ML052140253

Final Status Survey Report for Saxton Nuclear Experimental Corporation Residual Macadam in OL1.

ML052140253
Person / Time
Site:	Saxton File:GPU Nuclear icon.png
Issue date:	07/31/2005
From:	GPU Nuclear Corp
To:	Office of Nuclear Reactor Regulation
References
Download: ML052140253 (29)

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Final Status Survey Report For Saxton Nuclear Experimental Corporation Residual Macadam in OL1 Prepared by GPU Nuclear, Inc.

July 2005

Table Of Contents Executive Summary

1.0 Purpose and Scope

2.0 Survey Area Description 3.0 Operating History 3.1 Plant Operations 3.2 Survey Area Remediation Status 4.0 Site Release Criteria 5.0 Final Status Survey Design / DQO Process 6.0 Final Status Survey Results 6.1 Summary for Survey Unit MA8-6 6.2 Summary for Survey Unit MA8-7 6.3 Summary for Survey Unit MA8-8 6.4 Summary for Survey Unit MA8-9 6.5 Summary for Survey Unit MA8-10 6.6 Summary for Survey Unit MA8-11 6.7 Summary for Survey Unit MA8-12 6.8 Summary for Survey Unit MA8-13 6.9 Summary for Survey Unit MA8-16 6.10 Summary for Survey Unit MA8-17 7.0 Data Assessment 7.1 Assessment Criteria 7.2 Summary of Overall Results 7.3 Survey Variations 7.4 Quality Control Measurements 8.0 Final Survey Conclusions 9.0 References 10.0 Appendices i

Executive Summary This report presents the results and conclusions of the final status survey (FSS) of the Class I macadam surfaces of the Saxton Nuclear Experimental Corporation (SNEC) facility designated as numerous units in the OL1 area. This FSS includes surveys of residual macadam surfaces throughout the OL1 area of the SNEC site. The survey was conducted in June of 2005.

The FSS was performed in accordance with the SNEC License Termination Plan (LTP). The macadam portions of the survey area were divided into ten survey units. Each of these units consisted of relatively flat residual macadam pavement surfaces. Data was collected from each survey unit in accordance with the specific survey design data collection requirements. The following is a summary of the measurements performed:

1) Direct Gas Flow Proportional Counter (GFPC) scans of all of the macadam surfaces in 18 grids covering about 42% of the actual surface area

2) One hundred and eleven fixed point static GFPC measurements.

The collected FSS survey data demonstrate that the approximately 760 square meters of the macadam surfaces in the OL1 survey area meet the radiological release criteria for unrestricted use specified in 10CFR20.1402. Therefore GPU Nuclear, Inc. concludes that the area meets the NRC requirements and may be released for unrestricted use.

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1.0 Purpose and Scope

This report presents the results and conclusions of the final status survey of the residual macadam pavement throughout the OL1 area of SNEC facility. Survey units MA8-6, MA8-7, MA8-8, MA8-9, MA8-10, MA8-11, MA8-12, MA8-13, MA8-16, and MA8-17 are included. This report provides the information required by IOCFR50.82(a)(1 1) and the SNEC license termination plan (LTP) to demonstrate that this area meets the radiological criteria for unrestricted use specified in 10CFR20.1402.

This report describes the radiological data collected in ten Class I survey units of residual macadam. This report only addresses the FSS performed on this specific portion of the area designated as OL1. The format of this report follows the guidance contained in reference 9.2.

2.0 Survey Area Description Survey Area OL1 is primarily the area including and surrounding the original SNEC facility, surrounding the Penelec line building (the 'line shack'), and the northern half of the Saxton Steam Generating Station (SSGS) footprint. The ten macadam survey units are all designated as Class 1. The reference 9.1 map shows the designations of the soil areas of the OL1 survey area. The survey unit encompasses about 760 square meters of macadam surface within 18 grids of the larger OL1 area. Most OL1 grids did not contain any macadam surfaces and some grids contained parts of more than one survey unit due to the layout of the discrete macadam sections. Layout of the survey area and individual units relative to the site layout are shown in Attachment 1 of Appendix A. The ten survey units are discussed below. The survey unit designations are derived from the sequence provided in table 5-2 of the SNEC LTP (reference 9.3).

Survey unit MA8-6 is residual macadam in the Class 1 soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 96 square meters in 3 grids. The initial survey design estimated 76 square meters and 20 square meters of small adjacent macadam areas was added. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-1 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-7 is residual macadam in the Class 1 soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 81 square meters in 2 grids. The initial survey design estimated 76 square meters and 5 square meters of small adjacent macadam areas was added. Appendix A 2 of 27

attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-3 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-8 is residual macadam in the Class 1 soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 100 square meters in 2 grids. The initial survey design estimated 76 square meters.

The area was estimated to be 95 square meters during the survey and 5 square meters of small adjacent macadam areas was added. Appendix A attachments 1-I and 6-17 are drawings showing the layout of the survey area and attachment 6-5 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-9 is residual macadam in the Class 1 soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 52 square meters in 2 grids. The initial survey design estimated 76 square meters but the area was estimated at 48 square meters during the survey and 4 square meters of small adjacent macadam areas was added. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-7 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-10 is residual macadam in the Class I soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 76 square meters in 3 grids. The initial survey design estimated 102 square meters but 26 square meters was not scanned because it was patches of soil within the macadam area. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-9 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-11 is residual macadam in the Class I soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 42 square meters in 1 grid. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-11 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-12 is residual macadam in the Class 1 soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 82 square meters in 4 grids. The initial survey design estimated 73 square meters but additional area was added based on the survey and about 7 square meters was not surveyed because it was patches of soil within the macadam area. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area 3 of 27

and attachment 6-13 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-13 is residual macadam in the Class 1 soil areas south of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 83 square meters in 1 grid. The survey unit was estimated to be 100 square meters during the design, but the survey estimated the area to be about 83 square meters.

Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-15 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-16 is residual macadam in the Class 1 soil areas west of the original SNEC facility area. It has been designated Class 1 conservatively based on the proximity to the SNEC facility. The survey unit is approximately 93 square meters in 3 grids. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-22 of appendix A shows the layout of the macadam in this specific survey unit.

Survey unit MA8-17 is residual macadam in the Class 1 soil areas west of the original SNEC facility area. It has been designated Class I conservatively based on the proximity to the SNEC facility. The survey unit is approximately 58 square meters in 2 grids. Appendix A attachments 1-1 and 6-17 are drawings showing the layout of the survey area and attachment 6-24 of appendix A shows the layout of the macadam in this specific survey unit.

3.0 Operating History 3.1 Plant Operation The Saxton Nuclear Experimental Corporation (SNEC) facility included a pressurized water reactor (PWR), which was licensed to operate at 23.5 megawatts thermal (23.5 MWTh). The reactor, containment vessel and support buildings have all been removed. The facility is owned by the Saxton Nuclear Experimental Corporation and is licensed by GPU Nuclear, Inc. The SNEC facility is maintained under a Title 10 Part 50 license and associated Technical Specifications. In 1972, the license was amended to possess but not operate the SNEC reactor.

The facility was built from 1960 to 1962 and operated from 1962 to 1972 primarily as a research and training reactor. Steam from the SNEC reactor was directed to the adjacent Saxton Steam Generating Station (SSGS) to generate electricity.

After shutdown in 1972, the facility was placed in a condition equivalent to the current SAFSTOR status. Since then, it has been maintained in a monitored condition. The fuel was removed in 1972 and shipped to a (now DOE) facility at 4 of 27

Savannah River, SC, who is now the owner of the fuel. As a result of this, neither SNEC nor GPU Nuclear, Inc. has any further responsibility for the spent fuel from the SNEC facility. The building and structures that supported reactor operation were partially decontaminated by 1974.

In the late 1980s and through the 1990s, additional decontamination and disassembly of the containment vessel and support buildings and final equipment and large component removal was completed. Final decontamination and dismantlement of the reactor support structures and buildings was completed in 1992. Large component structures, pressurizer, steam generator, and reactor vessel were removed in late 1998. Containment vessel removal (to below grade) and backfill was completed in late 2003. Currently, decontamination, disassembly and demolition of the SNEC facility buildings and equipment has been completed and the facility is in the process of Final Status Survey for unrestricted release and license termination.

3.2 Survey Area Remediation Status No known remediation activities have been conducted on the residual macadam surfaces discussed here. Surface cleaning to permit the survey was performed and portions of the macadam were removed in order to remove materials that were underground (pipe tunnels, drain lines etc.).

4.0 Site Release Criteria The site release criteria applied to the macadam surface areas of OL1 correspond to the radiological dose* criteria for unrestricted use per 10CFR20.1402. The dose criteria is met 'if the residual radioactivity that is distinguishable from background radiation results in a Total Effective Dose Equivalent (TEDE) to an average member of the critical group that does not exceed 25 mrem/yr, including that from groundwater sources of drinking water, and that the residual radioactivity has been reduced to levels that are as low as reasonably achievable (ALARA)".

Levels of residual radioactivity that correspond to the allowable dose to meet the site or survey unit release criteria for structural surfaces were derived by analyses using a building re-use scenario. The dose modeling for this scenario is explained in the SNEC LTP (reference 9.3). The derived concentration guideline levels (DCGL) shown in Table 5-1 of the SNEC LTP form the basis for satisfying the site release criteria.

Residual radioactivity sample results from the original SNEC yard area were used to calculate a surrogate Cs137 DCGL. The adjusted surrogate DCGL was developed using the methodology described in the SNEC LTP section 5.2.3.2.3 based on nuclide specific DCGLs from Table 5-1 of the LTP.

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An adjustment was made to the surrogate Cs137 DCGL to address the de-listed radionuclides as described in the LTP section 6.2.2.3. SNEC has instituted an administrative limit of 75% of the DCGL for all measurement results. The de-listed radionuclides are conservatively accounted for in this 25% reduction since the de-listed radionuclides were only 4.7% of the dose contribution. These adjustment factors are discussed in section 6 of the SNEC LTP.

5.0 Final Status Survey Design and DQO The SNEC calculation providing the design of the survey for these survey units is provided in Appendices A and B. Scan measurements were conducted over approximately 100% of the Class 1 survey units. Scans were planned to be conducted using two different types of large Gas Flow Proportional Counter (GFPC). Most FSS surveys have been conducted using a model 43-68 GFPC which is about 126 square centimeters. Because of the large area of fairly flat macadam, an additional detector, a 43-37 'extra large' GFPC was used.

Setpoints for the 43-37 were conservatively determined and then the detector was used only for surface scanning in a screening process. If any alarm points were found with the 43-37, follow-up would be conducted with the more

'traditional' 43-68 detector. Appendix B section 2.1.11 explains the 43-37 detector and conditions of use. Although considered in the design if needed, no 43-68 scans were required for this survey unit group.

The number of fixed measurement points was determined by using the COMPASS computer program (reference 9.5, attachment 7 of appendix A).

These points were located on survey maps using the Visual Sample Plan program (reference 9.6 and attachment 6 of appendices A and B). One survey units had more fixed point measurements than the minimum COMPASS indicated. This was due to layout on the shape of the survey unit.

The survey design uses a surrogate Cs137 effective DCGL developed from radionuclide mix analyses from samples collected before the Final Status Survey in the vicinity of the survey unit. For OL1 the mix was based on radionuclide mix data (including the hard-to-detects listed in Table 5-1 of the LTP) from soil samples from the areas of the original SNEC site in OL1 and OL2 (attachment 2 of appendix A).

Cs137, Co6O, H3, and Sr9O were positively detected in one or more of these samples and are accounted for in the adjusted surrogate DCGL. The following table (Table 1) presents the Data Quality Objectives (DQO) and other relevant information from the survey design package.

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Table 1 - DQO/Design MA8-6, MA8-7, MA8-8, MA8-9, DQO/Design Parameter MA8-10, MA8-11, MA8-12, MA8-13, MA8-16, MA8-17 SNEC Design Calc. # E900-05-015 MARSSIM Classification I 96,81, 100,52, 2

Survey Unit Area (m ) 76, 42,82, 83,93,58 Statistical Test Sign Type 1 decision error (a) 0.05 Type 2 decision error (P) 0.1 LBGR (cpm) 1175 Estimated cr (cpm) 25.4 Relative Shift (A/cr) 3.0

_ 11,11, 11, 11, Number of static points* 11, 12,11, 11,11, 11 DCGLw (Cs137 dpm/lOOcm 2 ) 26445 Action Level (Cs137 19834 dpm/lOOcm2) 1_ 3 Scan MDC (dpm/100cm 2 ) 4634 (43-68)

_7311(43-37)

SNEC Survey Request # SR234, SR235, SR236 Scan Survey Instrument L2350-1 w/ 43-37 minimum per design was I1 in each unit 6.0 Final Status Survey Results The following sections provide the survey summary results for each survey unit as required by the respective design. Summary data was taken from references 9.9, 9.10, and 9.11 which are filed in the SNEC history files.

6.1 Survey Unit MA8-6 6.1.1 Scan survey Scan measurements were made on the residual macadam in part of 3 grids using a 43-37 GFPC detector with an MDCscan of 7311 dpm/1 00cm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/10cm2 7 of 27

(table 1 on page 3 of appendix A), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/100cm 2 (table 1 on page 3 of appendix A). In this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Initial design estimate of surface area was 76 square meters. The final estimate of the area from the survey was 96 square meters including about 20 square meters of adjacent macadam added to this unit to ensure complete coverage of the macadam. All of the 96 square meters of macadam as found during the survey was scanned. This results in approximately 96 square meters actually scanned in the 96 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 96 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found in MA8-6.

6.1.2 Fixed point measurements Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-6 had results in excess of the adjusted surrogate DCGLw. The table below (Table 2) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

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Table 2 - Fixed point results for MA8-6 Point Gross Number beta cpm 1 337 2 411 3 387 4 472 5 396 6 358 7 394 8 332 9 355 10 403 11 390 Mean 385 Std Dev 39.4 Min 332 Max 472 6.2 Survey Unit MA8-7 6.2.1 Scan survey Scan measurements were made on the residual macadam in part of 2 grids using a 43-37 GFPC detector with an MDCscan of 7311 dpm/1OOcm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/100cm 2 (table 1 on page 3 of appendix A), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/1OOcm 2 (table 1 on page 3 of appendix A). In this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Initial design estimate of surface area was 76 square meters. The final estimate of the area from the survey was 81 square meters including about 5 square meters of adjacent macadam added to this survey unit for completeness of coverage. All of the 81 square meters of macadam was scanned. This results in approximately 81 square meters actually scanned in the 81 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 81 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found in MA8-7.

6.2.2 Fixed point measurements 9 of 27

Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-7 had results in excess of the adjusted surrogate DCGLw. The table below (Table 3) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

Table 3 - Fixed point results for MA8-7 Point Gross Number beta cpm 1 364 2 343 3 372 4 362 5 349 6 359 7 364 8 460 9 288 10 512 11 429 Mean 382 Std Dev 61.9 Min 288 Max 512 6.3 Survey Unit MA8-8 6.3.1 Scan survey Scan measurements were made on the residual macadam in part of 2 grids using the 43-37 GFPC detector with an MDCscan of 7311 dpm/1OOcm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table 1 on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/100cm2 (table 1 on page 3 of appendix B). In 10 of 27

this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Initial design estimate of surface area was 76 square meters. The final estimate of the area from the survey was 100 square meters including about 5 square meters of adjacent macadam added to this survey unit for completeness of coverage. All of the 100 square meters of macadam was scanned. This results in approximately 100 square meters actually scanned in the 100 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 100 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found in MA8-8.

6.3.2 Fixed point measurements Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-8 had results in excess of the adjusted surrogate DCGLw. The table below (Table 4) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

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Table 4 - Fixed point results for MA8-8 Point Gross Number beta cpm 1 381 2 357 3 310 4 322 5 386 6 353 7 346 8 432 9 410 10 424 11 424 Mean 377 Std Dev 42.5 Min 310 Max 432 6.4 Survey Unit MA8-9 6.4.1 Scan survey Scan measurements were made on the residual macadam in part of 2 grids using the 43-37 detector with an MDCscan of 7311 dpm/1OOcm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table 1 on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/1OOcm 2 (table 1 on page 3 of appendix B). In this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Design estimate of the area of the survey unit was 76 square meters. The estimate of the area from the survey was 52 square meters. All of the 52 square meters of macadam was scanned. This results in approximately 52 square meters actually scanned in the 52 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 52 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found with the 43-37 in MA8-9.

6.4.2 Fixed point measurements 12 of 27

Eleven randomly selected fixed point measurement locations were defined for the survey unit based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-9 had results in excess of the adjusted surrogate DCGLw. The table below (Table 5) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

Table 5 - Fixed point results for MA8-9 Point Gross Number beta cpm 1 384 2 510 3 1 370 4 1 435 5 1 358 6 430 7 446 8 402 9 423 10 399 11 379 Mean 412 Std Dev 43.1 Min 358 Max 510 6.5 Survey Unit MA8-10 6.5.1 Scan survey Scan measurements were made on the residual macadam in part of 3 grids using the 43-37 detector with an MDCscan of 7311 dpm/1 00cm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/100cm2 (table I on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/1OOcm 2 (table 1 on page 3 of appendix B). In this 13 of 27

case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Design estimate of the area of the survey unit was 102 square meters. The estimate of the area from the survey was 76 square meters. This includes about 4 square meters of adjacent macadam added to this survey unit for completeness in coverage and not including about 22 square meters of surface that was holes in the surface filled with soil. All of the 76 square meters of macadam was scanned. This results in approximately 76 square meters actually scanned in the 76 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 76 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found with the 43-37 in MA8-1 0.

6.5.2 Fixed point measurements Eleven randomly selected fixed point measurement locations were defined for the survey unit based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-10 had results in excess of the adjusted surrogate DCGLw. The table below (Table 6) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

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Table 6 - Fixed point results for MA8-10 Point Gross Number beta cpm 1 430 2 364 3 329 4 317 5 353 6 331 7 426 8 385 9 377 10 373 11 362 Mean 368 Std Dev 36.6 Min 317 Max 430 6.6 Survey Unit MAB-11 6.6.1 Scan survey Scan measurements were made on the residual macadam in part of I grid using the 43-37 detector with an MDCscan of 7311 dpm/1 00cm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table 1 on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/100cm2 (table 1 on page 3 of appendix B). In this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Design estimate of the area of the survey unit was 42 square meters. All of the 42 square meters of macadam was scanned. This results in approximately 42 square meters actually scanned in the 42 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units.

The scans conducted in all 42 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 cpm was found with the 43-37 in MA8-1 1.

6.6.2 Fixed point measurements 15 of 27

Twelve randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. The minimum number required was eleven, but twelve fit on the survey unit when the grid was applied. None of the design fixed point measurements in MA8-11 had results in excess of the adjusted surrogate DCGLw. The table below (Table 7) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

Table 7 - Fixed point results for MA8-11 Point Gross Number beta cpm 1 371 2 346 3 387 4 431 5 353 6 376 7 341 8 311 9 440 10 374 11 350 12 407 Mean 374 Std Dev 37.8 Min 311 Max 440 6.7 Survey Unit MA8-12 6.7.1 Scan survey Scan measurements were made on the residual macadam in part of 4 grids using the 43-37 detector with an MDCscan of 7311 dpm/1 OOcm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table 1 on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this 16 of 27

survey unit was 26445 dpm/1OOcm 2 (table 1 on page 3 of appendix B). In this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Design estimate of the area of the survey unit was 73 square meters. The estimate of the area from the survey was 82 square meters. This includes about 30 square meters of adjacent macadam added to this survey unit for completeness in coverage and not including about 7 square meters of surface that was holes in the surface filled with soil. All of the 82 square meters of macadam was scanned. This results in approximately 82 square meters actually scanned in the 82 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 82 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found with the 43-37 in MA8-12.

6.7.2 Fixed point measurements Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-12 had results in excess of the adjusted surrogate DCGLw. The table below (Table 8) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

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Table 8 - Fixed point results for MA8-12 Point Gross Number beta cpm 1 408 2 344 3 450 4 296 5 369 6 419 7 369 8 399 9 1 326 10 387 11 381 Mean 377 Std Dev 43.6 Min 296 Max 450 6.8 Survey Unit MA8-13 6.8.1 Scan survey Scan measurements were made on the residual macadam in part of 1 grid using the 43-37 detector with an MDCscan of 7311 dpm/l1OOcm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table I on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/l1OOcm 2 (table I on page 3 of appendix B). Inthis case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

Design estimate of the area of the survey unit was 100 square meters. The estimate of the area from the survey was 83 square meters, not including about 4 square meters of surface that was holes in the surface filled with soil. All of the 83 square meters of macadam was scanned. This results in approximately 83 square meters actually scanned in the 83 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class I survey units.

The scans conducted in all 83 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found with the 43-37 in MA8-13.

6.8.2 Fixed point measurements 18 of 27

Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-13 had results in excess of the adjusted surrogate DCGLw. The table below (Table 9) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

Table 9 - Fixed point results for MA8-13 Point Gross Number beta cpm 1 450 2 343 3 313 4 318 5 371 6 370 7 370 8 313 9 366 10 390 11 358 Mean 360 Std Dev 39.8 Min 313 Max 450 6.9 Survey Unit MA8-16 6.9.1 Scan survey Scan measurements were made on the residual macadam in part of 3 grids using the 43-37 GFPC detector with an MDCscan of 7311 dpm/1OOcm 2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table 1 on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/1OOcm 2 (table I on page 3 of appendix B). In 19 of 27

this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

The area of the survey unit was 93 square meters. All of the 93 square meters was actually scanned in the 93 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class 1 survey units. The scans conducted in all 93 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found with the 43-37 in MA8-16.

6.9.2 Fixed point measurements Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the design fixed point measurements in MA8-16 had results in excess of the adjusted surrogate DCGLw. The table below (Table 10) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

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Table 10 - Fixed point results for MA8-16 Point Gross Number beta cpm 1 327 2 352 3 389 4 343 5 342 6 350 7 337 8 496 9 376 10 411 11 346 Mean 370 Std Dev 48.7 Min 327 Max 496 6.10 Survey Unit MA8-17 6.10.1 Scan survey Scan measurements were made on the residual macadam in part of 2 grids using the 43-37 GFPC detector with an MDCscan of 7311 dpm/1 00cm2 (table 3 on page 5 of appendix B). The 75 % administrative limit was 19834 dpm/1OOcm 2 (table 1 on page 3 of appendix B), and the adjusted surrogate Cs137 DCGLw for this survey unit was 26445 dpm/1OOcm 2 (table I on page 3 of appendix B). In this case, the MDCscan was below the DCGLw so no fixed point number adjustment was needed.

The area of the survey unit was 58 square meters. All of the 58 square meters was actually scanned in the 58 square meter survey unit, or 100 percent, which is consistent with coverage requirements for Class I survey units. The scans conducted in all 58 square meters did not identify any activity greater than the action level. The action level was >2900 gross cpm for the 43-37 (table 3 on page 5 of appendix B). No area greater than 2900 gross cpm was found with the 43-37 in MA8-17.

6.10.2 Fixed point measurements Eleven randomly selected fixed point measurement locations were defined for the survey unit, based on a conservative relative shift of about 3.0. None of the 21 of 27

design fixed point measurements in MA8-17 had results in excess of the adjusted surrogate DCGLw. The table below (Table 11) shows the gross beta results for each fixed point measurement, along with the mean, standard deviation and range of the fixed point measurement data.

The standard deviation of the measurements collected from the survey unit was greater than the variability assumed in the survey design. However, since the LBGR used for the design was higher than the typical 50% of the DCGL, a relative shift of three would still result from the observed variability and a slightly less conservative LBGR. Therefore, the assessment of variability, relative shift, and number of fixed point measurements required is consistent between the survey design and the survey results. Based on this, no changes to the survey design or additional measurements are required.

Table 11 - Fixed point results for MA8-17 Point Gross Number beta cpm 1 344 2 360 3 365 4 376 5 489 6 375 7 334 8 384 9 431 10 386 11 327 Mean 379 Std Dev 46.3 Min 327 Max 489 7.0 Data Assessment 7.1 Assessment Criteria The final status survey data has been reviewed to verify authenticity, appropriate documentation, quality, and technical acceptability. The review criteria for data acceptability are:

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1) The instruments used to collect the data were capable of detecting the radiation of the radionuclide of interest at or below the investigation levels.

2) The calibration of the instruments used to collect the data was current and radioactive sources used for calibration were traceable to recognized standards or calibration organizations.

3) Instrument response was checked before and, when required, after instrument use each day data was collected.

4) Survey team personnel were properly trained in the applicable survey techniques and training was documented.

5) The MDCs and the assumptions used to develop them were appropriate for the instruments and the survey methods used to collect the data.

6) The survey methods used to collect the data were appropriate for the media and types of radiation being measured.

7) Special instrument methods used to collect data were applied as warranted by survey conditions, and were documented in accordance with an approved site Survey Request procedure.

8) The custody of samples that were sent for off-site analysis were tracked from the point of collection until final results were provided.

9) The final status survey data consists of qualified measurement results representative of current facility status and were collected in accordance with the applicable survey design package.

If a discrepancy existed where one or more criteria were not met, the discrepancy was reviewed and corrective action taken (as appropriate) in accordance with site procedures.

The statistical test does not need to be performed for this final status survey since the data clearly show that the survey unit meets the release criteria because all measurements in the survey units are less than or equal to the DCGLw.

7.2 Summary of Overall Results MA8-6 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

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MA8-7 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-8 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-9 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-10 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-11 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Twelve fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-12 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-13 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-16 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

MA8-17 had no alarm points during scan surveys of 100% of the surface. Scan MDCs were adequate. Eleven fixed point measurements were all less than the DCGLw. Scan fraction and number of fixed point measurements meets LTP and MARSSIM requirements.

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7.3 Survey Variations (Design, survey request, LTP) 7.3.1 Several survey units had small adjacent macadam surfaces added during the survey to ensure completeness of 6overage of the macadam, specifics discussed throughout the report above.

7.3.2 Several survey units had small areas within the macadam areas that did not have any macadam surface but were exposed soil, specifics discussed throughout the report above.

7.3.3 Twenty nine fixed point locations were relocated up to six feet (typically about 3 feet) to place the points on macadam when the design location of the point fell on a soil hole or at soil along and uneven edges in the pavement which could not be completely accounted for in the initial design layout. These relocations were made in accordance with flexibility intended in the survey design and do not significantly affect the randomness and quality of the design. Points relocated are: five in MA8-6, four in MA8-8, two in MA8-9, six in MA8-10, three in MA8-11, two in MA8-12, four in MA8-13, and three in MA8-16.

7.4 QC comparisons 7.4.1 Scan surveys Multiple locations throughout the several survey units were partially rescanned as QC duplicates. The QC rescans did not identify any activity above alarm points and so are in agreement with the primary scans. QC scans were conducted on 92m2 of the survey unit using the 43-37 GFPC, which represents about 12 percent of the 760 m2 area scanned with the 43-37. This exceeds the minimum 5% required.

7.4.2 Fixed Point measurements One fixed point measurement from each of the ten survey units received QC duplicate GFPC measurements. These duplicates had good agreement as shown in the table below (Table 12) because they support the same conclusion, that the survey units pass. Ten QC splits out of 111 measurements represents about 9.0% and exceeds the 5% minimum criterion.

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Table 12 - QC Fixed point duplicate comparison Fixed Point Result QC Result (cpm) (cpm)

MA8-6 3 375 428 MA8-7 1 304 283 MA8-8 2 276 394 MA8-9 1 293 401 MA8-10 6 321 322 MA8-11 7 296 343 MA8-12 5 300 376 MA8-13 2 280 349 MA8-16 1 263 381 MA8-17 1 301 428 8.0 Final Survev Conclusions The macadam pavement surfaces in OLI final status survey was performed in accordance with the SNEC LTP, site procedures, design calculations, and Survey Request requirements. FSS data was collected to meet and/or exceed the quantity specified or required for each survey unit design. The survey data for each survey unit meets the following conditions:

1) The average residual radioactivity on the surfaces is less than the derived surrogate DCGLw in all of the survey units.

2) All measurements were less than the DCGLw in all of the survey unit areas.

These conditions satisfy the release criteria established in the SNEC LTP and the radiological criteria for unrestricted use given in IOCFR20.1402.

Therefore it is concluded that the SNEC Surface Area consisting of nine survey units of surface exposed macadam pavement in the OLI area and designated MA8-6, MA8-7, MA8-8, MA8-9, MA8-10, MA8-11, MA8-12, MA8-13, MA8-16, and MA8-17 are suitable for unrestricted release.

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9.0 References 9.1 SNEC Facility Site area grid map Drawing number SNECRM-020 9.2 SNEC procedure E900-ADM-4500.60 'Final Status Survey Report" 9.3 SNEC License Termination Plan 9.4 NUREG 1575 'Multi-Agency Radiation Survey and Site Investigation Manual" (MARSSIM), revision 1 August 2000 9.5 COMPASS computer program, Version 1.0.0, Oak Ridge Institute for Science and Education 9.6 Visual Sample Plan 9.7 SNEC procedure E900-IMP-4500.59, "Final Site Survey Planning and DQA" 9.8 SNEC procedure E900-IMP-4520.04, 'Survey Methodology to Support SNEC License Termination" 9.9 SNEC Survey Request (SR) # SR234 9.10 SNEC Survey Request (SR) # SR235 9.11 SNEC Survey Request (SR) # SR236 10.0 Appendices Appendix A - SNEC Calculation E900-05-015 "OL1 Paved and Miscellaneous concrete surfaces MA8, PFI, DB5, DB1 - Survey Design" (11 pages plus numerous attachments)

Appendix B - SNEC Calculation E900-05-015 Rev 1 OL1 Paved and Miscellaneous concrete surfaces MA8, PF1, DB5, DB1, SS12, SS24 - Survey Design" (13 pages plus numerous attachments) 27 of 27