provided;

• Field conditions for media and environment are assessed.

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Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - Phase IV November, 2006 Documentation, as listed, was reviewed to verify completeness and that it is legible:

• Field and analytical results;

• Chain-of-custodies;

• Daily Survey Journals;

• Instrument downloads; and,

• Measurement results relative to measurement location.

After completion of these previously mentioned tasks, a Preliminary Data Review record was initiated. This record serves to verify that all data are in standard units in relation to the DCGLs and requires the calculation of the statistical parameters needed to complete data evaluation. Included at a minimum are the following parameters:

• The number of samples or measurements;

• The range of observations (i.e., minimum and maximum values);

• Mean;

• Median; and,

• Standard deviation.

Considerations as an optional aid to evaluate the data set are the coefficient of variation, measurements of relative standing, such as percentile and other statistical applications as necessary (frequency distribution, skew etc.). Finalization of the data review consists of graphically displaying the data in distributions and percentiles plots.

5.3 Evaluation of Number of Sample and Measurement Locations in Survey Units An effective tool utilized to evaluate the number of samples collected in the sampling scheme is the Retrospective Power Curve generated by COMPASS. The Retrospective Power Curve shows how well the survey design achieved the DQOs. For reporting purposes, all Survey Unit Release Records included a Retrospective Power Curve analysis indicating that the sampling design had adequate power to pass FSS release criteria (i.e. adequate number of samples was collected).

The Sign Test was the selected statistical test for all Survey Unit Release Records covered under this FSS Final Report. This test was performed in accordance with procedure RPM 5.1-21, "Applying the Sign Test,"

(Reference 7.47). All the data for the survey units covered under this FSS 49

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 Final Report passed the Sign Test and the null hypothesis was rejected.

The FSS design has been satisfied.

During this FSS, the need to apply the Elevated Measurement Comparison (EMC) Test was required to evaluate areas exceeding the DCGL in three (3) Class 1 survey units covered in this report. These are Survey Units 9106-0001, 9106-00014 and 9106-0015.

5.4 Comparison of Findings with Derived Concentration Guideline Levels In conjunction with performing the Sign Test, and the generating of a Retrospective Power Curve, the data were compared to the Table 4-1 criteria and the decision rule provided in the FSSP. Based on the comparison, and non-parametric statistical sampling (i.e., the Sign Text),

the survey unit may either fail or pass.

Investigations are accomplished through the issue of an addendum to the FSS plan. When the investigational criteria are exceeded, additional evaluation is done to understand the extent and mechanism for the apparent elevated response. Several actions may occur which include bounding the elevated area with multiple samples. Information collected from this type of plan provides additional information for statistical analysis and may stimulate further considerations to reclassify, remediate and resurvey. It should be noted that one (1) or more samples exceeding the Operational DCGL may not constitute failure of the survey unit and a viable option is to do nothing more in this area.

5.5 USNRC/Independent Verification Team Findings The USNRC/ORISE has not performed independent verification work in the Phase IV survey areas as of the submittal date of this document.

6.0

SUMMARY

The sixteen (16) survey units covered under this FSS Final Report have met the criteria of the applicable FSS plans. However, the FSS results provided herein only address the dose component from soil as provided in the HNP LTP Equation 5-1. The second component of HNP LTP Equation 5-1, dose contribution due to existing groundwater, is bounded by either 2 mrem/yr or zero (0). The dose contribution from the third component of HNP LTP Equation 5-1, future groundwater, is zero (0) since there are no underground structures, systems or components containing residual radioactive material within the groundwater saturated zone in the survey areas.

7.0 REFERENCES

7.1 Haddam Neck Plant License Termination Plan 50

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey Final Report - PhaseIV November, 2006 7.2 ISC 06-024, "Initial Target Operational DCGLs/Dose Targets for CY",

August 2, 2006.

7.3 NUREG-1575, Multi-Agency Radiation Survey and Site Investigation Manual MARSSIM) 7.4 ISC-GQP-00001 -003, "Final Status Survey Quality Assurance Plan" (FSSQAP) 7.5 GPP-GGGR-R5120-002, "Final Status Survey Program (RPM 5.1-00)"

7.6 NUREG-1757, Volume 2, Consolidated NMSS Decommissioning Guidance-Characterization, Survey, and Determination of Radiological Criteria 7.7 GPP-GGGR-R5122-001, "Preparation of Final Status Survey Reports (RPM 5.1-22)"

7.8 W. Norton (CYAPCO) to USNRC, "Letter of Intent Concerning the Release of the East Site Grounds from the Part 50 License", dated April 29, 2004 (CY-04-069 / Docket No. 50-213) 7.9 J. D. Donahue (USNRC) to K. Heider (CYAPCO), "Haddam Neck Plant -

Issuance of Amendment RE: Approval of License Termination Plan",

dated November 25, 2002 7.10 T. Smith (USNRC) to W. Norton (CYAPCO), "Haddam Neck Plant -

Release of East Site Grounds from Part 50 License", dated September 01, 2004 7.11 J. Bourassa (CYAPCO) to USNRC, "Final Status Survey (FSS) Final Report Phase II", March 8, 2005 (CY-05-040/ Docket No. 50-213 7.12 W. Norton (CYAPCO) to USNRC, "Letter of Intent Concerning the Phased Release (Phase II Release Area) from the Part 50 License", dated October 5, 2005 (CY-05-194 / Docket No. 50-213) 7.13 T. Smith (USNRC) to W. Norton (CYAPCO), "Haddam Neck Plant -

Release of Phase II from Part 50 License", dated February 28, 2006 7.14 "Final Status Survey Report - Phase III", May 04, 2006 7.15 "Final Status Survey Report - Phase III", Revision 1 September 9, 2006 7.16 GGGR-R5111-002, "Preparation of Final Status Survey Plans" (RPM 5.1-11)"

7.17 "Results of Scoping Surveys", September 1998 7.18 "Augmented Characterization Survey Report", January 1999 7.19 "Characterization Report", January 2000 7.20 "Historical Site Assessment Supplement" August 2001 51

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 7.21 GPP-GGGR-R5400-000, "Site Closure Training Program (RPM 5.4-00)"

7.22 GGGC-00001-004, "Work Plan and Inspection Record" 7.23 GGGR-R5112-001, "Determination of the Number of Surface and Subsurface Samples for FSS of Open Land Areas (RPM 5.1-12)"

7.24 GPP-GGGR-R5124-000, "Split Sample Assessment for Final Status Survey (RPM 5.1-24)"

7.25 GPP-GGGR-R51004-003, "Chain of Custody for Final Status Survey Samples (RPM 5.1-5)"

7.26 GGGR-R5123-000, "Data Quality Assessment (DQA), (RPM 5.1-23)"

7.27 "Quality Assurance Program for Haddam Nuclear Plant," (CYQAP) 7.28 CY Quality Surveillance Report QSR 06-001-CY 7.29 CY Quality Assurance Audit CY-06-A06-01 7.30 Self Assessment 06-01 "Final Status Survey Field Activities" 7.31 CY Condition Report (CR)05-781 7.32 Self Assessment 06-02 "Final Status Survey Field Activities" 7.33 Self Assessment 06-03 "Final Status Survey Field Activities" 7.34 Condition Report (CR)06-223 7.35 Post Shutdown Decommissioning Activities Report (PSDAR) 7.36 Updated Final Safety Analysis Report (UFSAR) 7.37 US NRC NUREG CR-5849 "Manual for Conducting Radiological Surveys in Support of License Termination" 7.38 "NRC Historical Review Team Report - Radiological Control and Area Contamination Issues at Haddam Neck" USNRC, dated March 26, 1998 7.39 CYAPCO Health Physics Department Technical Support Document BCY-HP-0078, "ALARA Evaluation of Soil Remediation in Support of Final Status Survey 7.40 24265-000-GPP-GGGR-R5116-002, "Area Preparation for Final Status Survey Activities (RPM 5.1-16)"

7.41 Health Physics Technical Support Document (TSD) BCY-HP-0063, "Background Cs-137 Concentration in Soil."

7.42 GGGR-R5114-001, "Identifying and Marking Locations for Final Status Survey (RPM 5.1-14)".

7.43 GPP-GGGR-R51 10-001, "Survey Unit Classification (RPM 5.1-10) 52

Connecticut Yankee Atomic Power Company Haddam Neck Plant FinalStatus Survey FinalReport - PhaseIV November, 2006 7.44 EPRI Technical Report 1003030, "Determining Background Radiation Levels in Support of Decommissioning Nuclear Power Plants."

7.45 Health Physics Technical Support Document (TSD) BCY-HP-0079, "Use and Verification of Visual Sample Plan" 7.46 USNRC Inspection Manual, Inspection Procedure 84750, "Radioactive Waste Treatment and Effluent and Environmental Monitoring," March 1994.

7.47 GPP-GGGR-R5121-00l, "Applying the Sign Test (RPM 5.1-21)"

8.0 Appendices Al Survey Unit Release Record 9106-0001, Discharge Canal A2 Survey Unit Release Record 9106-0002, Discharge Canal A3 Survey Unit Release Record 9106-0003, Discharge Canal A4 Survey Unit Release Record 9106-0004, Discharge Canal A5 Survey Unit Release Record 9106-0005, Discharge Canal A6 Survey Unit Release Record 9106-0006, Discharge Canal A7 Survey Unit Release Record 9106-0007, Discharge Canal A8 Survey Unit Release Record 9106-0008, Discharge Canal A9 Survey Unit Release Record 9106-0009, Discharge Canal A1O Survey Unit Release Record 9106-0010, Discharge Canal All Survey Unit Release Record 9106-0011, Discharge Canal A12 Survey Unit Release Record 9106-0012, Discharge Canal A13 Survey Unit Release Record 9106-0013, Discharge Canal A14 Survey Unit Release Record 9106-0014, Discharge Canal A15 Survey Unit Release Record 9106-0015, Discharge Canal A16 Survey Unit Release Record 9805-0000, Pond 53