ML20197D434
| ML20197D434 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 12/31/1997 |
| From: | YANKEE ATOMIC ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20197D431 | List: |
| References | |
| PROC-971231, NUDOCS 9712290055 | |
| Download: ML20197D434 (72) | |
Text
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b YANKEE NUCLEAR POWER STATION LICENSE TERMINATION PLAN Revision 1 i
December 1997 i
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Prepared By:
Yankee Atomic Electric Company 530 Main Street Hehon, Massachusetts 01740 O
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i YNPS LICEf4SE TERMINATION PLAN REVISION 1 TABLE OF CONTENTS ABBREVIATIONS. TERMS. AND UNITS TLO TLG Services,Inc.
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.YAEC Yankee Atomic Electric Company YNPS Yankee Nuclear Power Station
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YNPS LICENSE TERMINATION PLAN REVISION 1 l
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YNPS LICENSE TERMINATION PLAN REVISION t
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Samples of roofing material were collected from most buildings on site during 1996. These samples were analyzed for gamma emitting radionuclides. While 5 of the 20 samples contained low but detectable levels of radioactivity, only two samples from the east end of the Primary Auxiliary Building contained radioactivity in excess of the guideline values.
2.3.3 Activation Analyses Neutron activation of the Reactor Pressure Vessel (RPV), the Neutron Shield Tank, and the Bioshield wall was estimated analytically. Gamma ray transport analyses were performed that calculated neutron activation by isotope from neutron flux data, reactor operating history, and material properties of the individual components. The results of the analyses are shown in Tables 3.1-7 through 3.1-9 of the Pecommissioning Plan. The analyses showed that the water in the Neutron Shielu Tank provided adequate shielding to reduce the activation of the outer Neutron Shield Tank wall and the Bioshield wall by five to six orders of magnitude. With the RPV and Neutron Shield Tank removed, concrete core samples recently taken from the Bloshield wall will provide further information on the depth of neutron activation.
2.4 ENVIRONMENTAI. SURVEYS Environmental radiological investigations have included surveys for contamination in soll, asphalt, sediment, and groundwater, as well as the storm drain and leach field systems. Systematic sampling and monitoring (primarily of soil and asphalt) was performed during the scoping survey. Targeted sampling was then done as part of characterization surveys for all environmental media. This sampling was based on input from previous surveys, review cf historical plant records (summarized in Appendix B of the Decommissioning Plan), interviews with plant personnel, Radiological Environmental Monitoring Progrran (REMP) data, and aerial photos. These targeted surveys were expanded as necessary in an iterative fashion to determine the horizontal and vertical extent of any significant contamination that was found. Contamination levels in environmental media were compared to the guideline values for the 15 mrem / year residential scenario from Table B 2 of NUREG-1500. If a radionuclide was present on site and was not listed in Table B-2, guideline values were determined by the use of the RESRAD computer code (Reference 2-4). Environmental surveys are ongoing.
2.4.1 Determination of Background Radiation Values As a result of global fallout from atmospheric nuclear weapons tests, Cs-137 is a significant part of the ambient background in the northeastem United States, particularly in forest soils and richly organic sediment. In order to assign background values to various parts of the YNPS site for this fallout-related 2-3
REVISION 1 YNPS LICENSE TERMINATION PLAN Cs-137, in situ gamma spectroscopy measurements have been made and samples collected from reference locations. Analyses currently undenvay will determine the appropriate background values to be subtracted from fimal status sun ey rer.ults.
2.4.2 Surface Soil and Asphalt Surveys Surface contamination in surface soil and asphalt has been evaluated by the collection of soil grab samples, soil core samples, asphalt grab samples, and in situ measurements. Surface soil samples include soil, sod, stream sediment,:
i humus that is within the top 300 mm from the surface. Soil immediately under asphalt is considered surface soil. As part of the scoping and site characterization surveys, over 400 soil grab samples and over 110 asphalt grab samples have been collected. In situ gamma spectroscopy measurements have also been made at 140 locations with a high purity germanium detector (collimated to reduce on-site background radiation levels). Based on information collected as part of the preparation for final status surveys, a limited number of additional surface soil and asphalt samples, as well as in situ measurements, are planned for 1997.
Table 2-1 gives a summary of the characterization surveys done to date in each of the site areas shown on Figure 2-1. The primary radionuclides detected in soil on the YNPS site have been Co-60, Cs-137, and in limited areas, Ag-108m.
h Although site characterization surveys are ongoing, results of surface sampling to date indicate that most contamination is limited to approximately the top 150 mm of soil. Only the Outdoor Radioactive Materials S*orage Area does not currently meet the r ince soil guideline values for the conservative residential scenario of NUREG-1500.
2.4.3 Subsurface Soil Sampling and Gamma Logging in Open Land Areas Subsurface soil studies in open land areas were begun in 1993, documented in Section 3.1.4.2 of the Decommissioning Plan, and currently include data from 11 soil borings ranging in depth from 2.4 to 9.4 meters. These consist of 75 mm l
diameter continuous borings that were divided into multiple samples from 300 to 600 nun in length. Several of the borings were also used for the installation of groundwater observation wells, as described in Section 2.4.5. In addition to soil borings, several test pits were excavated with a backhoe to procure subsurface samples up to 2.1 meters deep. Borings and test pits were intentionally l
located at sites where contamination is known or suspected to be present below the surface. The locations of these wells, borings, and test pits are shown on Figure 2-2.
Results of analyses of soil samples are summarized in Table 2-2. For reference, g
2-4
YNPS LICENSE TFEMINATION PLAN REVISION 1 OP-8122 " Subsurface Soil Sampling and Monitoring Well Installation."
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DP-8123," Sample Chain of Custody."
DP-8124," Collection of Pond Sediment Samples for Site Characterization."
l 3-DP-9745, " Groundwater Level Measurement and Sample Collection in i
Observation Wells."
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YNPS LICENSE TERMINATION PLAN REVISION 1
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SECTION 3 IDENTIFICATION OF REMAINING DISMANTLEMENT ACTIVITIES 3.I INTRODUCTION As of April 1997, the majority of systems and components not required to suppon the storage of spent fuel have been dismantled and disposed ofin accordance with the Yankee Nuclear Power Station Decommissioning Plan and Final Safety Analysis Report (References 3-1 and 3 2). In addition, the Spent Fuel Pool and other systems associated with fuel storage have been electrically and mechanically isolated to create a Spent Fuel Pool " island" that will not be adversely impacted by ongoing decommissioning activities.
The current status of the systems, structures, and components described in the Final Safety Analysis Report is shown in Table 3 1. The purpose of this section is to identify the dismantlement and decontamination activities associated with the remaining systems, structures, and components at YNPS.
Decommissioning will be completed in three phases. The current phase consists of the removal of any remaining systems and components which do not support fuel storage or subsequent deconta.nination activities. After the removal of all spent fuel and Greater-Than Class-C (GTCC) waste from the Spent Fuel Pool (SFP), the second phase of decommissioning will involve the dismantlement and decontamination of the SFP and its supporting systems, structures, and components. In the final phase of decommissioning, the possession only license will be terminated.
3.2 REMAINING SYSTEMS, STRUCTURES, AND COMPONENTS NOT l
NECESSARY FOR SPENT FUEL STORAGE (PilASE 1)
The remaining systems and components listed below are not necessary to support spent fuel storage and will be dismantled and decontaminated in the current phase of decommissioning. Dismantlement and decontamination activities will be performed in accordance with the general considerations of Section 2.3 of the YNPS Decommissioning Plan and Section 200 of the FSAR. In many cases, only a part of the system will be removed, with the remaining portion maintained in service to e pport spent fuel storage.
Dismantlement activities will continue to be planned to ensure that there will be no adverse impact on spent fuel storage operations, Any applicable sections of the Decommissioning Plan and FSAR that are specific to a system or component are shown respectively in parentheses:
Portions of tS Radiation Monitoring System (Section 2.3.5.15; Section 215)
Vapor Container Ventilation and Purge System 'Section 2.3.5.16; Section 216)
Portions of the Fuel Handling System (Section 2.3.5.20, Section 220) p Original Plant Septic Tank and Piping v.
3-1
REVISION 1 YNPS LICENSE TERMINATION PLAN Waste Hold-Up Tank (Section 2.3.5.55; Section 225)
Portions of the Fire Protection and Detection System (Section 2.3.5.32; Section 232)
Vapor Container Polar Crane (Section 2.3.5.38; Section 238)
Yard Area Piping (buried piping from several different systems)
After the removal of systems and components from an area or building, contaminated concrete, steel, and other building materials will be decontaminated or removed in a manner consistent with Section 2.3 of the YNPS Decommissioning Plan. The structures listed below are not required to store spent fuel and will be decontaminated in the current stage of decommissioning. Any applicable sections of the Decommissioning Plan and FSAR that are specific to a structure are shown respectively in parentheses:
Vapor Container (Section 2.3.5.36; Section 236)
Reactor Support Structure (Section 2.3.5.37; Section 237)
Upper and Lower Pipe Chases (Section 2.3.5.41; Section 241)
Fuel Transfer Chute (Section 2.3.5.42; Section 242)
South, East, and West Walls ofIon Exchange Pit (Section 2.3.5.44; Section 244)
Primary Auxiliary Building (Section 2.3.5.48; Section 248)
Diesel Generator Building (Section 2.3.5.49; Section 249)
Waste Disposal Building (Section 2.3.5.50; Section 250)
Safe Shutdown Building (Section 2.3.5.51; Section 251) h Potentially Contaminated Area (PCA) Buildings 1 and 2 (SecM 2.3.5.52; Section 252)
Compactor Building (Section 2.3.5.53; Section 2W)
Final status surveys will be conducted according to Appendix A to verify that structures or open land areas not required for spent fuel storage meet the release criteria.
Independent verification of the results by the NRC will allow for the release of the individual surveyed structures and open land areas as non-radiologically controlled material available for conventional demolition and disposal. In order to facilitate remediation, structures may be released and demolished prior to remediating subfloor soils beneath the structures. Measures will be implemented as described in Section 4.1.7 of Appendix A to prevent recontamination of surveyed areas prior to final license temiination.
3.3 SYSTEMS, STRUCTURES, AND COMPONENTS ASSOCIATED WITH STORAGE OF SPENT FUEL IN TIIE SPENT FUEL POOL (PHASE 2)
Aner the spent fuel and GTCC waste have beer. removed from the Spent Fuel Pool, the remaining components of the systems listed below will be dismantled and decontaminated in accordance with Section 2.3 of the Decommissioning Plan and Section O
3-2
O FINAL STATUS SURVEY PLAN FOR SITE RELEASE A
Yankee Nuclear Power Station O
Revision 1 1
December 1997 I
Prepared By:
Yankee Atomic Electric Company 580 Main Street Bolton, Massachusetts 01740 0
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
TABLE OF CONTENTS Section lille Eage EX ECUTIVE SUMM ARY.......................................... A-vii 1.0 HISTORICAL D ACKGROUND........................................ A 1 2.0 S ITE IN FO RM ATION............................................... A-3 2.1 Site Description..........................
....................A-3 2.2 Site Conditions at Time of Final Status Survey...................... A-3 3.0 FINAL STATUS SURVEY OVERVIEW................................. A-7 3.1 Survey Objectives............................................. A-7 3.2 Scope of the Final Status Survey.................................. A-7 3.3 Identity of Contaminants........................................ A-8 3.3.1 Building Surfaces and Systems.............................. A-8 3.3.2 Soil and Ground wate r..................................... A-8 3.4 Determination of Guideline Values................................ A-9 3.4.1 Surface Contamination Guideline Values...................... A-9 3.4.2 Soil. Sediment and Bulk Material Activity Guideline Values..... A-11 3.5 Organization and Responsibilities................................ A-11 3.6 Qu ality Assurance............................................ A-l l 3.6.1 Instrumentation Selection, Calibration and Operation............ A-12 3.6.2 Survey Documentation...................
...............A-12 3.6.3 Quality Control - Replicate Surveys......................... A-12 3.6.4 Written Procedures...................................... A-12 1
3.6.5 Chain of Cu stody....................................... A-13 1
3.6.6 Records Management.................................... A 13 1
3.6.7 Independent Review of Survey Results....................... A-13 i
'I 8 Access Control of Surveyed Areas and Systems................ A-13 1
3.t.9 Control of Vendor-Supplied Services......
.................A-13 1
3.7 Trai n i n g.................................................... A-1 3 1
3.8 Laboratory Services........................................... A-14 3.9 S c h e d ul e.................................................. A-14 3.10 Final Status Survey Reporting................................... A-15 4.0 SURVE Y PLAN AND PROCEDURES................................. A-17 4.1 G e neral S e rvey Plan........................................... A-17 4.1.1 History File Preparation.................................. A-17 4.1.2 Initial Area Classification................................. A-18 4.1.3 Wal kdown............................................ A - 19 4.1.4 Tumover for Final Status Survey........................... A-20 A-il
YNPS FINAL STATUS SURVEY PLAN REVISION 1 n
TABLE OF CONTENTS
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(Continued)
Section Tjds PJige 4.1.5 In vestigation........................................... A-20 1
4.1.6 Reclassification........................................ A-21 4.1.7 Access Control Measures................................. A-21 4.2 Initial Area Classification of the YNPS Site......................... A-21 1
4.3 Measurement Frequency....................................... A-23 4.3.1 S t ru ct u re s............................................. A-2 3 4.3.2 Pl ant S yste ms.......................................... A-25 4.3.3 Open land Area ;........................................ A-26 4.4 S u rvey M e thods.............................................. A-2 8 1
4.4.1 Scan S urveys.......................................... A-28 1
4.4.2 Surface Contamination Measurements....................... A-29 4.4.3 Exposure Rate Measurements.............................. A-29 4.4.4 Soll and Water Sampling................................. A-29 I
4.4.5 Special Measurements and Samples......................... A-30 4.4.6 Sa.pling for Hard to Detect Nuclides (HTDN)................ A-31 1
4.5 Background Level Determinations................................ A-32 (3')
4.5.1 Total Surface Beta-Gamma Measurements.................... A-32 1
4.5.2 Removable Surface Beta-Gamma Measurements............... A-33 4.5.3 Soil and Sediment Radionuclide Measurements................ A-33 4.5.4 Gamma Exposure Rate Measurements....................... A-33 4.5.5 Specialized Measurements................................ A-33 1
4.5.6 Verification of Background Measurement Population............ A-34 4.6 I n stru mentation.............................................. A-34 4.6.1 Minimum Detectable Concentration Calculation................ A-34 I
4.6.2 Detector Sensitivity..................................... A-35 4.6.3 Calibration and Maintenance.............................. A-36 4.7 Survey Areas, Units, Locations and Points.......................... A-36 4.7.1 Survey Areas and Survey Units............................ A-36 4.7.2 Survey Locations and Survey Points......................... A-36 1
5.0 DATA PROCESSING AND INTERPRETATION......................... A-40 1
5.1 Conversion of Measurements to Reporting Units..................... A-40 1
5.1.1 Total Surface Centamination.............................. A-40 1
5.1.2 Removable Surface Contamination,,........................ A-40 1
5.1.3 Exposure Rate......................................... A-41 1
5.1.4 Soil and other Bulk Samples............................... A-41 5.2 Comparison with Administrative Action Levels...................... A-41 I
5.2.1 Mean and Standard Deviation.............................. A-42 I
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5.2.2 Ele vatea r.reas of Contamination........................... A-43 l
A-iii
YNPS FINAL STATUS SURVEY PLAN REVISION 1 TABLE OF CONTENTS (Continued)
Section Title Eage 5.2.3 Calculation of the 95% Confidence Interval of the Mean......... A-44 1
5.2.4 Processing of Investigation Survey Data...................... A-45 1
5.3 ALARA An alysis............................................. A-4 5 l
6.0 FINAL STATUS SURVEY REPORTS.................................. A-49 I
6.1 Topical Outli ne.............................................. A-4 9 I
6.2 Reporting of Survey Findings................................... A-49 I
6.2.1 Detail Data Reporting for Each Survey Area.................. A-49 I
6.2.2 Summary Data Reporting for Each Survey Area.
............ A -4 9 6.3 Final TEDE Evaluation........................................ A-50 1
7.0 REFE R EN C ES.................................................... A 5 1 1
7.1 Sun cy Plan References........................................ A-51 1
7.2 Proce d u re Re fere n ces.......................................... A-5 2 1
8.0 G LOS S A R Y...................................................... A-5 3 I
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YNPS FINAL STATUS SURVEY PLAN REVISION 1 i
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' Title P. age '
3.1 Surface Contamination Limits...................................... A-16
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3 4.1_
Final Status Survey Instrument Summary............................. A-37 1
4.2 -
Nominal Measurement Detection Sensitivities.......................... A-38 1
5.1 Summary of Action Levels for Reclassification and Remediation........... A-47 l
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YNPS :1NAL STATUS SURVEY PLAN REVISION 1 4
O LIST OF FIGURES i
Figure Iitic P_ age 2.1 Facility Layout.................................................. A-4 2.2 Radiation Control Art s (RCA)...................................... A-5 2.3 Initial Classification of '.
9.c. Site................................... A.6 4.1 Survey Area Classification Process.................................. A-39 I
5.1 Interpreting and Comparing Survey Data with Guideline Values............ A-48 I
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A vi
- YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
EXECUTIVE
SUMMARY
This document describes the r.ethods to be used by the Yankee Atomic Electric Company (Y/.EC) to demonstrate that radiation an( radioactive contamination levels at the Yankee Nuclear Power Station (YNPS) have been reduced to levels below criteria established for unrestricted mse. The site-specific release criteria presented in this plan I
are consistent with the criteria identified in the NRC Site Decommissioning Management l
Plan (SDMP) Action Plan of April 16,1992 (57 FR 13389), and therefore comply with 1
10 CFR 20.1401(b). This plan has been developed in accordance with the YNPS Final
'I S:.fety Analysis Report (FSAR) which incorporates the YNPS Decommissioning Plan.
This plan is in' ended to provide the basis for the implementing procedures governing the I
conduct of the fmal status survey. The methods described have been detived from regulatory guidance, specifically Regulatory Guide 1.86 " Termination of Operating Licenses for Nuclear Reactors" (Reference 1), Draft NUREG/CR-5849 " Manual for Conducting Radiological Surveys in Support of License Termination" (Reference 2) and
- Draft NUREG-1500, " Working Draft Regulatory Guide on Release Criteria for Decommissioning: NRC Staff's Draft for Comment" (Reference 3). Recent reactor facility decommissioning experience at the Fort St. Vrain Nuclear Station and the Shoreham Nuclear Power Station were also incorporated as appropriate.
The site will be divided into one of three types of survey areas: structures, systems or open land areas. These areas will then be classified as Affected or Unaffected based upon the area's radiological history. Survey packages will then be generated that define the survey methodology and intensity, based upon its classification. After collection, radiological data in a survey area will be analyzed and the results compared to the release criteria. These survey areas are the basic entities for data analysis. Every survey area on site must meet the release criteria with a 95% confidence level. This plan also describes the methods used to determine a survey instrument's response to unaffected building materials and soils for the purposes of subtracting background. It also describes the management controls over all aspects of the project which will ensure that the Plan is implemented properly.
The YNPS Final Status Survey Plan is part of the License Termination Plan which is considered a supplement to the FS AR in accordance with 10CFR50.82(a)(9)(i).
Therefore, revisions to this plan may be implemented without prior NRC approval provided the changes do not:
violate the criteria of Section 1.3 of the License Termination Plan, reduce the required survey frequency for a specific classification of survey area, a
increase the action levels for reclassification or remediation, or a
A-vii
REVISION 1 YNPS FINAL STATUS SURVEY PLAN affect the methodology for statistical treatment of survey data in a manner which
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reduces the confidence that the site meets the criteria for unrestricted use.
For the definitions of terminology used in the final status survey plan, please refer to Section 8.0, " Glossary."
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- YNPS FINAL STATUS SUP.VEY PLAN REVISION 1 1.0 HISTORICAL DACKGROUND Yankee' Nuclear Power Station (YNPS) achieved initial criticality in 1960 and began commere 4l operations in 1961. The Nuclear Steam Supply System was a four loop pressurized water reactor designed by Westinghouse Electric Corporation. The original thermal power design limit of 485 MWt was upgraded to 600 MWt in 1963. The Turbine Generator, also designed by Westinghouse, was rated to produce 185 MWe.
On February 26,1992, the Yankee Atomic Electric Company (YAEC) Board of -
Directors decided to cease power operations permanently at YNPS. This decision was based on the following factors:
Economic analyses indicated that shutdown of the plant before expiration of its Nuclear Regulatory Commission (NRC) operating license in July 2000 could produce a substantial savings to the electricity purchasers.
l Significant regulatory uncertainty associated with the tiining and cost of the completion of the NRC's review of the integrity of the YNPS Reactor Pressure Vessel.
J p
On August 5,1992, tie NRC amended the YNPS Facility Operating License (DPR-3) to Q
a possession only steis. Combined with other amendments and program changes, this formed the basis of 6 Decommissioning Plan. In December 1993. the plan was submitted by YAEC in accordance with the iequirements of 10 CFR 50.82(a), which required the submittal of a proposed decommissioning plan within two years of the permanent cessation of operations. The Decommissioning Plan also incorporated the Spent Fuel Management Plan required by 10 CFR 50.54(bb). The Decommissioning Plan was approved on February 14,1995. Due to subsequent litigation, the NRC suspended its approval of the Plan in October 1995; the Plan was finally re-approved on October 28, M 16.
As required by a commitment to the NRC, the Decommissioning Plan was incorporated into the June 1995 revision of the YNPS Final Safety Analysis Report (FSAR). Under the most recent revision of 10 CFR 50.82, an approved decommissioning plan is considered to be the licenseds post-shutdown decommissioning activities report (PSDAR) For YNPS, the terms " Decommissioning Plan" and "PSDAR" may be used in:erchangeably.
As of May 1997, the majority of the systems and components not required to support the storage of spent fuel have been dismantled and disposed of off-site in accordance with the YNPS Decommissioning Plan and FSAR. The Main Coolant System has been removed, including the Steam Generators, Pressurizer, and large diameter piping.
The Reactor Pressure Vessel has ';:en removed from containment and shipped to the
_ m_
Barnwell low level waste facility in an NRC-approved transportation cask. Structural A-1
YNPS FINAL STATUS SURVEY PLAN REVISION 1 9
decontamination work has begun in the Ion Exchange Pit and Waste Disposal Building following the clean-out of systems and components from these areas. The Spent Fuel Pool and other systems associated with fuel storage have been electrically and mechanically isolated to create a Spent Fuel Pool " island" that will not be adversely impacted by ongoing decommissioning activities. Radiological characterization of YNPS has been ongoing since 1992 and involves survey of systems, structures, and the environment.
Title 10CFR50.82(a)(9)(ii) requires that detailed plans for a final status survey be submitted as part of a License Termination Plan. This survey will be performed to ensure that the site, including any rernaining stmetures, meets the unrestricted release criteria in order to support termination of the Part 50 License. This Final Status Survey Plan describes the method for conducting the final status survey. Independent verification of survey results will be implemented through the NRC.
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A-2
YNPS FINAL STATUS SURVEY PLAN REVISION 1
['N 2.0 ;
SITE INFORMATION 2.1
- Site Description YNPS is located in the Berkshire Hills of Franklin County on a 2200 acre site along the Deerfield River in the towns of Rowe and Monroe Bridge, Massachusetts. About 10 acres of the site were developed for plant use. The site is at the bottom of a deep valley along the river at the southeast corner of Sherman Reservoir. The area surrounding the site is mostly wooded with very steep slopes on both sides of the Deerfield River. The hills on either side of the site rise about 1000 feet above the river level within one mile and extend from 12 miles nortS to 8 miles south southeast of the site. Sherman Reservoir served as the source of cooling water for the plant.
Data on the levels of radiation and radioactive material in the environs have been S
- collected as part of the annual Radiological Environmental Monitoring Program (REMP). The REMP will be continued throughout decommissioning.
Figures 2,1 and 2.2 show the layout of the overall facility and the Radiation Control Area
-(RCA), respectively.
2.2 Site Conditions at Time of Final Status Survey At the time of final status survey, the structures will be largely intact. To date, essentially all contaminated systems and components not supporting the storage of spent fuel have been removed from the site. The remaining contaminated systems and structures will be dismantled or decontaminated prior to initiation of the survey in those areas. -With spent fuel still in the Spent Fuel Pool, and contingent on having a low enough background radiation level, a final status survey will be completed on structures that do not support Spent Fuel Pool operation. A final status survey will be completed on the remaining structures after fuel is removed from the Spent Fuel Pool. If the fuel is transferred to a dry cask storage facility, a fm' al status survey will be performed on that 1
facility after the fuel is transferred offsite.
A-3
YNPS FINAL STATUS SURVEY PLAN REVISION I Kev to Features in Ficure 2.1 (Facility Layout Manh
- 01. Vapor Containct i1.Pnmary Auxiliary Building
- 02. Turbme Buildmg
- 12. Fue! Storage
- 03. Service Buddmg 13.lon Exchange Pit w-
- 04. Wareho.ase
- 14. Compsetor Building
- 05. Senenwell House
- 15. Waste Das Building u
N 06 Discharge Sawture
- 16. PCA W ouse
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- 07. Cate liouse
- 17. PCA Storage Building No, t
- 08. Switchyard
- 11. PCA Storage Buildmg No. 2
- 09. Training Center
- 19. Pole Barn
- 10. Diesel Generator Budding
- 20. Safe Shutdown System Building
- 21. East Storm Drain Outfall d.*l 64 ~.
, Shemen Pond...
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YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
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I Initial Classification of YNPS Site A-6 o
YNPS FINAL STurUS SURVEY PLAN REVISION 1
(
3.0 FINAL STATUS SURVEY OVERVIEW 3.1 Survey Objectives The final status survey is designed to demonstrate that lleensed radioactive materials have been removed from Yankee Nuclear Power Station (YNPS) facilities and property to the extent that residual levels of radioactive contamination ar * -low site-specific l
release criteria approved by the NRC. The site-specific re! ease enteria presented in this I
plan are consistent with the criteria identified in the NRC Site Decommissioning i
Management Plan (SDMP) Action Plan of April 16,1992 (57 FR 13389), and therefore I
comply with 10 CFR 20.1401(b). The YNPS site release criteria are as follows:
I Surface contamination must not exceed the values presented in Table 1 of Regulatory Guide 1.86 for average, maximum and removable contamination.
These limits have been adjusted, as described in this Plan, for hard to detect radionuclides.
Exposure rates from gamma emitting radionuclides, created as a result of reactor operation and located in soil and activated materials including concrete, components, and structures must not exceed an average 5 pR per hour above
(]
natural background measured one meter from the surface with a maximum of V
10 pR per hour at any point of measurement.
The Total Effective Dose Equivalent (TEDE) to the average member of the critical population group from residual contamination must be maintained below 15 mrem per year. ALARA principles will be used to reduce the residual levels of radioactivity on-site commensuras with the minimization of total risk. (See Section 4 of the License Termination Plan)
The contamination of groundwater and surface water as the result of site work must not exceed the Environmental Protection Agency regulation 40CFR Part 141, National Primary Drinking Water Standards for radioactivity.
3.2 Scope of the Final Status Survey The final status survey will include all structures, surfaces and systems identified as contaminated or potentially contaminated. The survey will include:
Surveys within the Radiation Control Area (RCA), including pavement, soil, groundwater, and structures such as the Vapor Container, PCA Warehouse, and Primary Auxiliary, Spent Fuel Storage, Waste Disposal, and Compactor Buildings.
f d
A-7
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
e Areas outside the RCA but within the 'wner Controlled Fence including pavement, soil, groundwater, and seccc try side structures such as the Turbine and Service Buildings and office areas.
Stmetures, pavement, soil, sediment, groundwater, and surface water outside the l
Owner Controlled Fence, not to include those areas identified as "non-impacted" (see Section 4.0).
3.3 Identity of Contaminants 3.3.1 Building Surfaces and Systems Residual contamination on plant piping and building surfaces is the result of the deposition of fission and activation products. Radioactivity found in the bioshield concrete is the result of contamination and neutron activation. During plant operation, many samples were taken from process and waste streams to determine radionuclide distributions. Prior to and during the scoping and characterization surveys, additional samples of process pipes and smears were obtained to determine the contamination radionuclide distributions. In addition, an analysis was performed to estimate radioactivity levels and radionuclide distributions in the reactor vessel, neutron shield tank and bioshield concrete. A surmary of the analyses of the contaminated and activated materials was presented in the YNPS Decommissioning Plan. (Reference 4, Section 3.1)
Three radionuclides, Fe-55, Ni-63 and Co-60, comprise approximately 98 percent of the radioactivity in the structures and systems. The predomir. ant beta-gamma I
emitter in these areas is Co-60 (Cs-137 is also present as a beta-gamma emitter, I
however it comprises less than 2% of the total radioactivity). Although the i
Decommissioning Plan provided radionuclide distributions for the reactor vessel and neutron shield tank, they will have been removed at the time of final status survey. Only a portion of the bioshield concrete vall will remain. Based upon the neutron activation analyses, four radionuclides, H-3, Fe-55, Co-60 and Eu 152, comprised approximately 97 percent of the radioactivity remaining in the activated bioshield concrete (as of January 1994). Of these, Co-60 and Eu-152 I
are the predominant beta-gamma emitters. As the plant dismantlement and I
decontamination continues, additional samples will be analyzed to verify and correct, if necessary, the radionuclide distributions in the remaining structures and systems.
3.3.2 Soil and Groundwater Surface soil has been sampled and analyzed for radionuclides. The predominant plant-related, beta-gamma emitting radionuclides that have been detected are i
Co-60, Cs-137, and in some areas, Ag-10Sm. These radionuclides have been i
A-8
YNPS FINAL STAWS SURVEY PLAN REVISION 1 p]
(
sporadically detected in the top six inches (15 cm) of on-site soil. Other radionuclides that have been detected to a lesser degree are Cs-134 and Mn-54.
1 Groundwater samples have been collected and analyzed for beta and gamma emitting radionuclides The primary contaminant is H-3, which has been found in monitoring wells located between the Ion Exchange Pit and Sherman Spring.
The maximum H-3 radioactivity concentration detected during decommissioning was 8,000 pCi/l.' This value is well below the 40CFR141.16 limit of 20,000 pCi/1. H-3 concentrations in groundwater will be monitored throughout the dismantlement and decontamination process.
3.4 Determination of Guideline Values The contamination levels of all structures, systems and open land areas remaining on site at the time of the final status survey will be compared to guideline values (GLVs).
Guideline values are those residual radioactivity levels that equate to the site release criteria for that particular pathway or measurement. The values to be used at YNPS are described in the following sections.
3A.1 Surface Contamination Guideline Values The surface contamination limits to be used for beta and gamma emitters (excluding H-3, Fe-55 and Ni-63), as specified in Table 1 of Regulatory Guide 2
1.86 and Table 3.1 of this plan are 5,000 dpm/100 cm average,15,000 dpm/
.100 cm maximum, and 1,000 dpm/100 cm' removable. In addition to these, 2
2 YAEC will use the following for H-3, Fe-55 and Ni-63: 200,000 dpm/100 cm 2
2 average,600,000 dpm/100 cm maximum, and 40,000 dpm/100 cm removable (see Table 3.1).
The surface contamination limits for H-3 and Fe-55 were applied at the decommissioning projects at Fort St. Vrain Nuclear Station (FSV) and Shoreham Nuclear Power Station, and theirjustification was provided in SECY-94-145 (Reference 5). YABC provided the average and maximum limits in response (Reference 6) to an NRC request for additional information following the submittal of the YNPS Decommissioning Plan. The increase in the total surface contantination limits, as described in SECY-94-145, would make the risk from
. the H-3 and Fe-55 similar to the risk from other radionuclides in Table 1 of Regulatory Guide 1.86.
p.
v A-9
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
The removable contamination limit for H-3 and Fe-55 has been set by YAEC to 20% of the average contamination limit, or 40,000 dpm/100 cm'. This limit is consistent with the other radionuclides in Table 1 of.R.G.1.86 and is based on the NRC's Safety Evaluation (Reference 7) of FSV's request to raise the removable contamination level to this limit.
Since Ni 63 comprises a significant fraction of the radionuclide inventory at YNPS (15 to 50%), and because its risk is comparable to that of Fe-55, YAEC will use the same average, maximum and removable surface contamination limits as for Fe-55 and H-3.
The site specific GLVs for removable and average surface contamination will be calculaMd using Equation 3.1 (derived from Equation A-2 in Draft NUREG/CR-5849, Appendix A):
F (3,1)
GLV =
' f f
f' L + - 2_
_n_
G, G
G,,
2 l
(
h where:
Guideline Value, i.e., the acceptable level of residual surface GLV
=
contamination for radionuclides normally dete-red during field measuc-ment Fraction of the total activity contributed by each radionuclide f,
=
Surface contamination limit for each radionuclide G,
=
Detectable radionuclide fraction.
F
=
.Affected Area Guideline Values: For affected survey areas, GLVs will be based upon previoudy determined radionuclide distributions for specific areas. For all other areas, where the radionuclide distribution has not been determined, the most conservative distribution, resulting in the lowest GLV of those specified areas, will be used. The distributions will be based on all of the radionuclides identified in composite samples from the specific areas, collected both during power operation and during decommissioning. If new radionuclide distribution data is obtained during the completion of decommissioning, and determined to be more appropriate for use, the GLVs may be re-evaluated and altered during the course of the final status survey.
A-10 J
YNPS MNAL STATUS SURVEY PLAN REVISION 1 Total surface and removable contamination limits ("G" in Equation 3.1) will be taken from the " average" and " removable" columns of TWe 3.1, respectively.
The maximum surface contamination limit is set at three times ti e average surface contamination GLV.
Unaffected Area Guideline Values Plant-relateo radionuclides re not expected to be present in unaffected areas. However, if any non-background rdioactivity is found in these areas, it will be assumed that its source was plant-related.
Therefore, the GLV for unaffected aeas will also be based on the most conservative distribution found in affected areas and will be the same as the GLV for non-specific affected areas.
3.4.2 Soll, Sediment and Bulk Material Activity Guideline Values GLVs for surface, subsurface and subfloor soil, sediment and bulk materials will be the concentration per unit mass of radionuclides that would lead to a TEDE of 15 mrem during a period of one year. These GLVs will be determined by use of I
the RESRAD (Reference 8) or D&D Screen (Reference 11) computer codes using I
conservative site-specific input parameters or parameters from NUREG-5512 I
(Reference 12). GLVs will be also be taken from Table B-2 (Residential I
g Scenario) of NUREG-1500 (Reference 3) if these values are more conservative.
I (j
Average concentrations above background for radionuclides in soil, sediment, and I
bulk materials will be compared against these GLVs as described in Section 5.0.
I Where more than one radionuclide is present, the sum of the ratios of each radionuclide concentration to its respective GLV should not exceed unity.
3.5 Organization and Responsibilities Final statas survey plan development and implementation will be performed 'uy Duke l
Engineering & Services personnel and supplemented by contractor personnel. All survey I
personnel will be qualified and trained in accordance with approved YNPS procedures.
Key position descriptions delineating responsibilities and interfaces have been developed and described by administrative procedure AP-8800. (Procedure Reference 1) 3.6 Quality Assurance The Decommissioning Quality Assurance Plan is based on the equirements of 10CFR50,
- Appendix B as they apply to decommissioning activities, and is discussed in Section 514 of the YNPS FSAR, This plan will be applied to the activities of the final status survey.
For all radiological analyses performed by the Duke Engineering & Services l
Environmental Labcratory, the Laboratory's Quality Assurance Plan will be applicable.
Examples of the QA program application are described in the subsections that follow.
O
.d A-11
' YNPS FINAL STATUS SURVEY PLAN REVISION I 3.6.1 Instrumentation Selection, Calibration and Operation Selection and use of instrumentation will ensure that sensitivities are sufficient to detect radionuclides at the minimum detection requirements specified in Section 4.6, and will assure the validity of the survey data. Instrument calibration will be performed either under approved written procedures using calibration sources traceable to the National Institute of Standards and Technology (NIST),
or by qualified vendors providing results traceable to NIST. Issuance, control, and operation of all survey instrumentation will be established by procedures.
3.6.2 Survey Documentation Each final status survey measurement will be identified by date, instrument, location, type of measurement, and mode of instrument operation.
3.6.3 Quality Control-Replicate Surveys For stmetures and systems, QC ieplicate measurements will consist of resurveys of 5% of randomly selected survey areas.
QC surface contamination and exposure rate measurements will be compared to the original measurements and if the same conclusions are reached without any additional exceptions the QC survey will be accepted as satisfactory. (Procedure References 9 and 11)
For open land areas, replicate QC surface contamination and exposure rate measurements will be treated the same as described above for structures and systems. For soil, water and sediment samples, QC sampling will consist of field blanks, blind duplicate samples and third party analyses from each open land survey area. Field blanks and/or blind duplicate samples are not applicable to certain sample types, such as asphalt or rubble.
If QC replicate measurements or sample analyses fall outside of their acceptance criteria, a documented investigation is iequired which may result in a resurvey or resampling.
3.6.4 : Written Procedures All final status survey tasks which are essential to survey data quality will be implemented and controlled by procedure. As appropriate, dry runs and mockups will be performed to test principle procedures and methods prior to -
implementation in the field.
O A-12
YNPS FINAL STATUS SURVEY PLAN REVISION 1 g.
i 3.6.5 Chain of Custody
- YNPS procedures will establish responsibility for custody of samples between the point of measurement or collection until fm' al results are obtained. When custody is transferred (e.g., when samples are sent off-site to another lab for analysis), a chain of :ustody form will accompany the sample for tracking purposes.
3.6.6 Records Management Generation, handling and storage of the original final status survey design and data packages will be controlled by approved procedures.
3.6.7 Independent Revie'w of Survey Results Randomly selected survey packages from survey areas will be independently reviewed by Duke Engineering & Services Quality Assurance Services to ensure I
that the survey results are documented in accordance with approved procedures.
3.6.8 Access Control of Surveyed Areas and Systems Administrative and physical controls for access to surveyed areas will be p) established to preclude the possibility of contamination subsequent to completion s
- of the final status survey. See Section 4.1.7 for additional information.
3.6.9 ' Control of Vendor Supplied Services Quality-related services, such as instrunient calibration and laboratory sample analysis, will be procured only from qualified vendors whose internal quality assurance activities are subject to audit in accordance with the Decommissioning Quality Assurance Plan.
3.7 Training 4
Qualification and training requirements have been established within the framework of the YNPS FSAR. Before assignment to the final status survey, technicians will receive training in the following:
- ~
Overview and objectives of the final status survey plan, Procedures governing the conduct of the final status survey, o
Operation of the appropriate field and laboratory instrumentation used in the final g
status survey, and A
A-13 l
I
.~
YNPS FINAL STATUS SURVEY PLAN REVISION 1 s
Collection of final status survey measurements and samples.
' The extent of training and qualifications will be commensurate with ti.e education, -
experience and proficiency of the individual and the scope, complexity and nature of the activity. - Records of training, including testing to demonstrate qualification, will be -
b 1
ma nta ned in accordance with established procedures.
i i
3.8 Laboratory Sen' ices The _YNPS n.dioanaly:ical programs are administered by the Radiation Protection and Chemistry Department in accordance with written procedures and an approved quality assurance program. On-site laboratory radioanalytical capabilities will be utilized to support the final status survey. Current on-site capabilities include gamma spectroscopy (llPGe), liquid scintillation, and gas proportional counting. Off-site laboratory sample analysis will be provided by the Duke Engineering & Services Environmental Laboratory I
or procured from other qualified vendors.
3.9 Sched The final status survey will be carried out in several phases (see Figure 1-1 of the i
License Termination Plan). The first phaec will occur while spent fuel is stored in the i
Spent Fuel Pool. It will encompass the entire site, excluding the Spent Fuel Pool, its h
supporting systems, structures and components, and a suitable buffer area. Throughout all phases, all completed areas will be controlled to prevent recontamination from decommissioning activities or the subsequent operation or decommissioning of the Spent Fuel Pool. The second phase of the final status survey will proceed after fuel is removed from the Spent Fuel Pool. The second phase of the final status survey will encompass
- the Spent Fuel Pool, its supporting systems, structures and components, and the previously-defined buffer area. If the fuelis transferred to an on-site dry cask storage facility, the final status survey following decommissioning of the storage facility will be covered via a supplement to the Final Status Survey Report.
Prior to completion of each phase, individual buildings or survey areas will be made available for independent verification of their radiological status. Upon completion of each major phase, records will be compiled, and an interim report will be prepared.
Upon official acceptance of the radiological status by the NRC, the surveyed structures and open land areas will be released and available for conventional demolition and
' disposal as non-radiological material.
O
- A-14 y-
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l YNPS FINAL STATUS SURVEY PLAN -
REVISION 1
.3.10 Final Status Survey Reporting Upon completion of each survey phase, an interim report may be submitted to NRC. At the completion of the entire decommissioning project, a final report will be prepared. All reports will be written to meet the intent of Regulatory Guide 1.86 for final status survey reporting, and will follow the guidance of Draft NUREG/CR-5849 regarding content and format. The interim and final reports are described in Section 6.0, " Final Status Survey Reports."
i i
6 O
J V
1 4
O A-15
YNPS FINAL STATUS SURVEY PLAN 1 REVISION 1 1
TAB 1] 3.1 Surface Contamination Limits 6
NUCLIDE :
AVERAGE' MAXIMUM -
REMOVABLE' U-nat, U 235,U 238 5,000 dpm a /100 cm 15,000 dpm a /100 cm' 1,000 dpm a /100 cm' 2
associated decay products Transt ranics, Ra-226, Ra-228, 100 dpm /100 cm' 300 dpm /100 cm' 20 dpm /100 cm' Th-230.Th-228 Pa-231, Ac-227,1 125,1 129
Ra-223, Ra 224, U-232, 1 126,I 151,1 133 H-3, Fe 55 Ni-63 200,000 dpm /100 cm' 600,000 dpm /100 cm' 40,000 dpm /100 cm' 2
2 Beta-gamma emitters 5,000 dpm /100 cm' 15,000 dpm /100 cm 1,000 dpm /100 cm (nuclides with decay modes other than alpha emission or spontaneous fission) except St-90 and others noted above.
Notes L
- n.
Measurements of average contamination levels should not be averaged over more than I square meter. For objects of less surface area, the average should be derived for each object.
I 8
b.
The maximum contamination level applies to an area of not more than 100 cm.
c.
- When removable contamination on objects of less surface area is determined, the pertinent levels should be reduced proportionally and the entire surface should be wiped.
l l
i o
O A-16 h
1.,
e
~ YNPS FINAL SILTUS SURVEY PLAN--
REVISION I~
V 4.0 SURVE Y PLAN AND PROCEDURES 4.1
' General Survey Plan The design approach of the YNPS fm' al status survey is affected by the final cor figuration of the facility, i.e., with most systems removed and structures largely' intact. The majority of the survey effort will occur in areas where radioactive materials
- we.e used or handled, such as the Vapor Container, Spent Fuel Building, Waste Disposal Building, Primary Auxiliary Building, and Yard Area.
= Three categories or types of survey areas have been established, including:
Structures, to include building interiors and exteriors, and the exterior surfaces of
- a plant systems,
. Plant systems, to include the interior surfaces of process piping and ventilation e
duct work, and Open land areas, to include soil, subfloor soil, sediment and groundwater, f3 For a discussion of survey an:as, se Section 4.7.
b Due to the large scope of the final status survey and th'e requirement that some survey activities be conducted in parallel with decommissioning work, a systematic approach is necessary. The final status survey planning and implementation process for each survey area will therefore involve, in addition to the actual survey activities discussed in the plan, each of the following activities, as applicable:
History file preparation e
e Initial classification e
Walkdown e-Turnover for final status survey (affected survey areas only)
Investigation,if required e
Reclassification,if required e
' Access control measures These steps are described in the following sections.
- 4.1.1 History File Preparation The history file will be a compilation of relevant operational and decommissio_ning data in a standardized format. The purpose of tHs process is to
-f ^
provide a substantive basis for the survey area classification, and hence the level i
of intensity of the final status survey. The history file will contain:
-A-17
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
The survey area description Operating history which could affect radiological status Summarized scoping and site characterization data A summary of radiological surveys performed during decommissioning Other relevant information 4.1.2 Initial Area Classification All areas of the YNPS site (including structures, plant systems and open land areas) will not have the same potential for the presence of residual contamination and therefore will not require the same level of survey coverage to achieve an acceptable level of confidence that an area satisfies the established release limits.
Therefore, to provide an overall planning basis for the final natus survey, the site has been initially classified into affected and unaffected areas, using the criteria given below and in Figure 4.1.
Initial classification of site areas was based on data provided in the YNPS Decommissioning Plan, subsequent site characterization data, history of radioactive materials involvement or potential for contamination of the survey area, recommendations by YNPS personnel knowledgeable of the fncility conditions, and any applicable survey data. Data from operational surveys done in support of decommissioning, routine surveillances, and any other applicable survey data may be used to change the initial classification of any individual survey area,if necessary, prior to the commencement of the final status survey in that survey area. The site breakdown and classifications are controlled by administrative procedure AP-8801 (Procedure Reference 2).
Areas are classified as follows:
Affected Areas: Affected Areas are those areas that have potential radioactive contamination based on plant operating history. They are also those areas, and where appropriate, the areas immediately surrounding or adjacent to them, that have known radioactive contamination (based on past or preliminary radiological surveys) due to one oi more of the following activities in the areas: 1) the use or storage of radioactive materials; 2) spills or other unusual occurrences that could have resulted in the spread of contamination; or 3) the burial of radioactive material. Any area that has been previously remediated will also be classified as an Affected Area.
Areas which are expected to have radioactive contamination existing at average levels in excess of 25% of the average total surface contamination, or soil guideline values, or greater than the Minimum Detectable Concentration (MDC) for the equipment used to perform the survey, whichever is larger, will be classified as Affected Areas.
A-18
~
YNPS FINAL STATUS SURVEY PLAN ~
REVISION 1
-Q
-U To allow a more concentrated survey effort in those areas most likely to be.
- contaminated, Affected Areas within a room or building will be further subdivided into Suspect Affected and Non-Suspect Affected Survey Units, as follows:
e-Suspect Affected Survev Units: The designation assigned to floor and wall surfaces below two meters within an Affected Area. Also, the designation assigned to all additional surfaces if there is reason to believe that there was licensed material present, unless it meets the criteria for a Non Suspect Affected Survey Unit.
Npn Susnect Affected Survev Units: The designation assigned to ceiling and wall surfaces above two meters within an Affected Area, where it is not expected that radioactive materials exist at average levels in excess of 25% of the average total surface contamination guideline values, or the MDC for the equipment used to perform the survey, whichever is larger.
This designation is based on engineering judgement, in consideration of operational history, characterization data, operational surveys performed in support of decommissioning, and routine surveillances, p
Unaffected Areas: These areas have a low potential for radioactive contaminadon, based on a knowledge of site history and previous survey information. Average measurements for average total surface contamination, and for average concentrations of radionuclides in soil or asphalt are expected to be less than 25% of the applicable guideline value or less than the MDC for the equipment used to perform the survey, whichever is larger Previous remediation precludes a survey area from being initially classified as unaffected.
Non-Imnacted Areas: Those areas of YNPS property that are outside of unaffected areas will be classified as non-impacted and will not be surveyed.
These areas have an insignificant potential for residual contamination.
(Reference 9) 4.1.3 Walkdown The principal objective of the walkdown is to assess the physical scope of the survey area. For systems, it will include a review of system flow diagrams and piping drawings, and a physical walkdown of the system. Structures and open land areas will also be walked down. The walkdown is best completed when the final configuration is known, usually near or after completion of decommissioning activities.
n A~-19 e
YNPS FINAL STATUS SURVEY PLAN REVISION 1 Specific requirements will be identified for accessing the survey area and obtaining support functions necessary to conduct the final status surveys, such as scaffolding, interference removal, and electrical tagout. Safety concerns such as access to confined spaces, high walls, and ceilings will be identified.
4.1.4 Turnover for Final Status Survey Prior to acceptance of a survey area for the final status survey, a number of conditions must be satisfied. These include:
Decommissioning activities having the potential to contaminate the survey area must be completed.
All tools and equipment not required to perform the survey must be removed, and housekeeping and area cleanup must be completed.
Decontamination activities in the survey area must be completed.
Final operational radiological surveys must b: completed in affected areas to ensure that no additional remediation is necessary and will consist of:
1.
Scan surveys to ensure that surface contamination is within the FSS total surface contamination limits.
2.
Smear surveys to ensure that the removable surface contamination is within the FSS removable surface contamination limits.
Access control or other measures to prevent recontamination must be implemented.
4.1.5 Investigation When an administrative action level is reached, an investigation is performed to confirm the initial final status survey measurement, and if verified to exceed action levels, to define the bounds of the elevated activity. Depending on the results of the investigation, the survey unit may require no action, remediation, and/or reclassification and resurvey. The administrative action levels for such action may be found in Table 5.1. Specific instructions for the processing of data following an investigation survey are included in Section 5.2.4.
O A-20
YNPS FINAL STATUS SURVEY PLAN REVISION 1 '
rk,y) 4.1.6 Reclassification ~-
Based on information obtained during final status survey activities, it may be necessary to reclassify certain survey units to ensure that the measurement frequency is appropriate for the contamination potential. Following reclassification, the newly classified survey unit will be re-surveyed under the appropriate survey requirements for that area. The existing final status survey measurements may be included with the additional survey data. Administrative -
action levels for reclassification are found in Table 5.1.
4.1.7 Access Control Measures Since all decommissioning activities will not be completed prior to the start of final status survey, measures will be implemented to protect survey areas from contamination during and subsequent to the final status survey. In all cases, decommissioning activities creating a potential for the spread of contamination must be completed within each survey area prior to the final status survey.
Additionally, decommissioning activities which create a potential for the spread of contamination to adjacent survey areas will be evaluated and controlled.
p Upon commencement oithe final status survey for survey areas where there is a 1
potential for contaminvion, implementation of one or more of the following control measures will be required:
Personnel training, Installation of barriers to control access to surveyed areas, Installation of postings requiring personnel to perform contamination monitoring prior to surveyed area access, Locking of entrances to surveyed areas of the facility, Installation of tamper-evident labels.
Controls will be implemented through procedure AP-8810 (Procedure i
Reference 10).
l s
4.2 '
Initial Area Classification of the YNPS Site i
The following areas on site have been initially classified as Affected Areas:
The interior surfaces of any remaining structures within the currently defined w/
Radiological Control Area (RCA)(see Figure 2.2), including the primary side A-21
YNPS FINAL STATUS SURVEY PLAN REVISION 1 instrumentation lab, counting rooms, primary side chemistry lab, contaminated sink and shower areas, north and south decontamination rooms, RCA machine shop, PC change room and the controlled side of the RP control point. The exterior surfaces of any systems in this area will also be classified as affected.
The interior surfaces of the Turbine Building, Front Office Building, original Service Building and Service Building Addition.
The PAB roof, all exterior surfaces of the Spent Fuel Pool Building, and the Vapor Container exterior surface below the equipment hatch.
A small activated area on the top center of the exterior surface of the Vapor Container.
All open land areas within the RCA.
A 10-meter wide buffer zone around the chain link fence surrounding the outdoor portions of the RCA.
The small section oflandscaped area bordered on the east by the west wall of the turbine building, on the south by the RCA fenceline, on the west by pavement, and on the north by the driveway leading to the overhead door on the west wall of the turbine building.
A 10-meter wide area from the east storm drain outfall to the Sherman Pond shoreline. This area will also include the sediment in a 10 meter radius semi-circle directly b-low the east storm drain outfall.
The stream-bed sediment from the point of the West Storm Drain Outfall to the Deerfield River.
Both the operable and inoperable plant septic systems.
The following areas have been initially classified as Unaffected Areas:
Any areas inside the Owner Controlled Area Fence not classified as Affected.
The exterior surfaces of structures not previously classified as Affected.
e A 20-meter wide buffer zone outside the Owner Controlled Area fence, and a 20-meter wide buffer zone outside of Affected Areas which are beyond the fence, where possible.
The interior surfaces of the Visitor Center (Furlon House), and Training Center.
h A-22
~ _ _. -
4 4
YNPS FINAL STATUS SURVEY PLAN REVISION 1:
O
_t i
V
- e' Parking lots The south end of Sherman Pond, within an approximate 200 meter radius of the
_I e
circulating water discharge structure.
1 These large areas will be subdivided into survey areas. Ifjustified by survey data or other information, ;he initial classification of an individual survey area may be changed in recordance with AP-8801 (Procedure Reference 2) prior to the commencement of the final status survey in that survey area.
- Prior to the commencement of the final status survey, the interior surfaces of any remaining systems will be subdivided into survey areas as necessary, and will be classified at that time.
All areas of the YNPS site that have not been classified as Affected or Unaffected have been classified as Non-Impacted. These areas will not be surveyed.
-4.3
- Measurement Frequency
- Measurement frequencies, or the physical spacing of samples and measurements, are A
selected to allow for a concentrated survey effort in those areas most likely to be d
ccataminated or activated, taking into account the type and size of the survey unit.
Measurement locations distributed throughout a survey unit will be documented in I
accordance with written final status survey procedures. The mearurement frequency for I
each area type is described below.
4.3.1 Structures Suspect Affected Survey Units: The final status survey of Suspect Affected Survey Units will include:
A scan survey of 100% of the accessible surface area.
e
. NOTE:
The scan survey may be performed at the time of survey unit turnover.
Total surface contamination (fixed point) measurements, as follows:
For areas s 30 square meters, a minimum of 30 measurement locations; For areas > 30 square meters, a minimum of one measurement location for each one square meter.
A-23
YNPS FINAL STATUS SURVEY PLAN REVISION 1 0'
Removable contamination (smears) will be obtained at locations where the total surface contamination measurement MDC or result is greater than the removable contamination limit.
Exposure rate measurements will be taken only on activated concrete, structures or components at a frequency of at least one measurement per 4 square meters.
In general, these areas will be gridded into one square meter grids, and the measurements will be taken at the center of grid blocks.
Non-Susnect Affected Survey Units: The final status survey of Non-Suspect Affected Sun'ey Units will include:
A scan survey at least 10% of the accessible surface area of the survey unit.
NOTE:
The scan survey may be performed at the time of sur ey unit turnover.
Total surface contamination (fixed point) measurements, as follows:
For areas s 600 squar, meters, a minimum of 30 measurement locations; For areas > 600 square meters, a minimum of one measurement location for each 20 square meters.
Removable contamination (smears) will be obtained at locations where the total surface contamination measurement MDC or resu'.: is greater than the removable contamination limit.
In general, these areas will not be gridded. Measurement locations will be distributed throughout the survey unit. In addition, some measurement locations will be selected from locations most likely to accumulate contamination.
Unaffected Surver Units: The final status survey of Unaffected Survey Units will include:
A scan survey of an a ea around each survey location so that the total area scanned is at least 10% of the accessible surface area of the survey unit.
Total surface contamination (fixed point) measurements on floors and walls below two meters, as follows:
A-24
YNPS FINAL STATUS SURVEl' PLAN REVISION 1 A
For areas s 1500 square meters, a minimum of 30 measurement locations; For areas > 1500 square meters, a mmimum of one measurement location for each 50 square meters.
e Removable contamination (smears) will be obtained at locations where the total surface contamination measurement MDC or result is greater than the
. re.novable contamination limit.
' In general, these areas will not be gridde'. Measurement locations will be --
d distributed throughout the survey unit and will be documented.
The final status survey of all building exteriors not previously classified as affected will be done in accordance with the protocol established for unaffected building surfaces.
4.3.2 Plant Systems Affected Plant Systems: The final status survey of the interior surfaces of affected plant systems will include:
0'd A scan survey of the accessible surfaces at each survey location.
e e
A minimum of 30 survey locations, as allowed by system size, to include a minimum of 30 measurements of total surface contamination within each survey area.
e Removable contamination (smears) will be obtained at locations where the total surface contamination measurement MDC or result is greater than the removable contamination limit.
Measurement locations will be selected from locations where contamination is most likely to accumulate. If appropriate, sampling and analysis of scale and sediment will be perfonned.
Unaffected Plant Systems: The final' status survey of the interior surfaces of unaffected plant systems will include:
A scan survey in the immediate vicinity of the total surface contamination location.
A minimum of 10 survey locations, as allowed by system size, to include
(
a minimum of 30 measurements of total surface contamination within
,'A each survey area.
A-25 l.
l
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
e -
Removable contamination (smears) will be obtained at locaticas where the total surface contamination measurement MDC or result is greater than the removable contamination limit.
Measurement locations will be selected from locations where contamination is most likely to accumulate. If appropriate, sampling and analysis of scale and sediment will be perfonned.
4.3.3 Open land Areas Affected Onen land Areas Without Paved Surfaces: The final status survey of affected open land areas without paved surfaces will include:
A scan survey of 100% of the accessible surface area.
Surface soil samples (15 centimeters deep) as follows:
For areas s 750 square meters, a minimum of 30 survey points; For areas > 750 square meters, a minimum of 4 survey points for each 100 square meters.
Exposure rate measurements taken at one meter from the surface at the location of each soil sample.
These areas will normally be gridded into 10 x 10 meter grids. Samples and measurements will be taken systematically within those grids.
Affected Open Lnnd Areas With Paved Surfaces: The final status survey of I
affected open land areas with paved surfaces will melude:
A scan survey of 100% of the accessible surface area.
Total surface contamination (fixed point) measurements, as follows:
For areas s 30 square meters, a minimum of 30 survey points; For areas > 30 square meters, a minirnum of one survey point for each one square meter.
In general, these areas will be gridded into one square meter grids, and the measurements will be taken at the center of grid blocks.
O A-26
YNPS FINAL STATUS SURVEY PIAN REVISION 1 O
Pavem::'it samples and surface soll samples (15 centimeters deep, beneath e
the pavement) as follows:
For areas s 375 square meters, a minimum of 30 survey points; For areas > 375 square meters, a minimum of 8 survey points for each 100 square meters.
t Exposure rate measurements taken at one meter from the surface at the location of tach soll/ pavement sample.
Samples and measurements will be taken systematically within those grids.
UnmNected Onen land Areas: The final status survey of both paved and unpaved surfaces in Unaffected Areas will include:
A scan survey of an area around each survey location so that the totai area e
scanned is at least 10% of the accessible surface area of the survey unit.
i Surface soil samples (15 centimeters deep) and exposure rate l
e measurements, and for paved surfaces, pavement samples and total surface contamination (fixed point) measurements, as follows:
For areas s 37,500,quare meters, a minimum of 30 survey points; For areas > 37,500 square meters, a minimum of one survey point for each 1,250 square meters.
In general these areas will not be gridded, although survey points will be documented.
r ANected Subnoor Areas With Floors Removed: The final status survey of affected subfloor areas with floors removed will include:
A scan survey of 100% of the accessible surface area.
Soil samples (15 centimeters deep) as follows:
For areas s 750 square meters, a minimum of 30 survey points; P
For areas > 750 square meters, a minimum of 4 survey points for each 100 square meters.
f A-27
YNI'S FINA! STATUS SURVEY PI,AN REVISION 1 O
Exposure rate measurements taken at one meter from the surface at the location of each soil sample.
These areas will nonnally be gridded. Samples and measurements will be taken systematically within those grids.
Affected Subiloor Areas With Floors intact: The final status survey of affected subfloor areas with floors intact will include:
Soil samples (15 centimeters deep) as follows:
For areas s 375 square meters, a minimum of 30 survey points; For areas > 375 square meters, a minimum of 8 survey points for each 100 square meters.
In general, these areas will be gridded, and the samples will be taken systematically within those grids.
Groundwater and Surface Water: A single yroundwater sauple will be I
collected as part of the final status survey in any survey unit where an operable groundwater observation well is located. A single representative surface water I
grab sample will be collected as part of the final status survey in any survey unit where a permanent surface water source exists.
4.4 Survey Methods 4.4.1 Senu Surveys Scan surveys will be perfonned to screen surface areas to identify the presence of any locations of elevated contamination in order to search for areas above the release limits and to detect localized areas above the rnaximum release limit. The scarming methods (instmment and survey technique) for surface contamination measurements will normally be designed to detect less than 75% of the average total surface contamination release limits. If an area of elevated contamination is identified during the scan of a survey unit, the location will be marked and included as a par; of the total surface contamination measurements.
O A-28
YNPS MNAL STATUS SURVEY PLAN REYlSION 1 4.4.2 Surface C9ntamination Measuremchts Surface contamination measurements will be taken at discrete mer.surement j
locations and at frequencies which are based on the classification of the survey unit. Typically only a total surface contranination measurement will be taken at each location.
t Before final status surveys are initiated, turnover surveys are performed by l
operational Radiation Protection Department personnel to verify that the measurement results are within the final status survey limits for removable and 3
total surface contamination. Final statur survey total surface contamination measurements will detect both removable and fixed contamination. If the total surface contamination results are less than the removable contamination limit, additional removable contamination measurements (smears) will not be made. If the total surface contamination results are greater than the removable surface contamination limits or the MDC of the measurement is greater than the removable contamination limit, additional removable surface contamination n.:asurements will be taken.
4.4.3 Exposure Rate Measurements Og Exposure rate measurements will be obtained at discrete locations which are based on the classification of the sr vey unit. Exposure rate measurements will and structures and in open land areas.
only be taken on activated compo e
Measurements will be taken at or..
.. from surfaces.
Exposure rates frcm infinite plane sources can be derived from data in NUREG-1500. The derived exposure rate from Co-60 in the NUREG was benchmarked with a commercially available computer code and found to be comparable. Various realistic geometries such as equipment rooms and large areas like the Turbine Deck at YNPS were evaluated to determine exposure rates from surface contamination. Assuming uniform contamination on the room surfaces and using the expected radionuclide distribution as input, the calculated exposure rate was much less than 5 pR/h. Non uniform contamination was also evaluated and found to be much less than 5 pR/h. Therefore, exposure rates are not necessary where the only source of residual contamination is surface contamination.
4.4.4 Soll and Water Sampling.
I Surface soil grab samples will generally be collected to a depth of 15 centimeters
. at discrete locations, and at frequencies which are based on the classification of g
the survey unit. Sampling at greater depths will be d,ne in areas where site Q
characterization or other information indicates potential contaWnation at depths A-29
YNPS l'INAL STATUS SURVEY I'LAN REVISION 1 O
greater than 15 centimeters. Soil samples will be analyzed for gamma-emmitting I
radionuclides.
I I
A single water grab sample will be collected from each observation well or i
permanent source of surface water in a survey unit at the time of the final status I
survey of that unit. To demonstrate compliance with 40 CFR 141, water samples I
will be analyzed for 11-3, Sr 90, and gamma-emmitting radionuclides.
I 4.4.5 Special Measurements and Samples Samnline of Miscellaneous Loose Mnterial Samples of loose paint, tank sediment, sewage sludge, roofing material, concrete and other bulk materials will be collected for laboratory analysis as part of biased sampling and measurements. Such samples may be collected in drain receptacles, sumps, and other catchments in affected areas. Selected storm drain catchments will be sampled in accessible locations on the site. These samples will be quantitatively analyzed by gamma spectrosecpy for principal gamma emitting radionuclides and the results compared to the applicable guideline value.
Embedded Pinine Surveys Measurements will be made to dernonstrate that normally inaccessible piping remaining at the time of the final status survey (e.g., embedded piping)is below the guideline values for surface contamination. This will include but not be limited to the ut.e of calibrated detectors extended into piping runs in a controlled manner and the use of data acquisition equipment to document the measurements.
The detectors that may be used for direct measurement of total surface contamination within embedded piping include, but are not limited to:
- 1) cylindrical gas-flow prooortional detectors ranging in diameters from 0.5" to 2
2 1.5"; 2) 125 cm gas flow proportiona! detectors; 3) 15.5 cm Geiger-Mueller detectors; and 4) other detector types and sizes as situations dictate. The detectors may be fitted with a delivery device to provide a consistent and reproducible calibration / measurement geometry and to protec* "
etor from damage or po ential contamination.
For embedded piping, total rad removable surface contamination will be measured. The method used to assess removable contamination within embedded piping will consist of one of the following: the measurement of total surface contamination, smear media positioned with a remote handling tool, or smears taken at accessible openings.
O A-30
j YNPS FINAL STATUS SURVEY PLAN REVISION 1 4
v To suppon the conclusion that sections of embedded piping meet the enteria of release for unrestricted use, total surface contamination measurements and removable contamination measurements will typically be performed prior to, during, and after decontamination processes to evaluate the effectiveness of the decontamination technique (s). The decontamination processes will be controlled to ensure that all portions receive similar treatment by the decontamination process, Based upon the effectiveness of the decontamination process, as defined by the measurement results obtained, the radiological condition of any i
inaccessible portion of the embedded piping may be inferred.
j i
EQns! Sediment j
Areas of pond sediment that are included in the final status survey will be surveyed at a frequency of 30 samples per survey unit. Samples will consist of bottom and/or shoreline grab samples.
In Situ Gamma Snectroscony Measurements l
In certain areas of the site,large variations in background exposure rates may result in investigative surveys. Investigative surveys may be performed with in situ gimma spectroscopy to not only identify the radionuclides and their N
concentrations, but also to quantify the exposure rate.
The Environmental Measurement Laboratory (EML) at the US Department of Energy has performed many detailed evaluations of portable gamma spectrometry
+
systems. These evaluations have been instumental to the routine use of gamma spectrometry in radiological environmental monitoring programs to evaluate soll activity concentrations and exposure rates. In situ gamma spectrometry systems have also been used to evaluate radioactive waste containers. In addition, Fort St.
Vrain was approved to use in situ gamma spectrometry to measure exposure rates during their final status survey. Therefore, the technology to convert gamma ray spectra from building surfaces and soil into activity concentrations and exposure rates may be used at YNPS during the course of the final status survey.
4.4.6 Sampling for Hard to Detect Nuclides (HTDN)
Samples will be taken and analyzed from random survey locations in affected areas of the facility. The ratios of HTDN, such as H-3, Fe-55 and Ni-63, to readily detectr.d radionuclides, previcesly used to establish site specific GLVs, will be revised as appropriate.
Both H-3 and Ni-63 cmit low energy beta par'icles during radioactive decay, p-Iron-55 emits low energy X rays during radioactive decay. These decay products V
are difficult to detect with standard field instrumentation. The risk from these A 31
YNPS l'INAL STATUS SURVEY PLAN REVISION 1 O
radionuclides is much lower than the risk from the easily detected Co-60 as shown in the surface concentratio: values of Table B-2 of NUREG-1500 which are between 500 to 5000 times the limit for Co-60. Although dif0 cult to detect, the guideline value equation (Equation 3.1) incorporates the presence of these radionuclides at YNPS.
4.5 Background Level Determinations Background levels will be established for each type of instrument to be used for total surface contamination measurements, removable contamination measurements, and gamma exposure rate measurements. In addition, backgrounds will be determined for specialized detectors and detector systems. These will include large area detectors for floor monitoring and detectors for surveying piping interiors (e.g., multiple GM detectors). For soil and sediment samples, background levels will be determined for those man made radionuclides not resulting from plant activities.
The objectives of background determinations for YNPS final status survey measurements will be to:
Establish the reference background values for each type of 6tector used in the survey.
Assess the variability in background responses for principal detectors under different applications and conditions of use.
Determine the need for correction factors or special measurements to establish the background for final status survey measurements in specific locations.
Account for man made radioactivity not resulting from plant operations.
Background determinations will be performed in accordance with approved procedures.
Values will be re-evaluated as necessary. The methods for background determinations for each type of final status survey measurement are summarized below.
4.5.1 Total S'irface Beta Gamma Measurements Background measurements will be performed on surfaces unaffected by licensed activities. The principal criteria for selection of measurement locations for building surfaces will be the location's similarity to YNPS facility construction and freedom from radioactivity attributable to YNPS operations.
O A-32
YNPS FINAL STATUS SURVEY PLAN REVISION 1 b}
/
4.5.2 Removable Surface Beta Gamma Measurements Background determinations of beta gamma smear counters will be made by taking a count of a blank smear or carrier, usually on each day of operation.
4.5.3 Soll and Sediment Radionuclide Measurements Soil and sediment samples will be collected from areas unaffected by licensed operations in order to establish the background levels of man-made radionuclides not resulting from plant operations. The background samples will be collected at locations similar to their respective on-site sampling locations.
4.5.4 Gamma Esposure Rate Measurements A pressurized ion chamber will be used to establish the background gamma exposure rate at the site, which will be used as the baseline for demonstrating that average residual gamma exposure rate measurements are below 5 pR/hr above background (measured at one meter). The pressurized ion chamber will be used as the reference instrument for establishing the gamma exposure rate background and the pR/hr equivalent response of portable survey meters. T1.e latter will be used for the bulk of the final status survey gamma exposure rate measurements.
This background value will be used for most survey units. Where actual t,ackground conditions are shown to vary significantly, area-specific background values will be used.
Alternatively, in situ gamma spectroscopy may be used to identify those components of the gamma exposure rate that are due to plant contamination, effectively precluding the need for background comparisons. Dominant plant-I related beta gamma emitting radionuclides are discussed in Section 3.3.
I 4.5.5 Specialized Measurements It has been observed that detector background for direct beta gamma measurements is affected by conditions in the immediate vicinity of the detector.
Significant variations from background reference values have been observed.
These variations are caused by the natural radioactivity composition of materials and by shielding effects in some cases. As a result, background measurements for 2
special conditions will be compiled for use in calculating net dpm/100 cm values to reduce the bias in survey unit population statistics. Special condition backgrounds may be compiled for ceramic and clay tile materials, porcelain q
fixtures, poured concrete materials, roofing materials, large bore piping, Q
embedded piping and other materials.
A 33
YNPS FINAL STATUS SURVEY PLAN REVISION 1 0
4.5.6 Verification of Background Measurement Population Each population of background measurements will be analyzed by using the foilowing equation, taken from Equation 8-22 of Draft NUREG/CR-5849, to ensure that the number of measurements in the data set is adequate to characterize the background mean value to within 20% at the 95% confidence level:
t,3,,, Sx (4,1) n, =
0.2 X,
number of background measurements required, n,
=
X mean of background measurements, s
=
standard deviation of initial background measurements, and S
=
x t,55.or =
t statistic for 95% confidence at n 1 degrees of freedom, where n is the number of initial background data points.
4.6 Instrumentatlan Radiation detection and measurement instrumentation for the final status survey will be selected to provide both reliable operation and adequate sensitivity to demonstrate attainment of the release criteria. Detector selection will be based upon detection sensitivity, operating characteristics and expected performance in the field under expected conditions of use.
The principal instruments being evaluated for final status survey measurements are identified in Table 4.1. The detectors used for total surface contamination monitoring will typically be operated with data logging survey meters.
4.6.1 Minimum Detectable Concentration Calculation Minimum Detectable Concentration (MDC) values for field and laboratory counting instrumentation will be determined using the following equation, taken from Equation 3-10 in Draft NUREG-1507 (Reference 10):
1 3 + 3.29 R t,(1+ ')
3 1
(4.2) 3 MDC=
~
E (A/100) t, A-34
YNPS FINAL STA'ITS SURVEY PLAN REVISION 1 (3
V
- where, MDC =
the minimum activity concentration on a surface or material volume that can be statistically detected above background with a 95% probability, sample counting time intervr.),
t,
=
background counting rate, R.
=
background counting time inten al, t,
=
counting efficiency, and E
=
area of the detector, or the area sampled for smear samples.
A
=
4.6.2 Detector Sensitivity The detection sensitivity of some of the detectors being selected for surface contamination measurements has been estimated. These results are summarized o
in Table 4.2. The results are shown for the principal instruments thet are C) expected to be used for field and laboratory beta gamma total surface and removable contamination measurements.
The MDC is dependent on several factors, such as sample count time, background count time, background count rate and detector efficiency. The MDC fcr scan survey measurements will be calculated using Equation 4.2, with the scanning efficiency substituted for the efficiency term.
Count times will be selected to ensure that the measurements will be sufficiently sensitive with respect to applicable GLVs. The count times associated with measurements for total surface contamination and gamma spectral analysis (soil and water) will normally be set to ensum an MDC of <25% of the applicable guideline value.
It should be noted that it may not be possible to scan or take exposure rate measurements at 25% of the applicable GLV, based on significant background interference and the relative instrument sensitivities, as shown in Table 4.2.
p A-35
.W
YNPS FINAI, STATUS StJRVEY PLAN REVISION 1 0
4.6.3 Calibration and Maintenance Instruments and detectors used in the final status survey will be calibrated and maintained at YNPS according to approved procedures. Detectors for beta or gamma measurements will be calibrated using NIST traceable sources. The pressurized ion chamber will be calibrated by the Duke Engineering & Services l
Environmental Laboratory or an appmved vendor, and will also be NIST I
traceable.
4.7 Survey Areas, Units, Locations and Points 4.7.I Survey Areas and Survey Units A survey area is usually a contiguous area with similar characteristics and contamination potential. A survey area will not include both affected and unaffected areas. For plant systems, a survey area may be defined to include an entire system. Individual survey areas will typically not include more than one system.
Engineering judgement will be used to divide a survey area into survey units to support reproducible confirmatory measurements. This will be accomplished by selecting existing facility characteristics such as horizontal and vertical stmetural support beams, concrete pour seams or piping runs to define the boundaries of survey units within survey areas. Distance measurements will be included as necessury to support reproducibility.
In addition, the use of photographs, drawings or maps may be included to support survey unb. identification. This method for area designation will also serve to help survey personnel to define areas of elevated activity requiring addition investigational surveys and/or remediation.
4.7.2 Survey Locations and Survey Points Survey locations will be clearly identified to allow for reproducibility of measurements. Whenever it is appropriate and cost effective, gridding will be used, llowever, the use of appropriate surface markings may be substituted for a physical grid layout.
Survey points will be identified by a unique reference location ID code or nutuber. The numbering convention will allow the survey data to be easily referer,ced to survey points identified on maps or drawings.
O A 36
. YNPS FINAL STA*1US SURVEY PLAN REVISION 1 O
TABLE 4.1 Final Status Survev Instrument Summary Typical hicasurement Type Detector Manufacturer Detector Type Area Density
& Model #
Units 2
Surface Gas Proportional 100 cm Eberline cpm 2
Alpha / Beta-Gamma 1 mg/cm HP-100 CGS 2
Surface Gas Flow 425 cm Ludlum cpm 2
Beta Gamma Proportional 0.8 mg/cm 43-3/
2 Surface Geiger-Mueller 15.5 cm LND/TGM cpm 2
Beta-Gamma 2 mg/cm Gamma Scan Nal (Tl) 2" x 2" Eberline SPA 3 cpm 2
Removable Surface Gas Flow 24.2 cm Protean cpm 2
Alpha / Beta-Gamma Proportional 80 pg/cm WPC 9550 l
Gamma Exposure Pressurized Ion 8 L Sphere Reuter-Stokes pR/hr Rate Chamber (PIC)
RSS-112 Gamma Exposure Compensated I" x 6" Eberline pR/hr Rate Geiger-Mueller HP-270 Gamma Exposure Compensated 2" x 13" Eberline pR/hr Rate Geiger-Mueller HP-300 Gamma High-Purity 2" x 2" EG&G Geometry Spectroscopy Germanium Ortec/ Canberra Dependent Background and High-Purity 2" x 2" EG&G Geometry Special Germanium Ortec/ Canberra Dependent Measurements O
A-37
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
TABLE 4.2 Nominal Measurement Detection Sensitivities IE' I
"'I Detector
Background
(c/d)
Sensitivity Measurement f
Beta-Gamma Pancake GM 150 cpm 0.08 3650 Surface Scan (llP 210/HP-260) dpm/100 cm' 2
Beta Gamma 100cm Gas 550 cpm 0.10 850 2
Surface Scan Proportional dpm/100 cm (lip-100 CGS Beta Gamma 425 cm' Gas Flow 2000 cpm 0 07 500 Surface Scan (Ludlum 43-37) dpm/100 cm' Beta-G.imma Pancake GM 50 cpm 0.10 1800 2
Direct (IIP-210/ lip-260) dpm/100 cm 2
Beta Gamma 100 cm Gas 300 cpm 0.14 450 2
Direct Proportional dpm/100 cm (llP-100 CGS) 2 Alpha Direct 100 cm Gas I cpm 0.25 20 2
Proportional dpm/100 cm (lip-100 CGS)
Gamma Scan Nal (TI) 12,000 cpm 0.012 32,000 2
(SPA 3) dpm/100 cm Gamma Pressurized Ion N/A N/A 1 - 2 pR/h Exposure Rate Chamber (Reuter-Stokes)
Gamma Compensated GM 15 pR/h 1.46 5 pR/h Exposure Rate (HP-270)
Gamma Compensated GM 12 pR/h 1.22 3 pR/h Exposure Rate (HP-300)
Beta-Gamma Gas Flow Proportional I cpm 0.22 70 2
Removable (Protean) dpm/100 cm Alpha Removable Gas Flow Proportional 0.1 cpm 0.26 40 2
(Protean) dpm/100 cm 0
A-38
m.......
i f
YNPS FINAL STATUS SURVEY PLAN -
REYlSION 1 i
i i
DeAne N boundades of tie swwey woe.
~
Peden evalungen haludsg mviewof aperseen and '
_.; histey i
Petemet er evempe meamwed Mmeme NO andly >26% of GLV, er > MDC,whichever i
is leger.
/
YES 1r ClassWy survey ese se Afected.
i t
iP RV -.GuldsIne Wlue ROC. Minimum Detectoide conoontreon YES Close#y es ANected Open Land l
Aras?
NO i,
Fw swt ons show
!meews: Avente.
YEg ef tw meeswoment espected to to *25% of te OW. er klCC iMover le IF9 IW NO ir 3,
C4sesNy suffeces above 2 Classuy elsweenes se metere es Non4uspect AHected.
i sapactAnected casesuy swieces
- 2 nwice m Suspect Aheted.
FIGURE 4.1 Survev-Area Claulfication Process
\\
- A-39 ~
YNPS l'INAL STATUS SURVEY PLAN REVISION 1 0
5.0 DATA PROCESSING ANDINTERPRETATION 5.1 Conversion of Measurements to Reporting Units With respect to the Final Status Survey, removable and total surface cont.,mination will be reported in units of dpm/100 cm', exposure rate will be reported in units of pR/hr, and volumetric material will be reported in units of pCi/g (solids) or pCill (liquids). Prior to comparison with any action level or release criteria, all radioactivity or exposure rate measurements will have the appropriate background subtracted. Corrections for detector size (total surface activity measurements) and instrument response (exposure rate measurements) may also be made, as discussed below.
5.1.1 Total Surface Contamination 2
Total surface contamination measurements will r.ormally be taken with 100 cm detectors (if the detector is smaller, the data will be area corrected to reflect a 2
100 square centimeter area) and compared to the 100 cm average and maximum surface contamination limits.
If large area detectors are used, the observed contamination will be limited to that contamination which would be acceptable when confined to an area of 100 cm'.
Since it cannot be discerned that the observed contamination is uniformly 2
distributed,it will be assumed that it could be attributed to an area of 100 cm or less. In the event that contamination in excess of what would be accep'able for an area of 100 cm' is observed when using a large area detector, an investigation survey will be performed to ascertain compliance with the average guideline values.
Total surface contamination measurement results will be reviewed to ensure that the applied background values are appropriate, If any background values are determined to be inappropriate they will be adjusted as necessary. All adjustments, and theit justifications, will be documented to ensure traceability.
5.L2 Removable Surface Contamination Measurements of removable surface contamination are converted from a gross count raic to units of net dpm/100 cm' by sutitracting the background count rate of the smear counter and dividing the net count rate by the detector efficiency and correcting for the smear area (when necessary). Removable contamination results are then compared to the applicable guideline values.
O A-40
YNPS FINAL STATUS SURVEY PLAN REVISION 1 5.1.3 Exposure Rate Exposure rates will normally be measured with a compensated GM tube with a data logging survey meter. Results from these meters will be compared to the response of a Reuter Stokes pressurized ion chamber (PIC). A correction coefficient will be calculated and applied to each exposure rate measurement to correct the reading to the PIC value. (The PIC is an industry recognized, standard quality device which measures exposure rate at environmental levels with negligible energy dependence.) Measurements may be taken direcdy with the PIC. The appropriate background exposure rate will be subtracted from all measurements.
Alternatively, exposure rates may be determined through in situ gamma spectroscopy. This process identifies those components of the gamma exposure that are due to plant contamination, eliminating the need to subtract background.
Dominant plant-related beta gamma emitting radionuclides are discussed in i
Section 3.3.
I 5.1.4 Soil and other Bulk Samples Soil and other bulk samples are analyzed on a gamma spectrometry system. This g'g system identifies both plant related and naturally occurring radionuclides along with their concentrations and MDCs. Background levels for man made radionuclido are subtracted, as appropriate.
For each sample, those radionuclides that are identified as plant produced are reported and the sum of the ratios (SOR) of their activity to their respective guideline values (GLVs) are compared to unity.
5.2 Comparison with Administrative Action Levels Two categories of administrative action levels have been established. The first is to i
initiate reclassification (see Section 4.1.6) and the re-surveying of an area when survey results indicate that more extensive surveying is needed. The second is to either directly initiate remediation, or where more data are needed to ascertain whether or not the survey unit meets the release criteria, to initiate an investigation. Each of these is specific to the type of survey (removable contamination, total surface contamination, soil and bulk material, or exposure rate) and to the classification of the area being surveyed (affected, suspect affected, non-suspect affected or unaffected). These action levels are shown in Table 5.1. Specific requirements for the handling of data revolving around investigation surveys are described in Section 5.2.4.
Most action levels are based on a direct comparison of a sir.gle measurement or the mean of a group of measurements with the applicable guideline value. Two other comparisons A-41
YNPS FINAL STATUS SURVEY l'LAN REVISION 1 O
are also described in this section. The first involves the calculation of a weighted mean for an elevated activity area, and the comparison of that weighted mean with the guideline value. The second comparison is done to ensure that the mean a tivity level in a survey ui,it meets the release criteria at the 95% confidence level.
5.2.1 Mean and Standard Deviation In order to compare survey measurement results to administrative action levels, a mean and standard deviation must be calculated for each type of measurement for each survey unit.
Mean The mean is calculated as follows:
1 x=-[x (5.1) i n i.i
- where, 1 = sample mean, O
x4 = individual measurement values, n = total number of measurements in the survey unit.
Standard Deviation The standard deviation is calculated as follows:
8 (5.2) s* = h n-I
- where, s, = sample standard deviation, x = individual measurement values, i
1 = sample mean, O
n = number of measurements in the survey unit.
A-42
YNPS MNAL $TATUS SURVEY PLAN REVISION 1 5.2.2 Elevated Areas of Contamination Levels of residual contamination that exceed a guideline value will be evaluated against an elevated area criterion, as defined in NUREG/CR-5849. A weighted mean is calculated for a defined area, and that average is compared against the guideline value. The weighted mean for total surface contamination measurements is based on the average surface contamination within a contiguous I m' area. For soll, the average is based on an area of 100 m'. The equations and their use are described below.
For exposure rates, the mean (equation 5.1) is used instead of the weighted mean.
Exposure rates on structures can be averaged over 10 m' and outdoor areas can be 2
averaged over 100 m.
Surface Contamination When total surface contamination is between one and three times the guideline.
value, additional measurements will be performed to further characterize the level 4
and areal extent of the contamination. The weighted mean is then calculated to 2
determine whether the average contamination level within a contiguous 1 m area containing the elev.eted area is less than the guideline value. Where the weighted mean exceeds the guideline value, or where an individual measurer sent exceeds three times the guideline value, the area will be remediated. Equation 5.3 is used
'or the calculation of the weighted mean.
Soll and Sediment When a radionuclide concentration is between one and three times the guideline value, additional measurements will be performed to detennine the activity level and its areal extent. If the concentration in the elevated area exceeds the guideline value by a factor of (100/A)u2, where A is the area of the elevated 2
activity in m, the area must be remediated. If the concentration in the elevated 4
area does not exceed the guideline value by a factor of(100/A)"2 the weighted mean activity in the 100 m' contiguous area is then determined and compared agcinst the guideline value. If the weighted mean exceeds the guideline value, or an individual measurement exceeds three times the guideline value, the elevated area will be remediated. Equation 5.3 is used for the calculation of the weighted mean.
The weighted mean is calculated as follows:
p'
( = 1 [a,L x, 1 -[ A
+[ yA, M.M n.
ni g
g g-n, i.: -
t.:
t.:
A-43 g
.,r....
m -
n.
,m
YNPS FINAL STATUS SURVEY PLAN RTVISION 1 O
- where, i,
weighted mean including elevated area (s),
=
number of systematic and random measurements, n,
=
systematic and random measurements at point i, x,
=
number of elevated areas, n,
=
2 fraction of I m'(100 m for soil) occupied by elevated area k, and A
a g
elevated area activity in area k.
y,
=
b' ate:
For plant systems and embedded piping surface contamination measurements, equation 5.3 will not be used. In these cases, equation 5.1 (a non-weighted mean) will be used to determine average contamination levels.
5.2.3 Calculation of the 95% (..fidence Interval of the Mean After the mean levels are shown to satisfy the guideline values and conditions, the results will be further evaluated to determine whether the data for each survey unit provides a 95% confidence level that the true mean activity level meets the guidelines. The confidence interval is calculated using normal statistics (one-tailed test) at the 95% confidence level, as follows:
s" P. = x + t,.,, O-. -
(5.4)
- where, upper confidence limit of sample mean, p,
=
i sample mean,
=
student t statistic for the degree of confidence and degrees of t,
=
i freedom; df(degrees of freedom) is equal to n - 1, and a is 0.05 for this test, sample standard deviation, which includes the weighted means for s,
=
any elevated areas, and number of measurements in the survey unit.
n
=
A-44
YNPS FINAL STATUS SURVEY PLAN REVISION 1 The valu p, will be compared with the guideline value. If p, is less than the guideline, the area being tested meets the guideline at a 95% confidence level.
This means that the probability is less than 5% that p, will pass the test when the true mean activity level exceeds the guideline value.
Where p,is greater than the guideline value and the mean is less than the guideline value (i.e., the test of confidence is inconclusive), either (1) remediation will be conducted, followed by a re survey, or (2) additional measurements / sampling will be performed.
5.2.4 Processing of Investigation Survey Data If during an investigation survey the initial measurement results cannot be confirmed, the initial measurement results will be replaced by the invest gative i
data. The investigation measurement results will be considered as the final status survey of record and will be included in the calculation of the mean and standard deviatior, for the survey unit to determine compliance with the guideline values.
If during an investigation survey the initial measurement results are confirmed, and remediation and/or reclassification is required, the initial measurement results n
will be archived as characterization data in the final status survey database. The V
results of the post remediation final status survey, or the final status survey subsequent to reclassification, will be considereo as the final status survey of record and will be included in the calculation of the mean and standard deviation for the survey unit to determine compliance with the guideline values.
If during an investigation survey the initial measurement results are confirmed, but remediation and/or reclassification is not required, the initial measurement results and the investigation survey results will be evaluated by the weighted mean equation. The weighted mean value will replace the initial value and be considered as the final status survey result for the location of record. The new value wi:1 then be included in the calculation of the mean and standard deviation for the survey unit to determine compliance with the guideline vclues.
5.3 ALARA Analysis In the YNPS Final Safety Analysis Report, Yankee committed to a site release criterion of 15 mrem / year Total Effective Dose Equivalent (TEDE). Yankee also committed to an optimization process based on ALARA principles to reduce the residual levels of radioactivity on the site commensurate with the minimization of total risk. The ALARA analysis will take into account the following:
V A-45
YNPS FINAL STATUS SURVEY PLAN REVISION 1 Ol Radiation doses and environmental impacts from the decommissioning proc ess and from the residual radiation remaining on the site after completion of decommissioning.
Other costs and risks associated with the decontamination and decommissioning of the site.
See Section 4.4 of the License Termination Plan for more details.
O O
A-46
C v
YNPS FINALSTATUS SURVEY PLAN REVISION 1 -
TABLE 5.1 Summary of Action Levels for Reclassification and Remediation*
SURVEY TYPE REMOVABLE TOTAL SURFACE SOIL and BUT -' MATERIAL
'X)?fTAMINATION CONTAMINATION CONr'-
TION EXPOSURE RATE a
R:classifict-n Reclassify if mean > 25% of GLV.
a) Reclassify if single.nea. 'nent Action Level **
NA SOR > 0.75.
NA I
b) Reclassify if mon of SORS I
> 0.25.
I Remediation a) Remediate if single a) Remediate if single measurement a) Remediate if single measurement a) Remediste if single Action levels *"
meastaement > GLV;
> 3 x GLV; SOR > 3; measurement I
> 10 pR/hr:
b) Remediate or take more b) Rerrediate if mean > GLV; b) RcWiate if mean of SORS > I; I
samples if mean < GLV and b) Remediate if mean p > GLV.
c) Remediate if single measurement c) Remediate if single measurement
> 5 pR/hr; i
> GLV and weighted mean over SOR > 1 and the mean of SORS i
1 m'is > GLV;
> (100/A)";
c) Remediate or take I
more samp!cs if mean d) Remediate or take more samples d) Remediate or take more samples
< 5 pR/hr and p > 5 if mean < GLV and p. > GLV.
if mean of SORS < 1 and p, > 1.
pF/hr.
I The table is a summary. Refer to Section 5.2 for complete information on the above action levels. All measurements assume the appropriate background has been subtracted.
Reclassification applies only to unaffected or non-suspect affected areas. Unaffected Areas will be reclassified as Affected. Non-Suspect Affected Areas will be reclassified as Suspect Affected.
Reclassification will be required following remediation for Unaffected and Non-Suspect Affected Areas. As described in the text, some of the remediation action levels in this tabic allow for the collection of additional samples as a possible alternative to remediation.
A-47 r
e
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
Perform uenwwnents and S* @
+
Conve1 Data to standa1 Units
+
Cat.vwe savn Una usan and staward Devuton
+
Compers wth Reclassl6caton Reclar:Py Crtofta u
Exceeds Reclasstraton CrRefis?
NO or N/A Ratnadels or Take More O"P*#
Remodebon g
Acbon Levels Exceeds YES g,gg Acton Levels NO Calculat fur 95%
Confklence Lwei Colect
+
AdstenalData Compare Wth GLV YES*
Exceeds YES' GLV7 GLV Gu&line Value MDC WinimumDetscable Concentration NO e
Inp&es Cteke of Actions Prepare FtwlReport FIGURE 5.1 Interoreting and Comparing Survey Data with Guideline Values O
A-48
=
YNPS FINAL STATUS SURVEY PLAN REVISION 1
(~(>)
6.0 FINAL STATUS SURVEY REPORTS Upon completion of each major final status survey phase an interim report will be prepared for review by the Nuclear Regulatory Commission. Upon completion of all final status survey phases, a final report will be prepared. These reports will meet the intent of draft NUREG/CR-5849 and Regulatory Guide 1.86 for final status survey reporting.
' 6.1 Topical Outline The following outline illustrates a general format for the final report for the final status survey. The outline below may be adjusted to provide a clearer presentation of the information. The level of detail will be sufficient to clearly describe the final status survey program and certify the results.
1.0 Background Information 2.0 Site Description 3.0 Operating History 4.0 Decommissioning Activities 5.0 Final Status Survey Methodology 6.0 Final Status Sun'ey Results 7.0 Summary 6.2 Reporting of Survey Findings 6.2.1 Detail Data Reporting for Each Survey Area A computer generated report for each survey area will be generated which will show all measurement results, both positive and negative. In addition, the reports will show the conversion factors, backgrounds and the MDCs to allow independent verification of the results. These measurement results may also be presented graphically. If requested by the NRC, these data may be provided in electronic form.
6.2.2 Summary Data Reporting for Each Survey Area A computer generated summary of the measurement results for each survey area will be provided. The number of measurements, the average and maximum values, and the upper limit of the confidence interval about the mean for each survey unit in a survey area will be reported for comparison to the release criteria.
If requested by the NRC, these data may be provided in electronic form.
h A-49
YNI'S FINAL STATUS SURVEY l'LAN REVISION 1 O
6.3 Final TEDE Evaluation Following completion of the final status survey, the survey data will be used to produce an annual TEDE to an average member of the critical population group. An assessment tool, such as the computer code RESRAD or D&D Screen, will be utilized in accordance I
with applicable NRC guidance to perform this dose analysis. All realistic pathw., L I
exposure, including direct exposure, drinking water, and agriculture, will be mcluded.
The objective of this analysis will be to demonstrate that the annual dose to any real individual will be well below the 15 mrem. In accordance with 10 CFR 20.1401(d), the I
dose calculated shall be the peak annual TEDE expected within the first 1000 years after I
decommissioning.
I 9
O A-50
YNPS FINAL STATUS SURVEY PLAN REVISION 1
7.0 REFERENCES
7.1 Survey Plan References 1.
U.S. Atomic Ersers,y Commission, Regulatory Guide 1.86, " Termination of Operating Licenses for Nuclear Reactors," dated June 1974.
2.
Draft NUREG/CR 5849, Manual for Conducting Radiological Surveys in Support of License Termination, June 1992 (Draft).
t 3.
Draft NUREG-1500, Working Draft Regulatory Guide on Release Criteria for Decommissioning: NRC Staffs Draft for Comment 4.
YNPS Decommissioning Plan, Revision 0.0 5.
SECY-94-145, " Increase of Tritium and Iron 55 Unrestricted Use Limits for Surface Contamination at Shoreham and Fort St. Vrain," dated May 27,1994.
6.
YAEC letter, J.K. Thayer to M.B. Fairtile, dated August 5,1994, " Request for Additional Information on Yankee Nuclear Power Station's Decommissioning Plan and Decommissioning Environmental R ; port."
7.
NRC Letter, C.L. Pittiglio to A.C. Crawford (Public Service of Colorado),
" Response to Proposed Modification of Removable Surface Contamination Release Criteria of Removable Surface Contamination for Tritium and Iron-55 at Fort St. Vrain Nuclear Generating Station," dated January 18,1995.
8.
Yu, C.F. et al., Manual for Implementing Residual Radioactivity Materials Guidelines Using RESRAD, Environmental Assessment Division, Argonne National Laboratory.
9.
Draft NUREG 1505, A Nonparametric Statistical Methodology for the Design and Analysis of Final Status Decommissioning Sun'eys, dated August 1995.
10.
Draft NUREG-1507, Minimum Detectable Concentrations with Typical Radiation Survey Instruments for Various Contaminants and Field Conditions, dated August l
1995.
I 1. -
D&D Screen Interim Release 1.0, Sandia National Laboratories.
I I
- 12.
Draft NUREG 5512, Residual Radioactive Contamination from i
Decommissioning, dated October 1992.
I A 51
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
7.2 Procedure References 1.
AP-8800,
" Final Status Survey Organization Training and Technical Basis Documents" 2.
AP-8801, "FSS Survey Area Classification and Description" 3.
DP-8802, "FSS Survey Location Designation" 4.
OP-8803, "FSS Package Preparation, Issuance and Closure" 5.
OP-8804, "FSS for Systems and Structures" 6.
OP-8805, "FSS for Open land Areas" 7.
OP-8807 "FSS Background Assessment" 8.
OP-8808, "FSS Data Receipt and Manasement" 9.
OP-8809, "FSS Data Processing" 10.
AP-8810, "FSS Survey Area Turno er and Control" 11.
AP-8812,
- FSS Quality Control" O
A-52
YNPS ITNAL STATUS SU2VEY PLAN REVISION 1 g
8.0 GLOSSARY 2
Accessible Surface Area - An area accessible to a 100 cm proportional detector or a 2
15.5 cm GM detector for direct or scanning measurements.
Administrative Action Level-A contamination level used as the investigation threshc14 in survey units to evaluate the need for additional investigation, reclassification or remediation.
Backeround Radiation - Naturally occurring radiation which may include cosmic, terrestrial (radiation from the naturally radioactc - lements) and man-made radiation from global fallout.
Characteri7ation Survey - A radiological survey and its supporting evaluations performed to establish the YNPS radiological condition for planning deconimissioning activities.
Confidence Interval-A range of values derived from a sample sur h that there is a probability that a population parameter being estimated, e.g., a mean value, lies within the range.
Confidence Level - The probability associated with a confidence interval which (qj expresses the probability that the confidence interval contains the population parameter value bem, g estimated.
Elevated Area - Areas of residual contamination exceeding the guideline value.
Final Status survey - Radiological measurements, evaluations and supporting activities undertaken to demonstrate that the YNPS facility satisfies the criteria for unrestricted use.
Guideline Wlue - (GLV), residual radioactivity levels that equate to the site release criteria for that particular pathway or measurement.
Hard-to-Detect Nuclide -(HTDN), A radionuclide emitting adiation(s) that are difficult to detect with field instrumentation.
Historv File - A compilation of information prepared for use in planning the final status survey of a survey area. It summarizes the operational history, characterization survey data, operational surveys and other information to help establish the basis for the design of the final status survey.
Minimum Detectable concentration - The minimum activity concentration on a surfa:e
,- m or material volume that can be statistically detected above background. This is usually set (v) at the 95% confidence level.
A-53
YNPS FINAL STATUS SURVEY PLAN REVISION 1 O
Operational _R dio!ogical Survey-A radiological survey performed in accordance with YNPS procedures. Operational surveys are distinct from, and usually performed prior to, s
final status surveys.
Release criteria - A term used to identify the radiological requirements for release of the
/
YNPS facility for unrestricted use.
Replicate Survey - A survey which consists of repeat measurements on a specified fraction of survey areas. The survey areas are usually selected at random to provide an independent check of final status survey measurements.
Sun Survey - A qualitative radiological monitoring technic,ue which is performed by moving a detector over a surface at a specified constan' speed to detect elevated activity levels. Also called Surface Scan.
S!nicluttu - All YNPS site buildings and their surfaces. In addition, platforms, restraints and supports, and external surfaces of piping systems, heating and ventilatic>n systems, tanks, stacks, etc., are also treated as stmetures in the final status survey.
Sum of Ratlos - Where more than one radionuclide is present, the sum of the ratios of each radionuclide concentration to its respective GLV should not exceed unity.
Surface Contamination - The total of both fixed and removable contamination. For the purposes of this Plan, this would also include any remaining neutron-activated material.
Also called total surface contamination.
Survey Area - The basic entity for the management of the Final Status Survey. It is comprised of one or mor. survey units, the bounds of which are defined by existing facility physical features, such as a room, intersection of walls, column-and-row layout of a flooi elevation, or structural I beams.
Smyev Location - In a structural or open land survey area, a survey location is usually represrted by a single grid block. In a system survey area, a specified length of piping or a component such as a valve er tank is referred to as a survey location. A survey location can contain one or more survey points. Also referred to as a Measurement Location.
Survey Package - A collection of information in a staadardized format for controlling and documenting field measurements taken for the Final Status Survey. A survey package is prepared for each survey area. The survey package may include the survey instructions, a control form, grid map (s), survey measurement data sheets and survey maps.
O 4
A-54
I YNPS FINAL STATUS SURVEY PLAN REVISION 1
)
s Survey Point - A smaller subdivision within a survey location'(grid block, system, component) where local measurements are taken. For structures and systems, a survey point generally refers to an area covered by a detector, or an area of 100 cm' when a smear is taken. For open land areas, a survey point refers to the area covered by a detector (for paved surfaces), the point at which an exposure rate measurement is taken, or the point at which a soil or pavement sample is collected.
Survev Unit - A contiguous area (usually) with similar characteristit.s and contamination potential. Survey units are established to facilitate the survey process and aid in the statistical evaluation of the survey data. Because survey units are generally designed to be contiguous areas with similar characteristics and potential for contamination, the actual size of r, survey unit is not deemed to be critical, provided each survey unit contains a sufficient nurber of measurement locations.
10.ta) Effective Dose Equivalent (TEDF1 - The surn of the deep dose equivalent (for external exposures) and the committed effective dose equivalent (for internal exposures).
,x A-55
-