ML070120538
| ML070120538 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 09/21/2006 |
| From: | Gerard van Noordennen Yankee Atomic Electric Co |
| To: | Document Control Desk, NRC/FSME |
| References | |
| CY-06-128 | |
| Download: ML070120538 (68) | |
Text
CONNECTICUT YANKEE ATOMIC POWER COMPANY HADDAM NECK PLANT 362 INJUN HOLLOW ROAD
- EAST HAMPTON, CT 06424-3099 SEP 2 1 2006 Docket No. 50-213 CY-06-128 Re: 10 CFR 50.82(a)(11)
U. S. Nuclear Regulatory Commission Attention:
Document Control Desk Washington, D. C. 20555-0001 Haddam Neck Plant Final Status Survey (FSS) Final Report -Phase III Revised Release Records for Survey Units 9527-0001 throuqh 9527-0004 In a letter dated May 4, 20061, Connecticut Yankee Atomic Power Company (CYAPCO) submitted the FSS Final Report- Phase Ill. The Phase Ill FSS Final Report addresses seven (7) land areas including the seven (7) Survey Unit Release Records that are within the Phase Ill scope. Table 1 provides a listing of all Survey Units addressed in this report including the classification and general description for each unit.On June 29, 2006 a conference call was held between the NRC Staff and CYAPCO personnel to discuss Staff questions related to the release records for Survey Units 9527-0001 through 9527-0004.
Based on the discussion with the NRC Staff, CYAPCO determined that the release records for Survey Units 9527-0001 through 9527-004 required clarification and revision to some sections of the release records. The main NRC question was the high background noted during the survey. The high background was due to radwaste stored in shipping containers near Survey Area 9527. After the radwaste was moved, the area was resurveyed by CYAPCO and ORISE and found to have lower background levels consistent with expectations.
The purpose of this submittal is to transmit the revised release records for Survey Units 9527-0001 through 9527-0004 and Final Status Survey Report-Phase Ill, Revision 1 (Attachment 1). The attached records document the results and conclusions of the survey units and were prepared in accordance with guidance and requirements contained in the following:
1 G. P. van Noordennen (CYAPCO) letter to U. S. Nuclear Regulatory Commission, "Haddam Neck Plant, Final Status Survey (FSS) Final Report-Phase I1l", dated May 4, 2006.rj ssoD Document Control Desk CY-06-128/Page.2
- Haddam Neck Plant License Termination Plan,* NUREG-1 575, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), Section 8.6 and* NUREG-1757, Volume 2, Consolidated NMSS Decommissioning Guidance -Characterization, Survey, and Determination of Radiological Criteria, Section 4.5.Another NRC question dealt with the allocations of dose when developing DCGLs for Survey Areas. In the Haddam Neck Plant License Termination Plan (HNP LTP)Section 5.4.7.1, Equation 5-1 expresses the total dose contribution from three components; soil contribution, existing ground water contribution and future ground water contribution.
The survey data results for all Phase III Survey Units address the dose component due to soil as provided in the HNP LTP compliance Equation 5-1.The second component of Equation 5-1, existing groundwater contribution was determined to be less than 2 mrem/yr per ISC-06-024 (Attachment 2). The dose contribution from the third component of Equation 5-1, future groundwater, is zero because there are no underground structures, systems or components containing residual radioactivity as noted in these release records. The discussion on the allocation of total dose contribution was revised in the Phase III Final Report consistent with the guidance contained in Attachment 2.CYAPCO hereby requests the NRC review these release records along with the other Survey Unit release records provided previously for acceptance of this portion of the HNP site final radiological survey by October 31, 2006.The previous submittal is updated to Revision 1 by replacing the FSS Final Report and each of the 9527 Release Records (Appendices A2-A5 of the Final Report) with Revision 1 updates.There areno regulatory commitments contained in this submittal.
If you should have any questions regarding this submittal, please contact me at (860) 267-3938.Sincerely, G. P. van Noordennen Date Director of Nuclear Safety and Regulatory Affairs Attachment 1: Revised Release Records for Survey Units 9527-0001 through 9527-0004 Attachment 2: ISC 06-024, "Revised Target Operational DCGLs/Dose Targets for CY"
Enclosures:
Appendices A2-A5 cc: S. J. Collins, NRC Region 1 Administrator T. B. Smith, NRC Project Manager, Haddam Neck Plant M. T. Miller, Chief, Decommissioning Branch, NRC Region 1 E. L. Wilds, Jr., Director, CT DEP Radiation Division TABLE 1 Phase III Survey Unit Classification and Description List Survey Survey Class General Description of the Survey Unit Revision Area Unit 9521 0000 3 Southwest pond (25,456 M 2) 0 9527 0001 2 East Mountain Side (8,600 M 2) 1 9527 0002 2 East Mountain side (9,740m 2) 1 9527 0003 2 East Mountain Side (8,200 M 2) 1 9527 0004 2 East Mountain Side (3,500 M 2) 1 9528 0002 2 Southwest Mountain Side (9,752 M 2) 0 9531 0000 3 South End of Peninsula (108,222 M 2) 0 Docket No. 50-213 CY-06-128 Attachment 1 Haddam Neck Plant Final Status Survey Report -Phase III, Revision 1 September 2006 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Report -Phase III, Revision 1 September 2006 Prepared By: Reviewed By: Approved By: Dale Randall -FSS Engin~er Jack carthy -FSS Engineer Clyde Newson -Technical Support Manager Date: -2 Date: 7/21,/Date: 9/24/, 6 I Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 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 ...............................................................................................
17 2.3 Survey Implementation
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20 2.4 Survey Data Assessment
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21 2.5 Quality Assurance and Quality Control M easures ........................................
22 3.0 Site Information
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25 3.1 Site Description
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25 3.2 Survey Area/Unit Description
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27 3.3 Summary of Historical Radiological Data ....................................................
29 3.4 Conditions at the Time of Final Status Survey .............................................
32 3.5 Identification of Potential Contaminants
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33 3.6 Radiological Release Criteria .....................................................................
34 4.0 Final Status Survey Protocol .............................................................................
35 4.1 Data Quality Objectives
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35 4.2 Survey Unit Designation and Classification
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41 4.3 Background Determination
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41 4.4 Final Status Survey Plans .............................................................................
42 4.5 Survey Design ...............................................................................................
42 4.6 Instrumentation
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43 4.7 Survey M ethodology
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47 4.8 Quality Control Surveys ..............................................................................
49 5.0 Survey Findings .................................................................................................
50 5.1 Survey Data Conversion
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50 5.2 Survey Data Verification and Validation
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51 5.3 Evaluation of Number of Sample and Measurement Locations in Survey Units 52 5.4 Comparison of Findings with Derived Concentration Guideline Levels ..........
53 5.5 USNRC/Independent Verification Team Findings ......................................
53 6.0 Summary ...............................................................................................................
54 7.0 References
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54 8.0 Appendices
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57 I Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 LIST OF TABLES 1-1 Phase III Survey Unit Classification and Description List 4 2-1 Derived Concentration Guideline Levels for Land Area FSS 14 2-2 FSS Area Classifications 16 2-3 Easy-to-Detect (ETD) and Hard-to-Detect (HTD) Radionuclides 17 4-1 Action Levels 37 4-2 Number of Surface Samples for FSS 40 4-3 SPA-3 Technical Detail and Specifications 41 4-4 Ambient Backgound Count Rates, Associated MDCRs, and Investigation Levels 42 4-5 Scan Coverage 45 4-6 Summary of Total Area Scanned 46 5-1 Summary of Statistical Analysis for Cs-137 49 LIST OF FIGURES 1-1 Phase III Submittal 5 1-2 FSS Final Report Phased Submittal Areas 9 2-1 FSS Organizational Chart 11 2 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006
1.0 INTRODUCTION
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 address the dose component due to soil as provided in the HNP License Termination Plan (LTP) compliance Equation 5-1. The second component of HNP LTP Equation 5-1, the dose contribution due to present groundwater has been determined to not exceed 2 mrem/yr in the Survey Units included in this submittal (Reference 7.1). All Phase III survey areas were not considered impacted by future groundwater radioactive contamination, as there are no foundations or footings containing residual radioactive material within the groundwater saturated zone in the area. The dose contribution from future groundwater, the third component of HNP LTP Equation 5-1, is therefore, zero.(HNP LTP Equation 5-1) HTotai --HsIol + H ExisingGW
+HFFutureGW Table 1-1 specifies each of the possible dose values to be applied in each term of HNP LTP compliance Equation 5-1. Since the State of Connecticut, Department of Environmental Protection (CTDEP) dose limit for total dose is more restrictive than the Federal requirement; the lower value (19 mrem/yr) is used to demonstrate compliance with the federal limits. Until recently, the groundwater dose could not be bounded with enough precision to specify soil dose limits with great confidence.
Consequently, each of the FSS plans for Survey Units in this report was designed to a lower soil dose limit (i.e. they were designed to either 8 or 10 mrem/yr).Table 1-1 Index of Compliance Eauation Terms Equation 5-1 term Dose Reference (mrem/yr)HTotal (NRC) 25(1) CY LTP HTotal (State) 19 CY commitment to the (CTDEP)H(Existing GW) 0 or 2 Site Closure memo ISC 06-024 H(Future GW) 0 or 2 Site Closure memo ISC 06-024 Hsoil 15, 17 or 19 Site Closure memo ISC 06-024 (1) This must be reduced to 19 to demonstrate compliance with the CT state criteria.3 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1.1 Executive Summary This report is a summary of Phase III Final Status Survey (FSS) activities.
All FSS activities were performed consistent with the guidance provided in the HNP LTP (Reference 7.2); 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)" (FSSQAPP), (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.This Phase III FSS Final Report specifically addresses seven (7) land area survey units within the east mountainous and lowland survey areas of the HNP site that total approximately forty three (43) surface acres in size.This report contains a compilation of seven (7) Survey Unit Release Records that are within the Phase III scope. 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 designed and implemented under approved procedures.
Trained and qualified individuals, using properly calibrated instruments and laboratory equipment that are sensitive to the suspected contaminants, performed the FSS of the Phase III survey units. The survey data for all Phase III survey units demonstrate that the dose from residual radioactivity in soil is less than the maximum annual dose criterion for license termination for unrestricted use specified in 10CFR20.1402.
The additional requirement 4
Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 of 1OCFR20.1402 that all residual radioactivity be reduced to levels that are As Low As Reasonably Achievable (ALARA) has also been satisfied.
Table 1-1 Phase Ill Survey Unit Classification and Description List Survey Survey Area Unit Class General Description of the Survey Unit ()9521 0000 3 Southeast Pond, land area (25,456 in 2)9527 0001 2 East Mountain Side; land area (8,600 mi 2)9527 0002 2 East Mountain Side; land area (9,740 M 2)9527 0003 2 East Mountain Side; land area (8,200 mi 2)9527 0004 2 East Mountain Side; land area (3,500 M 2)9528 0002 2 Southeast Mountain Side; land area (9,752 M 2)9531 0000 3 South End of Peninsula; land area (108,222 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 III, Revision 1 September, 2006 Figure 1-1, Phase II Submittal 6 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 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 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 United States Nuclear Regulatory Commission (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 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 November 25, 2002 (Reference 7.12), CYAPCO 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 survey areas from the site was approved by the NRC on February 28, 2006 (Reference 7.13).Phase III FSS Final Report The subject of this report.7 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 Phases IV. V. VI and VII Final Reports As discussed above, CYAPCO anticipates at least four (4) 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, duration, 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 USNRC 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.Phase IV FSS Final Report Submittal scheduled for October 2006* 9106 Discharge Canal* 9508 Pond Phase V FSS Final Report Submittal scheduled for November 2006* 9520 Southwest Site Storage Area* 9530 Central Peninsula Area* 9805 Subsurface Soils associated with the Peninsula* 9807 Subsurface Soils associated with 9520-0004 Phase VI FSS Final Report Submittal scheduled for December 2006* 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 Phase VII FSS Final Report Submittal scheduled for February 2007* 9302 Northwest Protected Area Grounds* 9306 South Central Protected Area Grounds* 9312 Northeast Protected Area Grounds* 9313 Central Site Grounds 8.
Connecticut Yankee Atomic Power Company Connctiut Ynke Atoic owerComanyHaddam Neck Plant Final Status Survey Final Report -Phase 111, Revision 1 September, 2006* 9514 Primary Parking Lot* 9527 East Mountain Side* 9801 Subsurface Soils in Radiologically Controlled Area* 9802 Subsurface Soils Associated with 9304, 9306 and portions of 9522 9803 Subsurface Soils Located North of Industrial Area 9 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase HII, Revision 1 September, 2006 Figure 1-2, FSS Final Report Phased Submittal Areas CONNECTICUTYANKEE ATOMIC POWER COMPANY GENERAL ARRANGEMENT DRAWING Final Status Survey Final Report Phased Submittals INITIAL CREATION DATE: 11/15/04 1 LEGEND: I I CREATED BY:. e Chaderoy SrTE PROPERTY UNE SITE 8OUNDARY REVISION DATE: N/A SURVEY AREA BOUNDARY REVISION #: 0 MAP #: 1-2 10 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 Septemeber, 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 HNP 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
-which states that, 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 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.
This report contains only the results of the FSS that addresses the dose due to soil in HNP LTP Equation 5-1. The second component of HNP LTP Equation 5-1, dose contribution due to present groundwater has been determined to not exceed 2 mrem/yr in those survey units included in this submittal (Reference 7.1). All survey areas covered under this FSS Final Report were not considered impacted by future groundwater radioactive contamination, as there are no underground foundations or footings containing residual radioactive material within the groundwater saturated zone in any of the areas. The dose contribution from future groundwater, the third component of the HNP LTP Equation 5-1, is therefore zero.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 1-NP 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.
11 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 Figure 2-1 FSS Organizational Chart Director of Project Support I Radiation Protection Manager TechniclSupport Fss Project Lead RCRA H ealth Group Manager Physics FSS Engineers FSS Supervisors Ground Water ]FSS Technicians Integrated Site Closure Group 12 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 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.Developed and implemented during the initial phase of planning, DQOs 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 7.14), 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 III, Revision 1 September, 2006 Used extensively during FSS, the DQO approach consists of the following seven steps:* State the Problem- provides a clear description of the problem, identification of planning team members (especially the decision-makers), a conceptual model of the hazard to be investigated and the estimated resources;" Identify the Decision-consists of developing a decision statement based on a principal study question, which is typically "Does residual radioactive contamination present in the survey unit exceed the release criteria?" The alternative actions may include no action, investigation, resurvey, remediation and reclassification;" Identify the Inputs to the Decision-depends on the type of media under consideration (e.g., soil, water, concrete) and whether existing data are sufficient or new data are needed to make the decision;" Define the Boundaries of the Decision-spatial boundaries include the entire area of interest including soil depth, area dimensions, contained water bodies and natural boundaries, as needed; temporal boundaries include those activities impacted by time-related events including weather conditions, seasons, operation of equipment under different environmental conditions, resource loading and work schedule;" Develop a Decision Rule- the statement that defines a logical process for choosing among alternative actions;* Specify Tolerable Limits on Decision Errors- incorporates hypothesis testing and probabilistic sampling distributions to control decision errors during data analysis; and," Optimize the Design for Obtaining Data- leads to the development of an adequate survey design.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 additional future groundwater radioactivity from underground foundations or footings.14 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 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 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.The Base Case Soil DCGL for Cs-137, and the DCGLs for all the other radionuclides potentially present in soil, were administratively reduced to 17 mrem/yr to ensure compliance with the dose criteria.
Refer to section 3.6 of this report for more information on release criteria.
These Operational DCGLs, used in conjunction with the unity rule when multiple radionuclides were present, set the minimum sensitivities required for the available survey instruments Minimum Detectable Concentration (MDC) and techniques, and in some cases, the spacing of fixed measurements or samples within a survey unit. Table 2-1 provides a listing of the DCGLs used for the Phase III FSS Final Report.Table 2-1 Derived Concentration Guideline Levels for Land Area FSS Base Case Soil Operational DCGL Required Radionuclide DCGL (pCi/g) (pCi/g) MDC (pCi/g)(25 mrem/yr) (17 mrem/yr) (1.0 mrem/yr)H-3 412.00 280.00 16.50 C-14 5.66 3.85 0.23 Mn-54 17.40 11.80 0.70 Fe-55 27400.00 18600.00 1100.00 Co-60 3.81 2.59 0.15 Ag-108m 7.14 4.86 0.29 Ni-63 723.00 492.00 28.90 Sr-90 1.55 1.05 0.06 Nb-94 7.12 4.84 0.29 Tc-99 12.60 8.57 0.50 Cs-134 4.67 3.18 0.19 Cs-137 7T91 5.38 0.32 Eu-152 10.10 6.87 0.40 Eu-154 9.29 6.32 0.37 Eu-155 392.00 267 15.70 Pu-238 29.60 20.1 1.18 Pu-239/240 26.70 18.20 1.07 Pu-241 870.00 592.00 34.80 Am-241 25.80 17.5 1.03 Cm-243/244 29.00 19.7 1.16 15 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 7.15);"Augmented Characterization Survey Report" (Reference 7.16);"Characterization Report" (Reference 7.17); "Historical Site Assessment Supplement (HSA)" (Reference 7.18); and, in files containing copies of records maintained pursuant to Title 1OCFR 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, 1927 (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 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 16 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 identification, survey units were assigned the area four-digit code and a sub-code to designate the Survey Unit within the survey area (e.g. Survey Unit 9528-0002).
Table 2-2 provides an outline for classification and area limits.Table 2-2 FSS Area Classifications Survey Unit Surface Area Limit Contamination Classification Potential Class 1 Land Area: Up to 2,000 m 2 Highest Class A Subsurface:
No limit Class 2 Land Area: 2,000 m 2 to 10,000 m 2 Moderate Class B Subsurface:
No limit Class 3 Land Area: No limit Lowest Class C Subsurface Several survey units have undergone reclassification prior to FSS. Survey area classification 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.
The final classification was reviewed in conjunction with the preparation of the FSS plan, thus helping ensure that all issues pertaining to classification were 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 by employing 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 2-3). 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. These data were used to determine the number of samples required to achieve adequate sample design.17 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 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. "Gross Activity DCGLs" 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 2-3 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 ETD Gamma Spectroscopy HTD Alpha Spectroscopy Cm-243/244 HTD AS NEEDED Alpha Spectroscopy 18 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 Survey design objectives included a verification of the survey instrument's ability to detect the radiation(s) of interest relative to the Operational DCGL. As standard practice to ensure that this objective was consistently met, radiation detection instruments used for FSS were calibrated every six months with a National Institute of Standards and Technology (NIST)traceable source in accordance with HNP procedures.
Instruments were response checked before and after the instrument was used. Minimum Detectable Count Rates (MDCR) were determined in the field prior to survey, and were used to determine levels for investigation.
Control and accountability of survey instruments were maintained and documented to assure the quality and prevent the loss of data.Based upon classification, areas were selected and scanned with gamma radiation detection instruments.
Information obtained during the survey was electronically logged by the instrument for review and analysis.Samples were usually collected at areas exhibiting elevated scan readings unless otherwise denoted and explained in the FSS Release Record. Each sample point was also scanned and the information logged.Soil sample locations were determined randomly for Class 3 survey units, or by a triangular systematic grid with a random start point for Class 2 survey units using commercially available software.
Sample location coordinates were programmed into the GPS, then physically located and marked.Samples were collected horizontally to a depth of 15 cm (6") below the top soil surface. Leaves, rocks and roots were excluded as much as possible from the sample prior to bagging and closure. Routinely, approximately ten percent of the samples collected were designated for quality control analysis such as "splits" or duplicates.
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 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. 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.19 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase 111, Revision 1 September, 2006 Some portion of the Cs-137 and Sr-90 found in the soil samples is certainly attributable to "background" or fallout from atmospheric weapons tests; 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 necessary during the survey of the land areas included in this submittal.
2.3 Survey Implementation Beginning 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 7.19);* Monitoring instrument calibration as detailed in procedure GGGR-R5103-003 "Control and Accountability of Portable Survey Instruments for Final Status Surveys (RPM 5.1-4)" (Reference 7.20);* Implementation of a work control process including applicable health and safety procedures under GGGC-00001-004, "Work Plan and Inspection Record" (Reference 7.21);" 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 7.22);" Determination of the overall survey design and objectives including where measurements or samples were 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 RPM 5.1-11;* 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 7.23) and the FSSQAP;20 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report- Phase III, Revision 1 September, 2006 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 7.24); 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 7.25).The FSS implementation and completion process resulted in the generation of raw data consisting of measurements taken with handheld radiation detection equipment, field logs, and radionuclide specific analysis.
Data were stored electronically on the CYAPCO network server.2.4 Survey Data Assessment 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.
Posting plots, graphical analyses of survey data that depicts the spatial correlation of the measurements are also used to present the data.Prior to proceeding with data evaluation and assessment, the assigned FSS Engineer resolves and documents discrepancies developed through the DQA process.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-21 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 issuance 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 instruments were properly calibrated;
- 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 that who analyzed 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 7.26) and the 22 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 FSSQAP, prior to selection of a laboratory for FSS sample analysis to ensure standards are acceptable.
The on-site laboratory was not employed to analyze FSS samples used for non-parametric statistical sampling.As discussed in Section 2.2, radiation detection instruments used during FSS were calibrated every six months and were response checked before and after the instrument was used. When the instrument was used more than once a day, then an additional response check was performed during a break in the field work (e.g., lunch). The purpose of the additional check was to ensure that the instrument would be satisfactory for use upon return to the field (otherwise it would be taken out of service), and that the previous survey data collected was valid. Control and accountability of survey instruments was maintained and documented in accordance with HNP procedures.
The Site Closure 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 18.1, "Selection and Training of Nuclear Plant Personnel." 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.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 2004, three (3) Quality Surveillance Reports (QSRs) were issued on activities related to FSS. In general, these surveillances were performed to evaluate the adequacy of the implementation of regulatory, HNP LTP and FSS requirements.
QSR-04-072-CY (Reference 7.27) performed during March 29 to April 8, 2004, was an independent review of the FSS program. The HNP LTP, FSS Plans and procedures, inspection of FSS equipment, and FSS data and documentation were evaluated for compliance and adequacy.
The 23 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 assessment considered procedures, organization and performance in evaluating the HNP LTP implementation.
Experience and lessons learned from other FSS programs were considered by the surveillance team. The use of the assessment to evaluate the program was considered a very positive initiative and useful tool for improving performance in the Site Closure group. The surveillance verified that the controls instituted to plan, design, conduct, and evaluate FSS activities at HNP demonstrate compliance with United States Nuclear Regulatory Commission (USNRC)radiological criteria for unrestricted use, the LTP and FSS requirements.
QSR-04-073-CY (Reference 7.28) performed during June 7 to June 16, 2004, evaluated the guidance for preparing, performing, documenting, and approving the FSS Plan for Survey Unit 9537-0000, Permitted Landfill.The surveillance verified that the controls instituted to plan, design, conduct, and evaluate final status surveys at HNP and demonstrate compliance with USNRC radiological criteria for unrestricted use. The FSS Plan was consistent with MARSSIM guidelines.
QSR-04-078-CY (Reference 7.29) performed during April and June of 2004, evaluated the guidance for performing field activities during the FSS for Survey Units 9535-0001, 9535-0002 and 9806-0000.
The surveillance verified that the controls instituted to plan, design, and conduct the FSS at HNP site demonstrate compliance with the USNRC radiological criteria for unrestricted use. The general and specific FSS Plan was consistent with MARSSIM guidelines.
In June of 2004, the "Final Status Survey Program Assessment Report" (Reference 7.30) was issued. The objective of this comprehensive, independent assessment was to evaluate the effectiveness of the FSS program in implementing HNP LTP requirements including a "limited" review of the HNP LTP. Training, instrumentation, documentation, and data management were also assessed during this time. The report concluded that the FSS program contained the necessary elements to meet the HNP LTP requirements to perform FSS of land areas. However, there were three (3) findings in the areas of document and software controls, and training.
Condition Report (CR) 04-0810 (Reference 7.31) and CR 04-0811 (Reference 7.32) was issued to document and implement corrective actions. The training program was revised and controlling procedures issued.An internal audit was performed in November 2004 by CYAPCO. The objective of the CY Nuclear Safety Audit Report, CY-04-A09-01, "Final Status Survey (FSS)/License Termination Plan (LTP)," (Reference 7.33)was to assess compliance with commitments and regulatory requirements and to verify that FSS and HNP LTP implementation was maintained consistent with associated requirements and that implementation was meeting expectations.
Only one (1) deficiency was identified during the 24 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 audit and CR 04-1298, "Failure to process timely License Basis Document Change Request (LBDCR) for the License Termination Plan (LTP)changes," (Reference 7.34) was issued to document and implement corrective actions based on the audit finding.For the period covering calendar year 2005 to date in 2006, three (3) QSRs were issued on activities related to FSS.QSR-05-009-CY (Reference 7.35) performed during January of 2005, evaluated draft Phase II Survey Unit Release Records, and noted a number of issues which were resolved prior to the Phase II submittal.
QSR-05-021-CY (Reference 7.36) performed during January and February of 2005, reviewed selected Survey Unit Release Records of the Phase II submittal, and identified an issue regarding the accounting for groundwater dose contribution which was corrected prior to submittal of the Phase II reports.QSR-06-01-CY (Reference 7.37) 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.
A self assessment was also performed in March 2005 by the Site Closure Group. The objective of Self Assessment 05-01, "Final Status Survey Instrumentation", (Reference 7.38), was to assess the adequacy and effectiveness of the portable survey instrumentation used in the FSS program. Strengths and opportunities for improvement were identified.
No Condition Reports were generated as a result of the self assessment.
In June 2006, the CY quality assurance department performed audit CY-06-A05-01 (Reference 7.39), covering the FSS and LTP. No findings or deficiencies were identified.
All findings from the QSRs, audits and assessments were corrected and systematic controls were implemented as of the publication date of this report.3.0 SITE INFORMATION 3.1 Site Description Haddam Neck Plant, owned by CYAPCO, 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 site benchmark to the site 25 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 boundary of one thousand five hundred and eighty five feet (1,585 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 was 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 7.40) was submitted, in accordance with Title l0CFR50.82 (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 7.41) 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 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 7.42) 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 26 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 I 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 2002 until March 2006 (additional detail is provided in the Survey Unit Release Records).
During this period, on the outlying lands surrounding the Haddam Neck Plant covering approximately forty three (43) surface acres FSS was completed.
Largely wooded or overgrown with brush, the areas consist of either hilly uplands or low-lying wetland areas.The HNP site maintains a reference coordinate system based on GPS coordinates using coordinates consistent with the Connecticut State Plane System. A benchmark was established in 2001 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 9521-0000 Survey Unit 9521-0000 (Southeast Pond) is designated as Class 3 and consists of 25,456 m 2 (6.30 acres) of uninhabited open land located approximately 0.24 miles from the reference coordinate system benchmark used at HNP. The area topography varies from flat areas overgrown with brush to rocky outcroppings to wooded sloping hills with steep grades. A small pond is contained in the interior of the survey unit.Some low-lying areas near the pond are marshy. Old stone walls presumably used to mark former property lines are evident along Cove Road and the northern edge of the pond. There are no structures within the survey unit. This survey unit is bounded on the north by Survey Area 9526; by Cove Road on the east; by the Discharge Canal on the south; and by a security fence and Survey Area 9522 on the west.The Canal Road crosses through the survey unit. Work activities to support the Independent Spent Fuel Storage Installation (ISFSI) Haul Road construction have occurred in the survey unit, especially on and along the Canal Road.Survey Unit 9527-0001 Survey Unit 9527-0001 (East Mountain Side) is designated as Class 2 and consists of approximately 8,600 m2 (2.13 acres) of wooded and wetland areas located approximately 0.1 miles from the reference coordinate system benchmark used at HNP. The survey unit is bounded by a fence 27 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 on the northern side, an unpaved road along the western side and a stone wall along the southern side. A Class 2 survey unit, 9527-0002, bounds this survey unit on the south. The survey unit comprises wooded terrain with some steep rock ledge and rock outcroppings within the interior.Survey Unit 9527-0002 Survey Unit 9527-0002 (East Mountain Side) is designated as Class 2 and consists of approximately 9,740 m 2 (2.41 acres) of wooded area located approximately 0.13 miles from the reference coordinate system benchmark used at HNP. The survey unit is bounded by a fence on the eastern and western sides, an unpaved road along the western side and a stone wall along the northern side. A Class 2 survey unit, 9527-0001, bounds this survey unit on the north. The survey unit comprises wooded terrain with some steep rock ledge and rock outcroppings within the interior.Survey Unit 9527-0003 Survey Unit 9527-0003 (East Mountain Side) is designated as Class 2 and consists of 8,200 m 2 (2.03 acres) of uninhabited open land located approximately 0.16 miles from the reference coordinate system benchmark used at IINP. A fence bounds the unit to the east, south and west. A Class 2 Survey Unit, 9527-0002 bounds the survey unit to the north. The survey unit comprises wooded terrain with some steep rock ledge and rock outcroppings within the interior.Survey Unit 9527-0004 Survey Unit 9527-0004 (East Mountain Side) is designated as Class 2 and consists of 3,500 m2 (0.86 acres) of uninhabited open land located approximately 0.10 miles from the reference coordinate system benchmark used at HNP. The survey unit is bounded by a fence on the southern side, a running trail along the northern side and a stone wall along the western side. A Class 3 survey unit, 9526-0000, bounds this survey unit on the south. The survey unit comprises wooded terrain with some steep rock ledge and rock outcroppings within the interior.
A stream runs through the interior of the survey unit, and includes waterfalls due to the steep terrain.Survey Unit 9528-0002 Survey Unit 9528-0002 (Southeast Mountainside) is designated as Class 2 and consists of 9,752 m2 (2.41 acres) of uninhabited open land located approximately 0.32 miles from the reference coordinate system benchmark used at HNP. The interior of the survey unit to the north and along Cove Road appears undisturbed as indicated by the overgrowth of surrounding brush. Old stone walls presumably used to mark former property lines are evident from Cove Road to about 0.1 miles in the 28 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 interior.
The area topography consists of overgrowth of brush and vegetation with a small wetlands area. There are no structures within the survey unit. The survey unit is bounded on the north by survey area 9528-0000; on the east by survey area 9528-0003; on the west by Cove Road;and on the south by the Discharge Canal.Survey Unit 9531-0000 Survey Unit 9531-0000 (Southern End of Peninsula) is designated as Class 3 and consists of 108,222 m 2 (26.8 acres) of uninhabited open land located approximately 0.77 miles from the reference coordinate system benchmark used at HNP. The area is mostly wetlands and wooded lowlands with large clumps of heavy brush. The topography of the southern portion of the peninsula is somewhat flat with sloping banks to the Discharge Canal and Connecticut River. The soil is mostly sand and the area is covered with dense grass or brush with some spots being heavily wooded. Survey Unit 9531-0000 is bounded on the east by the Discharge Canal, on the south and west by the Connecticut River, with a portion of Survey Area 9530 bounding the north perimeter.
A small pond is contained in the interior of the survey unit. An old roadway allows for access to the end of the peninsula.
3.3 Summary of Historical Radiological Data The site historical radiological data for IINP 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 surveys 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 7.15. 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 contaminate
[sic] the storm drain system;" Multiple waste gas tank rupture disc actuations in the 70's;29 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 1981;* Draining of the PAB 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;" Provide the basis for initial classification of areas;30 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006* 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 1OCFR50.75 (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 Contamination Issues at Haddam Neck" (Reference 7.43), dated March 26, 1998, to assure completeness of the historical data.31 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 7.44)." 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 Surveys were not performed for the Survey Units being submitted within the scope of this document.3.4 Conditions at the Time of Final Status Survey The majority of land areas discussed in this FSS Final Report are mostly wooded or open land areas. One survey area (9531) has been undergoing archaeological investigations that resulted in small test pits and trenches.Construction activities were 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 7.45) This included posting of the 32 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 heavily wooded 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 radionuclide identified in most of the samples was Cs-137, and, in a few areas, Co-60. For a majority of the samples, the concentrations of Cs-137 were below or at those concentrations determined from off-site locations as documented by Health Physics Technical Support Document (TSD)BCY-HP-0063, "Background Cs-137 Concentration in Soil." (Reference 7.46) The reported values of Cs-137 were not enough to warrant radiological soil remediation.
Cesium-137 deposition resulting from nuclear weapons testing fallout is thought to be the source of most of the Cs-137 encountered in samples collected in the outlands surrounding HNP. Geological deposition, regional concentrations and transport mechanisms are well documented and the subject of numerous publications and studies. However, as a conservative measure, Cs-137, resulting from fallout, was not subtracted from analytical results for quantitative evaluation to demonstrating compliance.
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 were false positives and were counted as positive detects because the criterion used at HNP was 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.33 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 During the FSS implementation, areas of interest were "scanned" with portable, hand-held radiation detection instruments.
Prior to scanning, background levels were determined and investigation levels set in accordance with Health Physics Technical Support Document BCY-HP-0081, "Scan MDC of Land Area using a 2-inch by 2-inch Sodium Iodide Detector" (Reference 7.47). Areas were then scanned for elevated readings.
When an elevated area was found, the area was marked and a sample was collected at that location unless otherwise denoted and explained in the FSS Release Record.Occasionally, during the scanning surveys, rock outcroppings would exhibit elevated activity above the investigation levels established by the sample plan. As suspected, pegmatite containing primordial radionuclides
-naturally occurring radioactive material (NORM) -was the cause of the elevated instrument readings.
Details on this occurrence are discussed further in Section 5.5 and are discussed in associated Survey Unit Release Records.3.6 Radiological Release Criteria The radiological release criteria is based on Title 1OCFR20, 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 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 to 25 mrem/yr.The DCGLs presented in Chapter 6 of the LTP were developed for exposures from three potential media, that is, residual radioactivity in soil, existing groundwater radioactivity, and additional future groundwater radioactivity from underground systems, structures or components containing residual radioactive material within the groundwater saturated zone in the area. The compliance equation provided in the LTP is based on meeting a total dose of 25 mrem/yr TEDE from all three media. Further agreements made with the State of Connecticut, Department of Environmental Protection, effectively reduce the release criterion to a total dose of less than or equal to 19 mrem/yr.HTotaiIHSoi-+-H1ExistingGW-+/-HgFutureGW (HNP LTP Equation 5-1)A reduction to the Base Case Soil DCGLs provided in Chapter 6 of the LTP must be performed to ensure compliance with the release criteria of 19 mrem/yr TEDE when all three pathways (soil, existing groundwater 34 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision I September, 2006 and future groundwater) are potentially present. Equation 1 showed the compliance formula for including the total dose from the three media.The reduced DCGL is called the Operational DCGL which is used in conjunction with the unity rule, or sum of fractions, when multiple radionuclides are present in sufficient quantities.
Inputting the values for existing groundwater and future groundwater dose (i.e., two (2) mrem/yr and zero (0) mrem/yr, from Reference 7.1) results in an allowable dose from soil of twenty-three (23) mrem/yr TEDE. However, to meet the allowable dose for soil and ensure compliance with the CTDEP release criteria for CY of nineteen (19) mrem/yr TEDE, this FSS plan assigns seventeen (17) mrem/yr TEDE as the Operational DCGL for soil, which is the criteria for demonstrating compliance under this FSS plan. Table 1 provides the Base Case Soil DCGLs and the Operational DCGLs for soil.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 might 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 18.1 qualified Health Physics Technicians to perform fieldwork, FSS Engineers to prepare the plan, generate maps, coordinate field activities and evaluate data. An off-site 35 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 laboratory would be needed to analyze the samples and provide quality radionuclide specific results." IDENTIFY THE DECISION Principal Study 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.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, 1OCFR50.75 (g) (1) files, and radiological surveys providing an indication of the potential for contamination.
Sampling and Analysis Methods to Meet the Data Requirements:
Soil samples were collected down to a depth of 15 cm (6 inches) in most cases, although a few FSS plans did require biased at-depth samples. 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.
Determining the Operational DCGL: Table 2-3 lists twenty radionuclides potentially present at the site.Derived Concentration Guideline Levels (DCGLs) were calculated for each of the radionuclides listed based on a limit of 25 mrem/yr dose limit. To calculate DCGLs, dose models were developed to relate levels of residual radioactivity to potential dose. The DCGLs presented in Table 2-1 were developed for exposures from three 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 (HTotal) from all three media, is not to exceed 25 mR/y. Note: The limit for HTotal is reduced to 19 mrem/yr to comply with CYAPCO's commitment to the 36 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 CTDEP.All but one survey unit (i.e., 9531-0000) covered by this FSS Final Report were considered impacted by existing groundwater radioactive contamination as the survey units were within the capture zone perimeter for an affected monitoring well. The dose contribution from the existing groundwater contamination, the second component of HNP LTP Equation 5-1, will be addressed later and will be included to show compliance with site unrestricted release criteria as required by the HNP LTP. All survey units were not considered impacted by future groundwater radioactive contamination, as there are no underground foundations or footings containing residual radioactive material within the groundwater saturated zone in the area. The dose contribution from future groundwater, the third component of HNP LTP Equation 5-1, is therefore zero.Once the dose pathways have been identified, the Operational DCGL was established.
Currently, guidance has been provided by Site Closure memo ISC 06-024, "Revised Target Operational DCGLs for CY", (Reference 7.1) and is dose pathway dependent.
The resulting Operational DCGL is equal to 15, 17 or 19 mrem/yr depending on the present and future groundwater dose limit reductions for a particular survey unit.It is important to note that several of the survey units submitted in this report demonstrate compliance at a 10 mrem/yr level. This was due the paucity of groundwater dose information available at the time of final status survey. The balance of the survey units 9527-0001 through 9527-0004 are updated in Revision 1 of this report to more clearly demonstrate compliance at a 17 mrem/yr level for soil dose.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.All 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.
37 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 Detectable Concentrations (MDCs) for soil samples were typically set to the dose equivalent of 1 mrem/yr.The HNP LTP specifies a required scanning coverage fraction of 0%to 100% based on FSS class. The fraction of scanning coverage was determined during the DQO process with the total amount, and location(s) based on the likelihood of finding elevated activity during FSS.All FSS 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 not applicable.
All survey units were either 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 1 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.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 of four conclusions shown in Table 4-1.38 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 (1) release criterion The average concentration is less than the Operational DCGL (1) but an individual sample exceeds Operational 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.Scanning and sampling in a survey unit was normally performed only during daylight and dry weather.Constraints:
The most common constraints were the weather, brush and undergrowth." 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." SPECIFY TOLERABLE LIMITS ON DECISION ERRORS The Null Hypothesis:
Residual radioactivity in the survey unit exceeds the release criteria.Type I Error: This is the cc error. This is the error associated with incorrectly concluding that the null hypothesis was rejected.
The HNP LTP has set the cc error at 0.05 (5%) unless prior approval is granted from the USNRC to use a less restrictive value. Therefore, a 39 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 value of 0.05 (5%) was used for survey planning and data assessment for FSS.Type II Error: This is the 03 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/a): 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 was conservative as it increased 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 7.22. 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 7.48) and the appropriate grid spacing for the assigned class (i.e. random or systematic).
Visual Sample Plan 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).Number of scan areas and location:
Scan survey areas locations were based on the conditions found during the area inspection or historic evaluation.
The amount of scan coverage was based on the potential for small areas of elevated radioactivity.
40 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 Number of samples for Quality Control: The number of quality control samples was usually 10% percent of the sample set. The locations for split samples was selected randomly using the Microsoft Excel RANDBETWEEN 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. For scan measurements, the investigation level is determined as a function of ambient.background level using guidance in accordance with Reference 7.47.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 design.4.2 Survey Unit Designation and Classification Procedure RPM 5.1-10, "Survey Unit Classification," (Reference 7.49)defines the decision process for classifying an area in accordance with the HNP LTP and MARSSIM. During the FSS of areas submitted for Phase III FSS Final Report no 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 7.46 and Reference 7.51 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.
During FSS area scanning, ambient backgrounds were determined and the"elevated" reading limit for that scan area was established by the technician.
Each Survey Unit Release Record discusses scan area readings (instrument readings for each scan area is enclosed with each release record in the appendixes).
Instrument backgrounds are discussed in the applicable procedure and in accordance with Reference 7.47.41 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 7.14.4.5 Survey Design 4.5.1 Determination of Number of Data Points The number of samples was determined in accordance with Reference 7.22. A summary of survey design data points is provided in Table 4-2.Table 4 Number of Surface Samples for FSS Survey Unit Survey Design Biased Investigation Samples Samples () Samples 9521-0000 15 7 4 9527-0001 15 3 9527-0002 15 2 4 9527-0003 15 2 1 9527-0004 15 2 16 9528-0002 15 9 _9531-0000 15 15 16 (1) The number of biased samples was determined during the DQO process and augmented as necessary by addendums to the FSS plan 4.5.2 Sample Locations Locations of the samples were determined using software Visual Sample Plan (VSP) in accordance with Reference 7.48. 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 7.52). The TSD contains documentation including a user's manual for VSP Version 2.0 and verification documentation.
VSP software imports a two (2) dimensional 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.42 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 For those locations where access was impractical (under standing water) or unsafe, the location was either moved within a reasonable distance from 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. Referred to by the FSS plan, this evaluation is documented in Reference 7.47. Detector sensitivities are also discussed in Section 5.7 of the HNP LTP.4.6.1 Detector Efficiencies The Eberline E-600 survey instrument coupled with the SPA-3 high sensitivity gamma detector was selected as the primary radiation detection instrumentation for FSS surveys at HNP.Efficiencies for the SPA-3 Sodium Iodide probe are demonstrated during calibration as the ability to respond as expected when exposed to a gamma radiation field from a NIST traceable Cs-137 source. If the response is within an acceptable range, then the detector is placed in service; otherwise, the instrument is considered "Out of Service" and sent for evaluation and repair.This method is described in procedure GGGR-R4206-003 RPM 4.2-14, "Calibration of the Eberline SPA-3 Smart Probe" (Reference 7.53).4.6.2 Detector Sensitivities Instrument DQOs include a verification of the ability of the survey instrument to detect the radiation(s) of interest relative to the Operational DCGL. DQOs established that the E-600 with the SPA-3 scintillation probe, operated in the data-logging, rate-meter mode, set to audio response, met the detection criteria needed to perform FSS surveys. Table 4-3 provides specifications for the SPA-3 detector.43 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 Table 4-3 -SPA-3 Technical Details and Specifications Application High sensitivity gamma measurements 2-inch diameter by 2-inch thick NaI(T1)Detector Type (5.1 centimeter x 5.1 centimeter)
Operating 1,000 volt nominal Voltage Dead Time 14 gs nominal Background
-1.2 Mcpm/mR/h Sensitivity (Cs- 137)Energy Range -60 keV to 2 MeV Operating
-22' to +140' F Temp (-30' to +60' C)Housing Aluminum body Connector CJ-1 2.63 inch diameter x 11.13 inch long (6.7centimeter x 28.3 centimeter)
Weight 3.4 lbs. (1.5 kg)Detector sensitivity, or the ability to detect radionuclides of interest at levels acceptable for FSS, is derived as a function of the application of the DQO process, from vendor specifications, instrument calibration, survey technique and a determination of background and Minimum Detectable Count Rate (MDCR).Unless noted otherwise in the Survey Unit Release Records, before performing FSS of land areas, a scanning investigation level was established for each sample location and judgmental scan area based upon the ambient background levels at the location.
The investigation level was determined using Reference 7.47, which provided the MDCR and investigation level relative to the ambient background count rate. The scanning investigation level was equal to the MDCR plus the ambient background count rate. The methodology was consistent with guidance provided in NUREG-1507, "Minimum Detectable Concentrations with Typical Radiation Survey Instruments for Various Contaminants and Field Conditions" (Reference 7.54).The background level was determined by holding the detector at arms length and at waist height near the scan location and the reading logged. The investigation level was determined and scanning was performed.
An instrument response above the investigation level required investigation and in most cases, 44 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 additional sampling.
Typical ambient background levels and corresponding investigation levels are provided in Table 4-4.Table 4-4 -Ambient Background Counts Rates, Associated MDCRs, and Investigation Levels Background (cpm) MZDCR (cpm) Investigation Level 2500 714 3214 3000 782 3782 3500 845 4345 4000 903 4903 4500 958 5458 5000 1010 6010 5500 1059 6559 6000 1106 7106 6500 1152 7652 7000 1195 8195 7500 1237 8737 8000 1278 9278 8500 1317 9817 9000 1355 10355 9500 1392 10892 10000 1428 11428 10500 1464 11964 11000 1498 12498 11500 1532 13032 12000 1565 13565 12500 1597 14097 13000 1629 14629 13500 1660 15160 14000 1690 15690 14500 1720 16220 15000 1749 16749 15500 1778 17278 16000 1807 17807 16500 1835 18335 17000 1862 18862 17500 1890 19390 18000 1916 19916 18500 1943 20443 19000 1969 20969 19500 1995 21495 20000 2020 22020 20500 2045 22545 21000 2070 23070 45 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase I11, Revision 1 September, 2006 1 Table 4-4 -Ambient Background Counts Rates, Associated MDCRs, and Investigation Levels Background (cpm) MDCR (cpm) Investigation Level 21500 2094 23594 22000 2119 24119 22500 2143 24643 23000 2166 25166 23500 2190 25690*24000 2213 26213 24500 2236 26736 25000 2259 27259 25500 2281 27781 26000 2303 28303 26500 2325 28825 27000 2347 29347 27500 2369 29869 28000 2390 30390 28500 2411 30911 29000 2433 31433 29500 2453 31953 30000 2474 32474 30500 2495 32995 31000 2515 33515 31500 2535 34035 32000 2555 34555 32500 2575 35075 33000 2595 35595 33500 2614 36114 34000 2634 36634 34500 2653 37153 35000 2672 37672 35500 2691 38191 36000 2710 38710 36500 2729 39229 37000 2748 39748 37500 2766 40266 38000 2785 40785 38500 2803 41303 39000 2821 41821 39500 2839 42339 40000 2857 42857 46 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 4.6.3 Instrument Maintenance and Control Control and accountability of survey instruments were maintained to assure the quality and prevent the loss of data. Health Physics Technicians performing field survey activities and assessing the data collected were trained in the use and control of the instruments applicable to the tasks they were performing.
Training consisted of reading required procedures and On-the-Job Training.The E-600 remained in the custody of assigned technicians, and positive control was maintained, until collected data had been downloaded.
Log sheets and other forms used to record field data remained in the custody of the responsible individual, and positive control was maintained, until the instrument was returned to secure storage. Procedure RPM 5.2-1, "Setup and Operation of the E-600 Digital Survey Instrument for Scoping, Characterization and Final Status Surveys," (Reference 7.55) provided details on the instrument for field use.4.6.4 Instrument Calibration Instruments were calibrated using NIST traceable sources using approved procedures and instructions.
Instrument calibration and repair history were documented for each instrument and probe.Instrument integrity and operation was checked prior to use and issue. Only trained and qualified personnel repaired, calibrated or tested FSS instrumentation.
Instrument response checks were performed prior to use, at the completion of the survey, and prior to data download.
An instrument failing a response check was removed from service. In addition, an investigation was performed to determine if collected data was corrupt. Instrument source and performance checks were documented for each instrument.
4.7 Survey Methodology 4.7.1 Scan Surveys The HNP LTP specifies the minimum amount of scanning required for each class (See Table 4-5). The total fraction of scanning coverage was determined for each survey unit during the DQO process with the amount, and location(s) based on the likelihood of finding elevated activity during FSS.47 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 Table 4-5 -Scan Coverage Survey Unit Classification Required Scanning Coverage Fraction Class 1 100%Class 2 10% to 100%Class 3 Judgmental Scan areas were walked down and marked out using flags, and the area staked out with GPS when possible.
The area was divided into manageable 1-meter wide strips with variable lengths depending on the size of the scan area and the location.
The strips are then mapped (flagged as a row 1-meter wide by the strip length long, and was scanned 100% of the available area. The instrument was operated in the rate meter mode with the audio response enabled. During the scan, the probe was positioned as close to the ground as possible and was moved at a scan speed of about 0.5 meters per second. Areas with elevated readings were marked and evaluated, and in most cases additional sampling was performed.
Table 4-6 provides a summary of the area scanned during FSS.Table 4-6 -Summary of Total Area Scanned Survey Area in Area Survy UScanned in Percentage Survey Unit Unit Square Classification Meters Square Scanned Meters 9521-0000 3 25,476 546 2.1 9527-0001 2 8,600 2,150 25 9527-0002 2 9,740 2,435 25 9527-0003 2 8,200 2,050 25 9527-0004 2 3,500 875 25 9528-0002 2 9,750 1043 11 9531-0000 3 108,221 988 0.91 For random and biased sample locations, the scan area for samples was a circle of one (1) meter radius around the sample flag. The instrument was operated in the rate meter mode with the audio response enabled. During the scan, the probe was positioned as close to the ground as possible and was moved at a scan speed of about 0.5 meters per second. When applicable, the sample location was moved, and the sample was collected, from the area exhibiting elevated readings.48 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 During the scanning, the technician recorded data in the Daily Survey Journal. This log documented field activities and other information pertaining to the FSS.4.7.2 Soil Sampling In accordance with the FSS plan and procedure RPM 5.1-3,"Collection of Sample Media for Final Status Survey" (Reference 7.56), the FSS technician collected surface soil or at depth samples in random, systematic, and biased locations.
Each sample location was documented on the Daily Survey Journal and, in some cases, the soil conditions and other observations were documented.
Chain of custody was used to maintain sample integrity.
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 7.23 establishes a method for evaluating QC split samples collected in support of FSS. QC split 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 7.57).A minimum of ten percent (10%) of the sample locations used in the FSS design were selected randomly using the Microsoft Excel"RANDBETWEEN" 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.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.49 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 7.25 provides guidance to Site Closure personnel to interpret survey results using the DQA process during the assessment phase of FSS. Although 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 DQA 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 were 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 evaluated raw data for problems or anomalies encountered during the FSSP activities (sample collection and analysis, handling and control, etc.) including the following:
- Recorded data;* Missing values;* Deviation from established procedure; and,* Analysis flags.50 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 1 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 Cs-137. The individual FSS Release Records covered by this FSS Final Report provide additional detail.Table 5-1 -Summary of Statistical Analysis for C s- 13 7 Maximum Mean Standard Survey Unit Class Concentration Concentration Deviation (pCilg) (pCilg) (pCilg)9521-0000 3 1.85E+00 6.42E-01 5.08E-01 9527-0001 2 1.48E+00 5.45E-01 3.14E-01 9527-0002 2 2.41E+00 8.85E-01 5.56E-01 9527-0003 2 1.83E+00 9.64E-01 4.66E-01 9527-0004 2 3.24E+00 1.24E+00 8.22E-01 9528-0002 2 7.92E-01 2.92E-01 2.85E-01 9531-0000 3 8.45E-01 3.30E-01 2.43E-01 5.2 Survey Data Verification and Validation Items supporting DQO sample design and data were completeness and consistency.
This includes: reviewed for* 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.Documentation, as listed, was reviewed to verify completeness and that it is legible:* Field and analytical results;* Chain-of-custodies;
- Daily Survey Journals;51 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006* 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 7.58). All the data for the survey units covered under this FSS 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 evaluated and determined to be non-applicable for survey areas covered under this FSS Final Report.52 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 (whether indicated by scanning or by sample result). 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 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.Another consideration is that, although verified, the sample reflects a mechanism for concentrating the radionuclide of concern, and additional sampling would only produce the same results. The engineer, through consensus, would take no further action and provide justification as needed. This situation was encountered during FSS in the wetlands and rocky slopes where a natural mechanism for concentrating Cs-137 exists.Researching this event shows that this type of occurrence is common and well documented in other regions of the United States.The "no-action" response is the most desirable result. In general, a no action response usually means that the sample plan was successful and the unit passes release criteria.
The assigned FSS Engineer will compile the data, re-verify the results and produce the Survey Unit Release Record as the product of the FSS.5.5 USNRC/lndependent Verification Team Findings The Environmental Survey and Site Assessment Program (ESSAP) of the Oak Ridge Institute for Science and Education (ORISE) performed independent confirmatory survey activities on selected open land survey units at the HNP site during the period of September 29 through October 1, 2003 and March 16 through 17, 2004. These surveys included three (3)of the seven (7) Phase III survey units.53 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 The confirmatory survey of the three (3) units is covered under ORISE Revised Final Report, "Confirmatory Survey of Open Land Area Survey Units at the Connecticut Yankee Haddam Neck Plan -Haddam, Connecticut" (Reference 7.59). The ORISE confirmatory survey activities included surface scans, soil sampling, and laboratory comparison analyses.According to the ORISE report, gamma scans of the open land areas identified several locations of elevated activity; but concluded that the source was from naturally occurring radioactive materials (NORM) within the granite outcrops in the surveyed area (refer to "Health Physics Technical Support Document Reference BCY-HP-0150, Investigation of Rock Outcropping Exhibiting Elevated Activity," (Reference 7.60) for additional details concerning this observation.
The ORISE report indicated that CYAPCO's off-site laboratory data were consistent and in agreement with their own analytic results.6.0
SUMMARY
The seven (7) survey units covered under this FSS Final Report have met the criteria of the applicable FSS plans. The FSS results provided herein address the dose component due to soil as provided in the HNP License Termination Plan (LTP) compliance Equation 5-1. The second component of HNP LTP Equation 5-1, dose contribution due to present groundwater has been determined to not exceed 2 mrem/yr in those survey units included in this submittal (Reference 7.1).All Phase III survey areas were not considered impacted by future groundwater radioactive contamination, as there are no foundations or footings containing residual radioactive material within the groundwater saturated zone in the area.The dose contribution from future groundwater, the third component of HNP LTP Equation 5-1, is therefore zero.
7.0 REFERENCES
7.1 Site Closure memo ISC 06-024, "Revised Target Operational DCGLs for CY" 7.2 Haddam Neck Plant License Termination Plan 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 54 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 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 GGGR-R5111-002, "Preparation of Final Status Survey Plans" (RPM 5.1-11)" 7.15 "Results of Scoping Surveys", September 1998 7.16 "Augmented Characterization Survey Report", January 1999 7.17 "Characterization Report", January 2000 7.18 "Historical Site Assessment Supplement" August 2001 7.19 GPP-GGGR-R5400-000, "Site Closure Training Program (RPM 5.4-00)" 7.20 GGGR-R5103-003, "Control & Accountability of Portable Survey Instruments for Scoping, Characterization and Final Status Surveys (RPM 5.1-4)" 7.21 GGGC-00001-004, "Work Plan and Inspection Record" 7.22 GGGR-R5112-001, "Determination of the Number of Surface and Subsurface Samples for FSS of Open Land Areas (RPM 5.1-12)" 7.23 GPP-GGGR-R5124-000, "Split Sample Assessment for Final Status Survey (RPM 5.1-24)" 7.24 GPP-GGGR-R51004-003, "Chain of Custody for Final Status Survey Samples (RPM 5.1-5)" 7.25 GGGR-R5123-000, "Data Quality Assessment (DQA), (RPM 5.1-23)" 55 Connecticut Yankee Atomic Power Company Haddam Neck Plant Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 7.26 "Quality Assurance Program for Haddam Nuclear Plant," (CYQAP)7.27 QSR-04-072-CY 7.28 QSR-04-073-CY 7.29 QSR-04-078-CY 7.30 CYAPCO, "Final Status Survey Program Assessment Report" June, 2004 7.31 Condition Report 04-0810 7.32 Condition Report 04-0811 7.33 CYAPCO Nuclear Safety Audit Report, CY-04-A09-01, "Final Site Survey (FSS)/License Termination Plan (LTP)," November, 2004 7.34 Condition Report CR 04-1298, "Failure to process timely License Basis Document Change Request (LBDCR) for the License Termination Plan (LTP) changes".7.35 QSR-05-009-CY 7.36 QSR-05-021-CY 7.37 QSR 06-001-CY 7.38 Self Assessment 05-01 "Final Status Survey Instrumentation" 7.39 Audit Report for CY Quality Assurance Audit CY-06-A05-01, "Final Status Survey (FSS)/License Termination Plan (LTP" 7.40 Post Shutdown Decommissioning Activities Report (PSDAR)7.41 Updated Final Safety Analysis Report (UFSAR)7.42 US NRC NUREG CR-5849 "Manual for Conducting Radiological Surveys in Support of License Termination" 7.43 "NRC Historical Review Team Report -Radiological Control and Area Contamination Issues at Haddam Neck" USNRC, dated March 26, 1998 7.44 CYAPCO Health Physics Department Technical Support Document BCY-HP-0078, "ALARA Evaluation of Soil Remediation in Support of Final Status Survey 7.45 24265-000-GPP-GGGR-R5116-002, "Area Preparation for Final Status Survey Activities (RPM 5.1-16)" 7.46 Health Physics Technical Support Document (TSD) BCY-HP-0063,"Background Cs-137 Concentration in Soil." 7.47 Health Physics Technical Support Document BCY-HP-0081, "Scan MDC of Land Areas using a 2-inch by 2-inch Sodium Iodide Detector." 7.48 GGGR-R5114-001, "Identifying and Marking Locations for Final Status Survey (RPM 5.1-14)".56 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision 1 September, 2006 7.49 GPP-GGGR-R51 10-001, "Survey Unit Classification (RPM 5.1-10)7.50 License Basis Document Change Request From (LBDCRF) #55 Initiated 2-12-06 7.51 EPRI Technical Report 1003030, "Determining Background Radiation Levels in Support of Decommissioning Nuclear Power Plants." 7.52 Health Physics Technical Support Document (TSD) BCY-HP-0079, "Use and Verification of Visual Sample Plan" 7.53 GGGR-R4206-003 RPM, "Calibration of the Eberline SPA-3 Smart Probe (RPM 4.2-14)" 7.54 NUREG-1507, "Minimum Detectable Concentrations with Typical Radiation Survey Instruments for Various Contaminants and Field Conditions" December 1997.7.55 GPP-GGGR-RPM 5.2-1, "Setup and Operation of the E-600 Digital Survey Instrument for Scoping, Characterization and Final Status Surveys," 7.56 GPP-GGGR-RPM5102-002, "Collection of Sample Media for Final Status Survey" 7.57 USNRC Inspection Manual, Inspection Procedure 84750, "Radioactive Waste Treatment and Effluent and Environmental Monitoring," March 1994.7T58 GPP-GGGR-R5121-001, "Applying the Sign Test (RPM 5.1-21)" 7.59 ORISE Revised Final Report, "Confirmatory Survey of Open Land Area Survey Units at the Connecticut Yankee Haddam Neck Plan -Haddam, Connecticut" 7.60 Health Physics Technical Support Document BCY-HP-0150,"Investigation of Rock Outcropping Exhibiting Elevated Activity," 8.0 Appendices Al Survey Unit Release Record 9521-0000, Southeast Pond A2 Survey Unit Release Record 9527-0001, East Mountain Side A3 Survey Unit Release Record 9527-0002, East Mountain Side A4 Survey Unit Release Record 9527-0003, East Mountain Side A5 Survey Unit Release Record 9527-0004, East Mountain Side A6 Survey Unit Release Record 9528-0002, Southeast Mountain Side 57 Connecticut Yankee Atomic Power Company Haddam Neck Plant Final Status Survey Final Report -Phase III, Revision I September, 2006 A7 Survey Unit Release Record 9531-0000, Southern End of Peninsula 58 Docket No. 50-213 CY-06-128 Attachment 2 Haddam Neck Plant Memorandum ISC-06-024, "Revised Target Operational DCGLs/Dose Tarlets for CY" September 2006 ISC 06-024 CONNECTICUT YANKEE ATOMIC POWER COMPANY HADDAM NECK PLANT 362 INJUN HOLLOW ROAD 9 EAST HAMPTON, CT 06424-3099 August 2, 2006 ISC 06-024 TO: File FROM: R. McGrath
SUBJECT:
Revised Target Operational DCGLs/Dose Targets for CY
Attachment:
ISC 04-049, Initial Target Operational DCGLs for CY The purpose of this memo is to revise the Target Operational Derived Concentration Guideline Levels (DCGLs) for use in Final Status Survey (FSS) design at CY. This revision is appropriate due to the additional information that has been collected since the attached memo was issued, such as: " An additional 20 months of groundwater sampling has been accomplished involving 10 sample rounds. During the 6 months since all remediations which had the significant potential to affect groundwater were completed, 6 sample rounds have been completed.
- All remediation, scanning and sampling have been completed for all structures to remain at CY at the time of license termination that have a significant potential for residual radioactivity.
This allows the completion of the Basement Fill Model calculations for these structures.
The remainder of this memo discusses the Operational DCGLs/Dose Targets to be used going forward in the design of FSSs to be conducted.
As the attached memo provides the background on the need and basis for the Operational DCGLs/Dose Targets, that information will not be repeated here unless it is revised.Background Per the NRC regulation and the CY LTP, "Dose Total" can be no more than 25 mrem/yr TEDE (plus ALARA) from all pathways.
This requirement applies at the time of removal of a survey area from the CY 10 CFR Part 50 license. Additionally, the Connecticut Department of Environmental Protection (CT DEP) in a letter dated November 20, 2002 adopted a radiological remediation standard of 19 mrem/yr TEDE (plus ALARA) to the average member of the critical group. Whereas the CT DEP standards are applicable under the Connecticut Property Transfer Act, they apply at the time of property transfer.
It should be noted that CY has reached an understanding with the CT DEP that the Page 1 of 4 ISC 06-024 Maximum Contaminant Levels (MCLs) defined by the US Environmental Protection Agency (US EPA) for groundwater contamination will be achieved at CY at the time of property transfer.Existing Groundwater As mentioned above, CY has collected a great deal of information since the completion of all known radiological remediations below the water table in late 2005. The sample data has indicated the following:
- The highest post-closure TEDE dose calculated for "existing groundwater" since December of 2005 was 1.4 mrem/yr (MW-1 37, Dec 2005). As of June of 2006, the calculated dose in this well is now approximately 0.75 mrem/yr. All other wells on site have exhibited a calculated dose of 0.8 mrem/yr or less since February of 2006.* At the time of property transfer, the sum of the MCL fractions for existing groundwater concentrations needs to be 1.0 or below to satisfy CT DEP requirements.
For H-3 and Sr-90, the MCL corresponds to a post-closure dose from existing groundwater of less than 0.8 mrem/yr. The MCL of 200 pCi/L for Cs-137 represents a fairly high post-closure existing groundwater dose of 11.6 mrem/yr. The Cs-1 37 dose at an "existing groundwater" target of 2 mrem/yr corresponds to 34.5 pCi/L. The highest Cs-1 37 concentration on site since December of 2005 has been less then half of this value (17 pCi/L in MW-1 37, December 2005). For the other radionuclides requiring monitoring, there have been no detections or very low or irregular detections that are of no significance from a post closure dose or MCL standpoint.
Based on the above, an existing groundwater dose target of 2 mrem/yr can be confidently established at this time.It should be noted that this dose target allows for additional margin at the time of release of all non-ISFSI area from the NRC license. As will be illustrated below, the various dose targets will be set so as to add up to 19 mrem/yr TEDE; the CT DEP limit. As the NRC release criteria is 25 mrem/yr, the dose target for existing groundwater could be raised for purposes of release from the NRC license to 8 mrem/yr should an unexpected increase occur.Future Groundwater As mentioned above, the basement fill model calculation has been completed for all structures expected to have significant levels of residual radioactivity.
The results of this calculation are that the highest calculated future groundwater dose is 1.6 mrem/yr (Containment/Fuel Building Calculation).
Allowing for a 20 % safety margin for any unexpected significantly contaminated concrete, the target dose for "future groundwater" is set at 2 mrem/yr.Page 2 of 4 ISC 06-024 Soil Having set the other two target dose values above, the soil target dose for each survey unit will be calculated by subtracting the dose targets for existing and or future groundwater when they apply for a survey unit. The actual soil target dose values for survey areas are determined below.1. Former RCA/Industrial Area: the CY LTP states that the area where both existing and future groundwater dose components could occur "includes the industrial area of the site". This area includes all the concrete to remain at the time of release of the non-ISFSI areas that has been shown to contain residual radioactivity.
Therefore, survey areas in this zone will include the existing and future groundwater dose contributions established above. For these areas, the Soil Target Dose is set at 15 mrem/yr (CT DEP Limit -Existing Groundwater
-Future Groundwater
= 19 2 = 15 mrem/yr).
The Survey Areas/Survey Units for which this applies are as follows: Survey Areas/Survey Units for Which 15 mrem/yr Soil Target Dose Applies 9302 9304 -All Units 9306 9312- All Survey Units 9313 9522 -Units 0005, 0006 & 0007 9801, 9802 2. There are survey areas/units that are potentially affected by existing groundwater, but contain no contaminated concrete to remain at survey area release. For these areas, the future groundwater dose component does not apply and the Soil Target Dose is set at 17 mrem/yr (CT DEP Limit -Existing Groundwater
= 19 -2 = 17 mrem/yr).
The Survey Areas/Survey Units for which this applies to are as follows: Survey AreaslSurvey Units for Which 17 mremlyr Soil Target Dose Applies 9106 -Unit 0001, 0002, 0003, 0004, & 0014 9512 9514 9520 -All Units 9521 9522 -Units 0001, 0002, 0003 & 0004 9527 -All Units 9528 -0000, 0002, & 0003 9530 -All Units 9803, 9804, 9805, 9807 Page 3 of 4 ISC 06-024 3. Since all other survey areas/units not listed in 1 and 2 above are located in land areas unimpacted by either existing or future groundwater dose components, all other survey areas/units may be designed to a Soil Target Dose of 19 mrem/yr.Note that remediation to lower levels may be required in areas that exhibit measurable concentrations of certain relatively mobile radionuclides.
This is due to the commitment to CT DEP to achieve the EPA MCLs as discussed above. H-3 and Sr-90 are the primary radionuclides to which this will apply. Sr-90 is relatively mobile and has a relatively low MCL. H-3 is extremely mobile and, therefore, small concentrations can have a large effect. After characterization has been performed and remediation or final status survey planning is in progress, the Site Closure Technical Support Manager (SCTSM) and/or the Groundwater Program Lead (GPL) should be consulted to review the characterization data. The consultation will determine the need for lower remediation target levels in order to facilitate continuing the achievement of the MCLs in the future.Approval Process for Exceeding Individual Operational DCGL/ Dose Target Values The Operational DCGLs/ Dose Targets for existing and future groundwater dose components include safety margin as previously mentioned.
There are also areas where existing groundwater dose has been shown to be much lower than 2 mrem/yr. As a result, there is some flexibility in the target values that can be set for individual DCGLs while maintaining compliance with the applicable regulations and requirements.
Considering the above, changes can be made to the Operational DCGL/ Dose Target Values with the approval of the FSS Manager. Use of higher values should be evaluated on a case-by-case basis, considering project economics.
The target level may be increased based on economic evaluations that consider the savings from reduced labor, waste disposal, and FSS costs.Please contact me with any questions on this memo.Cc: M. Marston J. Wagner C. Miller C. Newson B. Couture FSS Staff G. van Noordennen Page 4 of 4