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Final Status Survey Final Report Phase VI - Book 1 of 18
	ML070740543
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	02/12/2007
From:	Randall D; Connecticut Yankee Atomic Power Co
To:	; Office of Nuclear Material Safety and Safeguards
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4;j 1 i EookS lf 1 I 41 I:.L Final Status Survey Final Report Phase VI Connecticut Yankee Atomic Power Company Haddam Neck Plant .VOsToR Haddam, Connecticut February 2007 0 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February 2007 Prepared By: Reviewed By: Approved By: Dale Randall- FSS Engineer~~ McC hy -FSS Engineer Clyde Newson -Technical Support Manager Date: ?- /2-07 Date: 2 Date: 2-ti i7 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 TABLE OF CONTENTS 1.0 Introduction

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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

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21 2.4 Survey Data Assessment

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22 2.5 Quality Assurance and Quality Control M easures ........................................

23 3.0 Site Information

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26 3.1 Site Description

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26 3.2 Survey Area/Unit Description

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27 3.3 Summary of Historical Radiological Data ....................................................

32 3.4 Conditions at the Time of Final Status Survey .............................................

36 3.5 Identification of Potential Contaminants

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36 3.6 Radiological Release Criteria ......................................................................

37 4.0 Final Status Survey Protocol .............................................................................

37 4.1 Data Quality Objectives

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37 4.2 Survey Unit Designation and Classification

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43 4.3 Background Determination

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43 4.4 Final Status Survey Plans .............................................................................

43 4.5 Survey Design ...............................................................................................

44 4.6 Instrumentation

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45 4.7 Survey M ethodology

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50 4.8 Quality Control Surveys ...............................................................................

52 5.0 Survey Findings ...............................................................................................

53 5.1 Survey Data Conversion

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53 5.2 Survey Data Verification and Validation

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54 5.3 Evaluation of No. of Sample and Measurement Locations in SUs ...............

55 5.4 Comparison of Findings with Derived Concentration Guideline Levels ..........

56 5.5 USNRC/Independent Verification Team Findings ......................................

56 6.0 Summary ...............................................................................................................

56 7.0 References

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57 8.0 Appendices

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60 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 LIST OF TABLES 1-1 Phase VI Survey Unit Classification and Description List ..........................

5 2-1 Derived Concentration Guideline Levels for Soil .......................................

15 2-2 HNP LTP Compliance Equation 5-1 Values and Actual Soil Dose ....................

16 2-3 FSS A rea C lassifications

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18 2-4 Easy-to-Detect (ETD) and Hard-to-Detect (HTD) Radionuclides

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20 4-1 A ction L evels .................................................................................

4 1 4-2 Number of Samples for FSS ...............................................................

44 4-3 SPA-3 Technical Details and Specifications

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46 4-4 Ambient Background Count Rates, Associated MDCR's and Investigation Levels 47 4-5 Scan C overage .................................................................................

50 4-6 Summary of Total Area Scanned .........................................................

51 5-1 Summary of Statistical Analysis for Soil Samples ......................................

54 LIST OF FIGURES 1-1 Phase V I Subm ittal ......................................................................

6 1-2 FSS Final Report Phased Submittal Areas ..............................................

10 2-1 FSS O rganizational Chart ..................................................................

12 2 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007

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 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 section 2-1 of this report and Integrated Site Closure (ISC) memo 06-024, "Initial Target Operational DCGLs / Dose Targets 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); HNP program document ISC-GQP-00001-003, "Final Status Survey Quality Assurance Plan" (Reference 7.4); HNP 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.3 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 This report contains a compilation of seventeen (17) Survey Unit Release Records that are within the Phase VI scope. The Phase VI FSS Final Report specifically addresses sixteen (16) surface soil areas of the HNP site that total approximately twenty three and one half (23.5) surface acres in size (95,000 mi 2). In addition Phase VI encompasses one (1) sub surface soil survey unit, with an area of approximately (2.86) acres (11,568 mi 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 HNP site, as well as, survey unit boundaries.

All FSS 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 VI survey units.The survey data for all Phase VI 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 2-2). The additional requirement of 1OCFR20.1402 that all residual radioactivity be reduced to levels that are As Low As Reasonably Achievable (ALARA)has also been satisfied.

4 Connecticut Yankee Atomic Power Company Final Status Survey Final Report -Phase VI Haddam Neck Plant February, 2007 Table 1-1 Phase VI Surve Unit Classification and Description List Survey Survey Class General Description of the Survey Unit (Area Unit 9304 0001 2 Southwest Protected Area Grounds (4,800 mn 2)9304 0002 1 Southwest Protected Area Grounds (1,268m 2)9504 0000 3 Bypass Road and Secondary Parking Lot (5,645m 2)9506 0000 3 North Site Grounds (Non-Protected Area)(11,244 m 2)9512 0000 3 Northwest Site Grounds (Non-Protected Area)(30,701 n 2)9522 0001 2 Southeast Site Grounds (Non-Protected Area)(6,972 M 2)9522 0002 1 Southeast Site Grounds (Non-Protected Area)(1,913 m 2)9522 0003 1 Southeast Site Grounds (Non-Protected Area)(1,997 M 2)9522 0004 1 Southeast Site Grounds (Non-Protected Area)(1,386 M 2)9522 0005 1 Southeast Site Grounds (Non-Protected Area)(1,947 in 2)9522 0006 1 Southeast Site Grounds (Non-Protected Area)(1,987 m 2)9522 0007 1 Southeast Site Grounds (Non-Protected Area)(1,952 m 2)9527 0005 2 East Mountain Side (5,777 M 2)9527 0006 1 East Mountain Side (790 m 2)9539 0001 3 ISFSI Haul Road (Northern section) (9,332, m 2)9539 0002 3 ISFSI Haul Road (Southern Section) (7,293, n 2)9804 0000 C Subsurface area associated with Southeast Grounds (11,568 M 2)(1) Refer to Section 3.2 for a more detailed description.

5 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report- Phase VI February, 2007 6 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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.

HNP 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, HNP submitted a request to release a portion of the HNP site (Reference 7.8) from the 1OCFR50 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), HNP determined the proposed action would have no adverse impact on the ability of the site in aggregate to meet 1OCFR20, 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 I1 FSS Final Report On March 8, 2005, HNP submitted a request to release a portion of the HNP site (Reference 7.11) from the 1OCFR50 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), HNP determined the proposed action would have no adverse impact on the ability of the site in aggregate to meet 1OCFR20, 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 USNRC on February 28, 2006 (Reference 7.13).Phase III FSS Final Report On May 4, 2006, HNP 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 USNRC 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 Final Status Survey Final Report -Phase VI February, 2007 1 of the Phase III report and the associated revised release records were submitted to the USNRC on September 9, 2006 (Reference 7.15).Phase IV FSS Final Report On November 29, 2006, HNP submitted the Phase IV FSS Report (Reference 7.16). This submittal comprised the FSS release records for a total of sixteen (16) surface survey units, and included the pond and discharge canal survey areas. Two (2) of the sixteen (16) survey units were permanent wetland areas, the balance were water covered locations.

Sediments were sampled in these areas by performing direct push sample coring to the appropriate depths to meet the dose model.Phase V FSS Final Report On December 7, 2006, 1HNP submitted the Phase V FSS Report (Reference 7.17). This submittal comprised the FSS release records for a total of nine (9) surface survey units, and two (2) subsurface survey units, which collectively made up the area defined as Phase V. This area covered the northern portion of the peninsula, as indicated in Figure 1-2.Phase VI FSS Final Report The subject of this report.Phase VII FSS Final Report As discussed above, HNP anticipates at least one (1) additional FSS Final Report submittal.

Below is a list of the remaining survey areas 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 the remaining submittal 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 HNP's intent to maintain the basic submittal milestone schedule provided below. However, because of potential changes in the decommissioning schedule, it is possible that an additional, interim submittal may be filed with the USNRC with the goal of providing Survey Unit Release Records as soon as possible to support the agency's review, as well as HNP's goals regarding the release of site lands from the license.8 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 Phase VII FSS Final Report Submittal scheduled for May 2007 (17 Release Records)9302-0000 9306-0000 9312-0001 9312-0002 9312-0003 9312-0004 9312-0005 9312-0006 9312-0007 9312-0008 9312-0009 9312-0010 9313-0000 9514-0000 9801-0000 9802-0000 9803-0000 Northwest Protected Area Grounds South Central Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Northeast Protected Area Grounds Central site Grounds Primary Parking Lot Subsurface Soils in Radiologically Controlled Area Subsurface Soils Associated with 9308 Subsurface Soils Located North of Industrial Area 9 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 Figure 1-2, FSS Final Report Phased Submittal Areas CONNECTICUT YANKEE ATOMIC POWER COMPANY GENERAL ARRANGEMENT DRAWING Final Status Survey Final Report Phased Submittals 10 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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 HNP site to demonstrate that the premises are suitable for release in accordance with the criteria for decommissioning in Title lOCFR20, 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 1OCFR20.1402.

To implement the FSS Program as provided in Reference 7.5, and MARSSIM, HNP established an organization within the Integrated 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 Site Closure Directorate.

11 Connecticut Yankee Atomic Power Company Final Status Survey Final Report -Phase VI Figure 2-1 FSS Organizational Chart Haddam Neck Plant February, 2007 r ---------------------------------------------------

Technical Support Group Manager Integrated Site Closure Group 12 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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 HNP 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 7.18), is a series of graded, planning steps found to be effective in establishing criteria for data quality and developing survey plans.13 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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 Levels (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 5-3 of the HNP LTP. Table 2-1 provides a listing of the Base Case and required MDC values.14 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 Table 2-1 Derived Concentration Guideline Levels for Soil Base Case Soil Radionuclide DCGL (pCi/g) Required MDC (pCi/g)(25 mrem/yr) (1.0 mrem/yr)H-3 4.12E+02 1.65E+01 C-14 5.66E+00 2.26E-01 Mn-54 1.74E+O1 6.96E-01 Fe-55 2.74E+04 1.1OE+03 Co-60 3.81E+00 1.52E-01 Ni-63 7.23E+02 2.89E+01 Sr-90 1.55E+00 6.20E-02 Nb-94 7.12E+00 2.85E-01 Tc-99 1.26E+01 5.04E-01 Ag-108m 7.14E+00 2.86E-01 Cs- 134 4.67E+00 1.87E-01 Cs-137 7.91E+00 3.16E-01 Eu-152 1.01E+01 4.04E-01 Eu-154 9.29E+00 3.72E-01 Eu-155 3.92E+02 1.57E+O1 Pu-238 2.96E+01 1.18E+00 Pu-239/240 2.67E+01 1.07E+00 Pu-241 8.70E+02 3.48E+O1 Am-241 2.58E+01 1.03E+00 Cm-243/244 2.90E+O1 1.16E+00 (1) Bold indicates those radionuclides considered to be Hard-to-Detect (HTD).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 (HTotal) from all three (3) media, which is shown below: Hrotal can be expressed as: HToal = Hsoi + H Existing GW + HFutureGW (HNP LTP Equation 5-1)15 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 The total dose, HT 0-rl, 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 the HNP is nineteen (19) mrem/yr TEDE. Therefore, the value for HvotaI is effectively nineteen (19)mrem/yr for all survey units. To determine the Hsoij (the dose equivalent for the Operational DCGLs) one must subtract the existing and future groundwater dose values as shown below.H soil =Hrotal -HExistingGW

-HFuIureGW (Operational DCGL dose equivalent)

The present and future groundwater terms were bounded on an individual survey unit basis as discussed in Integrated Site Closure (ISC)memo 06-024, "Revised Target Operational DCGLs/Dose Targets for CY" (Reference 7.2). Table 2-2 summarizes the HNP Equation 5-1 values for each of the survey units discussed in this report. Table 2-2 also shows the actual soil dose equivalent based on the survey unit data analyses.Table 2-2 HNP LTP Compliance Equation 5-1 Values and Actual Soil Dose Existing Ground Future Ground Allowable Actual Survey Water Dose Water Dose Soil Dose Soil Dose Unit (mrem/yr)

(1) (mrem/yr)

(2) (mrem/yr)

(3)9304-0001 2 2 15 0.06 9304-0002 2 2 15 0.08 9504-0000 2 0(4) 17 0.37 9506-0000 0 0(4) 19 0.25 9512-0000 2 0(4) 17 0.63 9522-0001 2 0 17 3.13 9522-0002 2 0 17 2.94 9522-0003 2 0 17 1.18 9522-0004 2 0 17 0.73 9522-0005 2 2 15 0.18 9522-0006 2 2 15 0.80 9522-0007 2 2 15 0.79 9527-0005 2 0 17 3.16 9527-0006 2 0 17 6.91 9539-0001 2 0 17 0.28 9539-0002 2 0 17 0.16 9804-0000 2 2 15 0.10 (1) These bounding values were taken from ISC memo 06-024, "Initial Target Operational DCGLs/Dose Targets for CY" (Reference 7.2); the maximum allowable groundwater dose is 8 mrem/yr to meet the HNP LTP release criteria for unrestricted use.(2) The Operational DCGL dose equivalent meets the release criteria for unrestricted use, as agreed to with the CTDEP, of 19 mrem/yr plus ALARA.16 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 (3) The average dose based on the average residual radioactivity in soil following FSS. This value doesn't incorporate additional dose for any elevated areas in Class I areas.(4) The Emergency Operations Facility (EOF) Building is located within the survey unit.Several storage sea lands are located in the northern portion of the survey unit. These sea lands are used for storage and prep of FSS samples and miscellaneous materials.

The EOF structure will remain on site and several underground structures will be abandoned in place (i.e. a septic system; two (2) electric/telephone duct banks; a well water storage tank; and several storm water culverts associated with the bypass road.) Radiological surveys will be performed to confirm that the components or structures will meet all applicable unrestricted release criteria.(CY memo CY-06-093-Reference 7.19).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 consolidated in the "Results of Scoping Surveys" (Reference 7.20);"Augmented Characterization Survey Report" (Reference 7.21);"Characterization Report" (Reference 7.22); "Historical Site Assessment Supplement (HSA)" (Reference 7.23); and, in files containing copies of records maintained pursuant to Title 1OCFR50.75(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 the 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 17 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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 FSS. Survey units were limited in size based on classification, exposure pathway modeling assumptions, and site-specific conditions.

Particular attention was given to survey unit boundaries and surface areas to ensure building foundation footprint coverage.

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.Table 2-3 FSS Area Classifications Survey Unit Surface Area Limit Contamination Classification Potential Structures:

Class 1 (floor area) Upth10t Land Area: Up to 2,000 m 2 Highest Class A Subsurface:

No limit Structures:

100 m 2 to 1,000 m 2 Class 2 (floor area) Moderate Land Area: 2,000 m 2 to 10,000 m 2 Class B Subsurface:

No limit Structures:

Class 3 (floor area) No limit Lowest Land Area: Class C Subsurface 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 18 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 guidance using an integrated approach and combinations of fixed measurements, traditional scanning surveys, and other advanced survey methods, as appropriate, to evaluate survey units relative to their applicable release criteria.Another important facet of the DQO process is to identify the radionuclides of concern and determine the concentration variability.

During characterization and in preparation for FSS, the HNP Radiochemistry Lab, using gamma spectroscopy, analyzed soil samples collected from random and biased locations in the survey units for Easy-to-Detect (ETD) radionuclides (Table 2-4). The on-site results were augmented, in most cases, by analyses performed by an off-site laboratory for both ETD radionuclides and Hard-to-Detect (HTD) radionuclides (Table 2-4). Characterization 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.Although the HNP LTP only required a minimum of 5% (for subsurface soil samples), typically 10% of all the soil samples, and in some cases a higher percentage, were analyzed for HTD by the off-site laboratory.

Sr-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.

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 1OCFR20 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 assessments.

19 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 Table 2-4 Easy-to-Detect (ETD) and Hard-to-Detect (HTD) Radionuclides Radionuclide (1) 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 Gamma Spectroscopy Am-241 (2) ETD ALWAYS Alpha Spectroscopy Cm-243/244 HTD AS NEEDED Alpha Spectroscopy (1) Bold indicates those radionuclides considered to be Hard-to-Detect (HTD).(2) Americium-241 can be analyzed by gamma and alpha spectroscopy and is considered to be Easy to Detect (ETD); the preferred result is the alpha spectroscopy's when both analyses are performed.

Soil sample locations were determined randomly for Class 3 survey units, or by a triangular systematic grid with a random starting point for Class 1 and 2 survey units using commercially available software.

Similarly, for sub-surface units, locations were determined randomly for Class C survey units, or by a triangular systematic grid with a random starting point for Class A and B survey units.Soil sample locations were identified in North American Datum (NAD)1927 coordinates and were loaded into the GPS software.

Each FSS plan provided a map and GPS positions to FSS field supervision for reference.

In each survey unit, a minimum of five (5) percent of the samples were 20 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 collected for quality control analysis such as "splits" or duplicates.

All survey units passed the quality control acceptance criteria.Off-site 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 method, radioisotope, result and uncertainty of two (2) standard deviations, laboratory data qualifiers, units and required MDC.A consideration of survey design was the need to use "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 used for some of the survey units 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 Starting 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 7.24);" Implementation of a work control process including applicable health and safety procedures under GGGC-00001-004, "Work Plan and Inspection Record" (Reference 7.25);21 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007* 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 7.26);" 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 measurement and sample locations, and investigation levels and corrective actions under procedure GGGR-R5111-002, "Preparation of Final Status Survey Plans" (RPM 5.1-11) (Reference 7.18);* 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 7.27) 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 7.28); 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 (DQA) (RPM 5.1-23)" (Reference 7.29).The FSS implementation an d completion process resulted in the generation of field logs, and radionuclide specific analysis.

Data were stored electronically on the HNP 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.22 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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 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; 23 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007* 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.

The off-site laboratories used for analysis of the samples collected during FSS maintain Quality Assurance Plans designed for their facility.

HNP reviews these plans, as required by the "Quality Assurance Program for the Haddam Neck Plant (CYQAP)," (Reference 7.30) 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 Integrated 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 ANSI N 18.1-1971 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.Quality Surveillance activities are ongoing in 2007, documentation of these will be provided with the Phase VII FSS Report.During 2006, three (3) Quality Surveillance Reports (QSR) were 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.

24 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 QSR-06-01-CY (Reference 7.31) 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.

QSR-06-007 (Reference 7.32) performed during November of 2006, concluded that a sampling of the Survey Unit Release Records to be submitted in Phase IV were consistent with the HNP LTP and FSS programmatic requirements.

QSR-06-008 (Reference 7.33) performed from November of 2006, to December of 2006, concluded that a sampling of the Survey Unit Release Records to be submitted in Phase V was consistent with 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 requirements of the License Termination Plan and associated regulatory requirements.

AUDIT CY-06-A06-01 (Reference 7.34) 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.

The Integrated Site Closure Group 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 7.35), performed in April 2006, was performed as a follow-up to Condition Report (CR)05-781 (Reference 7.36). The issues identified involved soil sample collection, particularly samples used for quality control. The Self Assessment provided recommendations for improvement.

SCA-06-02 (Reference 7.37) 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 7.38) performed in November, 2006, was performed as an investigation of the cause of Condition Report (CR) 06-25 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 0223 (Reference 7.39). The CR identified an issue with split sample agreement.

The Self Assessment observed that media homogenization for samples from the pond and discharge canal were 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 have been corrected and systematic controls implemented.

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 on-site 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 was responsible for site development, design of buildings and secondary systems, and all plant construction.

Each of these contractors were responsible to HNP 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 HNP.On December 4, 1996, HNP permanently shut down after approximately 28 years of operation.

On December 5, 1996, HNP notified the USNRC 26 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 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, HNP began the decommissioning of the site. The Post Shutdown Decommissioning Activities Report (PSDAR) (Reference 7.40) was submitted, in accordance with Title 10CFR50.82 (a)(4), on August 22, 1997, and was accepted by the USNRC. On January 26, 1998, HNP transmitted an Updated Final Safety Analysis Report (UFSAR)(Reference 7.41) to reflect the plant's permanent shutdown status, and on June 30, 1998, the USNRC amended the HNP Facility Operating License to reflect the plant condition.

On October 19, 1999, the 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).After extensive analyses and comparison of fuel pool and dry cask storage, CY chose the dry cask option for storing its 1019 spent fuel assemblies.

The location for the new Independent Spent Fuel Storage Installation (ISFSI), which is on CY's 500-plus acres about three-quarters of a mile from the reactor site, was selected from eight carefully researched areas.In 1997, in accordance with NUREG/CR-5849 (Reference 7.42) 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 August 2006 through January 2007 (additional detail is provided in the Survey Unit Release Records).

During this period, the approximately twenty-three and one half (23.5) acres of open land areas of the HNP site received a FSS.The HNP site maintains a reference coordinate system based on GPS coordinates consistent with the Connecticut State Plane System. A benchmark was established as an origin for documenting survey efforts and results. The benchmark, 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 survey unit Release Records to this FSS Final Report.27 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report 7 Phase VI February, 2007 Each of the attached survey unit Release Records references the distance from a survey unit's nearest point to a North American Datum 1927 (NAD 1927) location.

To support decommissioning activities, this datum location has been relocated to a permanent fixed location at coordinates Northing 237370.20, Easting 667394.57.

The distances shown in the descriptions reflect the distance of the nearest portion of a survey unit to this datum location.Survey Unit 9304-0001 Survey Unit 9304-0001 (Southwest Protected Area Grounds) is designated as Final Status Survey (FSS) Class 2 and consists of 4,800 m 2 (1.186 acres) of uninhabited open land located approximately 1,410 feet from the reference coordinate system benchmark used at Haddam Neck Plant (HNP). The survey unit is comprised of predominantly flat disturbed open land that gently slopes from east to west toward the Connecticut River. At the far western end of the survey unit, the topography changes from flat to steep hillside that falls off to the Connecticut River. The hillside is covered, at the northern end, with large stones and with trees and brush at the southern end.Survey Unit 9304-0002 Survey Unit 9304-0002 (Southwest Protected Area Grounds) is designated as Final Status Survey (FSS) Class 1 and consists of 1,268 m 2 (0.313 acres) of uninhabited open land located approximately 1,483 feet from the reference coordinate system benchmark used at Haddam Neck Plant (HNP). The survey unit is comprised of predominantly flat disturbed open land that gently slopes from east to west toward the Connecticut River.Survey Unit 9504-0000 Survey Unit 9504-0000 (North Parking Lot and Bypass Road) is designated as Final Status Survey (FSS) Class 2 and consists of approximately five thousand six hundred forty five square meters (5,645 mi 2) open land surface soil in an area located approximately 171 feet from the reference coordinate system benchmark used at the HNP. The survey unit is comprised of predominantly flat disturbed open land that gently slopes from east to west toward the Connecticut River.Survey Unit 9506-0000 Survey Unit 9506-0000, North Site Grounds (Non-Protected Area)/EOF, is designated as Final Status Survey (FSS) Class 3 and consists of approximately 11,244 m 2 (2.77 acres) of open land area located at the reference coordinate system benchmark used at HNP. The Storm Water Retention Pond, Survey Unit 9508-0000, is located in the interior of the survey area. The survey unit is comprised of predominately flat open land area. The survey unit slopes from north to south, in the direction of the 28 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase VI February, 2007 pond. The area around the pond is densely populated with trees and small brush.Survey Unit 9512-0000 Survey Unit 9512-0000, Northwest Site Grounds, is designated as Final Status Survey (FSS) Class 3 and consists of approximately 30,701 m 2 (7.58 acres) of open land area located at the reference coordinate system benchmark used at the HNP. The survey unit is comprised of predominately flat open land that slopes, slightly, from east to west toward the Connecticut River. At the far northeastern end of the survey unit, the topography changes from flat to steep hillside.

The hillside is covered with large trees and thick brush. At the southern most section of the survey unit, the area is a steep hillside that falls off to the Connecticut River.Survey Unit 9522-0001 Survey Unit 9522-0001 (Southeast Site Grounds (non-protected area) is designated as Final Status Survey (FSS) Class 2 and consists of approximately six thousand nine hundred and seventy two square meters (6,972 M 2) of uninhabited, undeveloped land and is located approximately 2,055 ft from the reference coordinate system benchmark used at HNP.The survey unit is located along the southern boundary of Survey Area 9522, from the northern transmission tower south to the owner-controlled area fence. It is comprised mostly of rock outcroppings, rock ledge, underbrush and trees. The eastern portion of the survey unit has a moderate slope running east to west. The Independent Spent Fuel Storage Installation (ISFSI) Haul Road runs north to south along the western portion of the survey unit.Survey Unit 9522-0002 Survey Unit 9522-0002 (Southeast Site Grounds (non-protected area) is designated as Final Status Survey (FSS) Class I and consists of approximately one thousand nine hundred thirteen square meters (1,913 mi 2) of uninhabited land and is located 1,888 ft from the reference coordinate system benchmark used at HNP. It is comprised mostly of rock outcroppings, rock ledge, underbrush and trees. The survey unit has a moderate slope running southeast to northwest.

Survey Unit 9522-0003 Survey Unit 9522-0003 (Southeast Site Grounds (non-protected area) is designated as Final Status Survey (FSS) Class 1 and consists of approximately one thousand nine hundred ninety-seven square meters (1,997 M 2) of uninhabited land and is located 1,986 ft from the reference coordinate system benchmark used at HNP. The majority of the survey unit is flat and de-vegetated.