ML082620116

Final Status Survey Report - Fourth Submittal

ML082620116
Person / Time
Site:	Rancho Seco
Issue date:	07/31/2008
From:	Redeker S Sacramento Municipal Utility District (SMUD)
To:	Document Control Desk, NRC/FSME
References
MPC&D 08-064
Download: ML082620116 (20)

Text

SMUD

!r SACRAMENTO MUNICIPAL UTILITY DISTRICT The Power To Do More.

P.O. Box 15830, Sacramento, CA 95852-1830; 1-888-742-SMUD (7683)

MPC&D 08-064 July 31, 2008 U.S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555 Docket No. 50-312 Rancho Seco Nuclear Generating Station License No. DPR-54 RANCHO SECO FINAL STATUS SURVEY REPORT - FOURTH SUBMITTAL Attention: John Hickman Attached is the Final Status Survey (FSS) Report for several of the Rancho Seco survey units.

Specifically, this submittal addresses dismantlement and FSS information for the survey units associated with the 800001, 800010, 812000, 813000, 826000, 848000, 854000, and 899000 areas. Table 1 of the FSS Report provides a description of the survey units addressed in this submittal. The report provides a summary of the survey results and concludes that survey units covered in this report meet the radiological criteria for unrestricted use.

Members of your staff with questions requiring additional information or clarification may contact Bob Jones at (916) 732-4843.

Sincerely, Steve Redeker Manager, Plant Closure & Decommissioning Cc w/ attachment: NRC Region IV RANCHO SECO NUCLEAR PLANT - 14440 Twin Cities Road, Herald, CA 95638-9799; (209) 333-2935

RANCHO SECO FSS FINAL REPORT Final Status Survey Report 4 July 31, 2008 I

FSS FINAL REPORT Final Status Survey Report 4 10 Overview As discussed in Section 1.4 of the Rancho Seco License Termination Plan (LTP), SMUD intends to release the Rancho Seco site for unrestricted use in two phases, with the license being terminated after completion of the second phase. The first phase includes the release of the majority of the site, including impacted and non-impacted areas, except for the Interim Onsite Storage Building (IOSB) and the area immediately surrounding it.

Once an area has been verified as ready for release, no additional surveys or decontamination of the area will be required unless the controls (e.g., administrative or engineered) established to prevent re-contamination have been compromised.

SMUD will continue to store Class B'& C radioactive waste in the IOSB until an acceptable disposal facility becomes available. After disposing of the Class B & C radioactive waste, SMUD will complete the final status survey for the remainder of the site (i.e., the area immediately surrounding the IOSB) and will submit a license amendment request to terminate the 10 CFR Part 50 license and release the remainder of the site for unrestricted use. The spent nuclear fuel and the Greater than Class C (GTCC) waste are stored at the Rancho Seco Independent Spent Fuel Storage Installation (ISFSI),

which is licensed under 10 CFR Part 72, independent of the 10 CFR Part 50 licensed site.

Section 1.4 of the LTP discusses the information to be provided to support release of land from the Rancho Seco 10 CFR Part 50 license. The information provided in this report includes a discussion of dismantlement activities performed, final status survey results, and an evaluation of the potential for re-contamination and controls applied to prevent this for each survey unit completed.

The information contained in this submittal, together.with the information to be provided in subsequent FSS reports, will be sufficient for the NRC to conclude that, for the land and structures associated with the release, dismantlement has been performed in '

accordance with the approved license termination plan, and the terminal radiation survey and associated documentation demonstrates that the facility and site are suitable for release in accordance with the criteria for decommissioning in 10 CFR Part 20, Subpart E by meeting a site release criterion of 25 millirem TEDE per year over background.

Once these lands and structures are released, no additional surveys or decontamination of these areas will be required unless the NRC determines that the criteria of 10 CFR Part 20, Subpart E were not met.

2

2.0 Site Information and Physical Description 2.1 Physical Description of Land or Structures to be Released The land and structures to be released will be described in the application for license amendment and is unchanged by this submittal.

2.1.1 Survey Unit Information Included in This Submittal As discussed in section 1.0 above, this submittal provides detailed discussion on demolition activities completed and final status survey results for 63 survey units located on the site to be released. Details are provided for each survey unit on survey methods, results, data analysis, and conclusions. Additional information on all other applicable survey units for the site will be provided in subsequent submittals. In all cases, Rancho Sedo is providing a complete package of information relating to each survey unit so that the NRC staff can verify that the License Termination Plan has been fully implemented for each survey unit and that the final status survey results support unrestricted release of the land from License DPR-54 in accordance with the proposed license amendment.

This submittal addresses dismantlement and FSS information for survey units associated with the 800001, 800010, 812000, 813000, 826000, 848000, 854000, and 899000 areas. Table 1 provides a description of the survey units addressed in this submittal.

Table 1 Survey Unit Class General Description of Survey Unit 800001 Helo Pad Area- The Helo Pad Area was a large F800001 3 paved and unpaved area located on the south side of the industrial area of the site. The area is 17284 m'.

8000103 Aux Bldg-NSEB (Pigeon) Alley- The Alley was F8000103 3 a paved area located between the Auxiliary Building. south wall and the NSEB. The area was 443 rn2.

Typically 812000 Fuel Building- The Fuel Building contained the class 1 spent fuel storage pool and the floor area and upper walls floor, lower surrounding the pool. The surveys presented in this F812000 walls and submittal are for the following locations: Fuel Building class 2 exterior walls and Cask Catcher Pad.

upper walls, ceiling Typically 813000 Auxiliary Building- The Auxiliary Building class 1 contained the systems used to transport, process and floor, lower contain radioactive solids, gases and liquids. The surveys walls and presented in this submittal are for the following rooms class 2 located on the -20', +20', and grade elevation: 01 upper stairs,02 stairs, 10,15,36,51,52,56,102-103,106,107,109-walls, 110,117,127,133,134,138,209,210,212-226,318,319,320-ceiling 324,346-elevator, 351, and the roof.

3

Survey Unit Class General Description of Survey Unit 826030 Turbine Deck-The Turbine Deck was the concrete F826030 support structure for the turbine-generator. It was located on the 40' elevation of the Turbine Building. The area is 2

2615 mn .

848019 Retention Basin Misc Small Buildings- The Retention Basin Small Buildings housed the electronic controllers and the chlorination controls for the Retention Basins. The area was 242 mn.

8540001, 2 Misc Small Buildings- The Small Buildings F8540001,2 3 contain the lubricating fluids and lawn maintenance equipment. The total area is 390 mn.

8990421,422,423 kadwaste Pipe- The Radwaste Pipe was F8990421,422, 1 the embedded drain pipes which collected radwaste from 423 the various floor drains and sumps and routed it to the waste processing systems. The total area is 130m 2 .

Note: The locations of the survey areas listed in Table 1 above are shown in Fig. 1.

2.1.2 Survey Unit Information Being Provided in Subsequent Submittals As discussed previously, Rancho Seco anticipates at least one additional submittals of detailed information on dismantlement activities and final status survey results as these activities are completed. Several survey units listed in Submittal 3 for Submittal 4 have not been included. These are:

F8000091 SE Industrial Area F8000101,2 Industrial Area Yard Area F8130371 Aux Bldg Room 51 e F8370001 RHUT, Aux Boiler Pad Because some dismantlement activities could potentially affect these completed survey units additional surveillance and surveys are conducted until dismantlement activities can no longer pose any impact to the survey unit(s). Once potentially compromising conditions are mitigated for these survey units and final conditions documented the final status survey summary reports will be submitted. Below is a list of the remaining survey areas to be surveyed and submitted.

The schedule and content of each submittal were developed based on a review of the remediation and FSS schedule, as well as in consideration of NRC review requirements. The remediation schedule is dynamic and subject to continued refinement in logic, durations, and completion dates.

It is Rancho Seco's intent to maintain the basic submittal schedule provided below. However, as a result of remediation schedule changes, it is possible additional submittals may be made with the goal of providing release records as soon as possible to the NRC to facilitate the agency's timely review.

4

Fifth Submittal Scheduled for 10/16/08 (-90 Survey Units)

F8000091 SE Industrial Area F800001,2 Industrial Area Yard (2 Survey Units)

F8000142 North IA Pavement F800011 Central Corridor F808003 Cooling Tower Buffer Area F810001 Tank Farm Surface Soil F810002 Tank Farm Subsurface Soil F811000 Reactor Building (-24 Survey Units)

F812000 Fuel Building (-14 Survey Units)

F813000 Auxiliary Building (-41 Survey Units)

F826000 Turbine Building (-22 Survey Units)

F826025 North Laydown Area F826026 South Laydown Area F834000 Rail Land (2 Survey Units).

F8370001,2 RHUT, Auxiliary Boiler-Pad (2 Survey Units)

F501005 Access Road F8990098 CDS Cross-Ties F899011 Decay Heat System Pipe F899040 Reactor Drain System Pipe F899044 Fuel Pool System Pipe 2.2 Dismantlement Activities The Rancho Seco License Termination Plan describes the dismantlement activities to be performed for each area and applicable structure of the Rancho Seco site consistent with the use of the Building Occupant scenario. In general, the LTP indicates that temporary structures will be demolished and that permanent structures will be left standing following final survey. In addition, the ISFSI and IOSB structures will remain. During the period of time represented by this submittal, concrete remediation has been completed in the Auxiliary Building, Turbine Building, and Spent Fuel Building. Interior concrete removal is completed in the Reactor Building. The Reactor liner plate is being cleaned and removal of metal interferences is ongoing. The liner plate beneath reactor vessel will be removed and activated concrete will be remediated.

3.0 Technical Evaluation 3.1 Potential for Cross-Contamination from Subsequent Activities Since decommissioning activities are being conducted onsite in parallel with final status survey and release decisions, measures must be taken to protect survey areas from contamination during and subsequent to the final status survey.

Rancho Seco LTP sections 3.3.5 and 5.2.4 describe contamination and access control measures and periodic routine monitoring practices to prevent and/or detect re-contamination of survey areas during or following FSS. These 5

requirements are implemented, as appropriate, through established procedures as described in the LTP.

The potential for re-contamination and the contamination controls/monitoring for the specific survey areas included in this release phase are discussed and evaluated below:

3.1.1 800001 Helo Pad This area consists of a large portion of the south industrial area, both paved and unpaved. It combined the Folsom Intake, the Helo Pad, and the south Scrap Yard which were all Class 3 areas. It was successfully surveyed as a Class 3 area. No remediation was required. There is little likelihood that the area will become contaminated in the future.

3.1.2 8000103 Aux Building-NSEB (Pigeon) Alley The Alley was successfully surveyed as a Class 3 area. No remediation was required. No radioactive material is allowed in the area and there is little likelihood that it will become contaminated in the future.

3.1.5 8120011, 13, 15, 16 Fuel Building The Fuel Building required extensive remediation in the spent fuel pool area. The pool was isolated and extensive contamination controls were applied. The structure exterior was successfully surveyed. The interior area surveys are currently ongoing. The areas where surveys have been completed have been placed under periodic surveillance to detect any potential re-contamination.

.3.1.7 813000 Auxiliary Building (zones 1-12)

The rooms in zones 1-6 of the Auxiliary Building surveys are some of the most contaminated site areas. The survey units are all classified at least Class 2 for upper walls/ceilings with floors being at least Class 2 but usually Class 1. Most of the lower walls and floors required some concrete remediation. When remediation was ongoing in adjacent areas, through-wall penetrations were covered, drain pipe openings were plugged, strict access controls were maintained and the areas are subject to periodic surveillance to check for potential re-contamination. Portions of zones 7-12 are Class 2 or 3 with little potential for re-contamination and the controls were somewhat less rigorous.

3.1.8 826000 Turbine Building The Turbine Building was successfully remediated and surveyed.

No radioactive material is allowed in the area and there is little likelihood that it will become contaminated in the future. The area 6

has been placed under periodic surveillance to detect any potential re-contamination.

3.1.10 848019 Misc Small Buildings (Retention Basin)

The Small Buildings were successfully surveyed as a Class 3 area.

No remediation was required. No radioactive material is allowed in the area and there is little likelihood that it will become contaminated in the future. The area has been placed under periodic surveillance to detect any potential re-contamination.

3.1.11 8540001, 2 Misc Small Buildings (POL and Lawn Maintenance)

The Miscellaneous Small Buildings were successfully surveyed as' Class 3 structures. No remediation was required. There is little likelihood that the area will become contaminated in the future.

The area has been placed under periodic surveillance to detect any potential re-contamination.

3.1.12 899000 Buried or Embedded Piping Systems The pipe remaining on site is surveyed and grit blasted, if necessary, to remove surface contamination. Once final surveys are complete, the pipes are plugged to prevent recontamination or, if necessary, grouted in place. There, is little likelihood that piping will become re-contaminated following final survey. In addition, the rooms containing access to the pipes are placed under periodic surveillance to detect any potential re-contamination once FSS is complete.

4.0 Final Status Survey Report Rancho Seco LTP section 5.7.3 identifies the contents of the written reports of final status survey results that are to be submitted to the NRC. The contents include the items described in NUREG-1757, Vol. 2, Section 4.5. The survey unit design details and results are provided below in summary fashion. Specific survey unit design details and results are provided in a copy of each survey unit summary report in Attachment 1.0 of this submittal.

4.1 Overview of Results The following survey units are included in this report:

F800001 Helo Pad Area F81201 11 Cask Catcher Pad F812013, 15, 16 Fuel Building F8000103 Aux Building-NSEB (Pigeon) Alley F8260303, 4, 5 Turbine Building F848019 Misc Small Buildings (Retention Basin)

F8540001, 2 Misc Small Buildings (POL, Lawn Maintenance) 7

F813000 Auxiliary Building (Rooms 01 stairs, 02 stairs, 10, 15, 36, 51, 52, 56, 102-103, 106, 107, 109-110, 117, 127, 133,134, 138, 210, 212-226, 318, 319, 320, 321, 322-24, 346 elevator, 351, and the roof.)

F8990421, 422, 423 Radwaste Piping The summary report for each survey unit contains a description of the survey unit; design information, including classification, size, number of measurements, map, scan coverage, and DCGL; survey results; survey unit investigations (anomalous data); data assessment results, including statistical evaluations, if applicable; changes. in initial survey unit assumptions on extent of residual activity, an evaluation of LTP changes subsequent to the FSS of the survey unit and survey unit conclusions.

Overall, the attached survey unit summary reports demonstrate that the survey units meet the criteria for release for unrestricted use in accordance with the NRC approved Rancho Seco License Termination Plan.

4.2 Discussion of Changes to FSS Program The purpose of this section is to discuss changes to the FSS program. At the time of this submittal Revision 1 of the LTP has been submitted to the NRC. The changes were mostly editorial in nature and with the exception of a clarification of pipe grouting criteria, there were no changes made to the FSS Program that impacted the final surveys 4.3 Final Status Survey Methodology This section summarizes the implementation of the LTP Final Status Survey methodology for the survey units that are included in this report supporting the release of remaining non-ISFSI and non-IOSB land. A table is provided below that lists the key FSS design features for each survey unit. These design features include the survey unit classification and size, the standard deviation and Lower Boundary of the Gray Region (LBGR) used for determining the number of direct measurements taken, the percent scan coverage, the design DCGLEMC and the number of measurements required. This report covers only structures for which the DCGL is 43,000 dpm/100 cm 2 (16,000 dpm/100 cm 2 for special areas) as well as pipe which has a DCGL of 100,000 dpm/100 cm 2 and soil or paved areas which have a DCGL of 52.6 pCi/g Cs-137sur and 12.6 pCi/g Co-60. The standard deviations listed were obtained from site characterization data or survey unit specific measurements. The Type 1 and 2 Errors are the default values of 0.05 and the LBGR is initially based on 50% of the DCGL.

Table 2 Survey Unit Design Parameters SurveySurvy Cass Unit Size Survey Deviations Standard Design Number of %LSca (m2 ) Deviation DCGLEMC Measurements % Scan Unit ID F8000011 Helo Pad Area 1 3 17,284 0.10 26.3 N/A pCi/g 14 6.5 8

Survey Standard Design Number of Survey Class Unit Size LBGR Units  % Scan Unit ID (in2 ) Deviation DCGLEMc Measurements F8000103 Aux Building -NSEB (Pigeon) Alley 3 3 443 0.118 26.3 N/A pCi/g 14 28 F8 120111 Cask Catcher Pad 1 1 103 437 41,689 137,600 dpm/1002 15 100 cm F8120131 Fuel Building West Ext Wall 1 2 322 747 40,759 N/A dpm/100 cm2 19 68 F8120151 Fuel Building East Ext Wall dpm/ 100 1 2 332 747 40,759 N/A cm/2 14 39 F8120161 Fuel Building East Ext Wall 1 1 123 747 40,759 154,800 dpm/1 cm2 2 00 23 100 F8130071 Aux Building Room 02 Stairs 1 1 208 9,976 21500 154,800 dpm/ 1 00 33 100 Scm2 F8130081 Aux Building Room 01 Stairs 1 1 217 1 9,976 21,500 154,800 dpm/100 cm2 33 100 F8130091 Aux Building Rooms 56, 127, 138 1 3 178.1 1 6,935 21,500 N/A ~cm2 dpm/200 0 14 11 F8130101 Aux Building Room 10 1 1 57.4 9,976 21,500 223,802 dpm/100 cm2 20 100 F8130102 Aux Building Room 10 2 2 239.4 9,976 21,500 N/A dpm/100 cm2 1557 70 F8130151 Aux Building Room 15 1 1 238 12,035 21,500 152,357 dpm/100 34 100 cm F8130161 Aux Building Room 15 1 1 310.1 12,035 21,500 153,867 cm2410 dpm/200 45 F8130171 Aux Building Room 15 1 1 309.9 12,035 21,500 153,866 dpm00 cm2410 45 100 F8130421 Aux Building Room 36 I 1 144.1 15.9 26.3 153 cm2 dpm/00 21 2 100 0

F8130431 Aux Building Room 36 301.1 10,204 21,500 154,566

. ~cm2 dpm200 44 100 F8130441 Aux Building Room 36 164.6 10,204 21,500 154,285 dpm100 cm2 24 100 F8130451 Aux Building Room 36 1 1 247.3 10,204 21,500 154,145 dpm/100 cm2 36 100 F8130461 Aux Building Room 36 1 1 159.6 10,204 21,500 153,313 dpm200 cm2 23 100 9

Su Sunitey as Clas Survey Unit Size Standard LBGR Design UisSa Units Number of  % Scan 2

Unit ID (i ) Deviation DCGLEMc Measurements F8130471 Aux Building Room 36 dpmIlIOO 4 1 1 280.9 10,204 21,500 154,370 cm 0100 F8130691 Aux Building Room 51 1 1 125 12,035 21,500 154,800 dpml100 18 100 cm2 F8130701 Aux Building Room 51 I 1 202 12,035 21,500 150,500 dpm/lO0 100 cm9 F8130711 Aux Building Room 51 1 140 12,035 21,500 150,500 dpmi/100 cm2 20 100 F8130721 Aux Building Room 51 1 1 220 12,035 21,500 154,800 dpm/1 cm22 00 32 100 F8130732 Aux Building Room 51 1 1 93 12,035 21,500 176,300 dpm/IOO 17 100 Icm1 F8130741 Aux Building Room 52 1 1 288 12,035 21,500 154,800 dpmI/00 42 100 cm2 F8130751 Aux Building Room 52 dpmIlOO 1 1 177 12,035 21,500 154,800 cm 26 100 F8130761 Aux Building Room 52 1 1 150 12,035 21,500 154,800 dpmr1 2 00 22 100 cm F8130771 Aux Building Room 52 1 1 214 12,035 21,500 154,800 dpm/100 cm2 31 100 F8130861 Aux Building Rooms 102, 103 1 2 246 6,935 21,500 N/A dpm/100 cm2 14 65 F8130862 Aux Building Room 106 1 1 296.5 6,935 21,500 150,500 dpm100 cm2 42 100 F8130931 Aux Building Room 107 1 2 146 12,035 21,500 N/A cm 2 dpm/100 17 29 F8130941 Aux Building Rooms 109, 110 1 2 898.3 6,935 21,500 N/A dpm/1002 14 23 cm F8131041 Aux Building Room 117W 716 6,935 21,500 N/A c2 cm dpm/100 14 26__

F8131051 Aux Building Room 117E 1 2 566.5 6,935 21,500 N/A dpm/1 00 c214 48 I cm, 0 F8131221 Aux Building Room 133 1 1 271.1 6,935 21,500 154,800 dpm/100 100 cm2 F8131222 Aux Building Room 133 2 2 270.9 6,935 21,500 N/A dpl00143 cm2 14 33 10

SurveySurey Clss Unit Size Survey ILBGR Standard Design UisSa Number of l U (i 2 ) Deviation DCGLEMc Measurements % Sean Unit ID F8131231 Aux Building Room 134 1 1 260 6,935 21,500 154,800 dpmn/l00 38 100 cm, F8131381 Aux Building Room 209 1 184 5,461 21,500 154,800 dpm/1200 27 100 cm2 F8131382 Aux Building Room 209 1 1 312 5,461 21,500 154,800 dpm/I00 45 100 cm2 F8131402 Aux Building Room 210 2 2 205 5,461 21,500 N/A dpm/I00 14 25 cm2 F8131403 Aux Building Room 210 3 1 83 6,935 21,500 167,700 dpm/100 14 100 cm, F8131411 Aux Building Rooms 212-226, fan pedestals 2

1 3 4,546 243 21,500 N/A dpm/1 cm 00 14 5 F8131561 Aux Building Roof 1 3 1,434 136 21,500 N/A dpm/10 14 11 0 4cm F8131781 Aux Building Room 319 1 1 85 3627 21,500 167,703 dpm/ 1 00 14 100 cm2 F8131782 Aux Building Room 319 132 3,627 21,500 N/A dpm/100 cm2 14 48 F8131791 Aux Building Rooms 320 Lower 1 2 59 3,627 21,500 N/A cm 2 dpm/100 15 25 F8131792 Aux Building Room 320 Upper, Room 321 2 3 273 227 21,500 N/A cm 2 dpm/100 14 22 F8131811 Aux Building Rooms 322-324, 351 1 3 853 3,627 21,500 N/A dpm/100 14 16 cm0 F8131812 Aux Building Rooms 322-324, 351 2 3 283 3,627 21,500 N/A cm 2 dpm/100 14 10 F8132051 Aux Building Rooms 346, elevator 1 3 195.6 261 21,500 N/A cm 2 dpm/00 114 F8132131 Aux Building Exterior 310.7 342 21,500 N/A cm12 14 34 F8132141 Aux Building Exterior 698.6 342 21,500 N/A cm/2 14 38 F8132142 Aux Building Exterior South Wall 1 3 426.6 342 21,500 N/A dpm/100 cm2 14 27 F8260303 Turbine Building Deck North 2 815 1,723 37,831 N/A dpm/100246 cm22m/2 24 60 3~~

11

ass Survey Standard Design Number of Unit ID Size Deviation LBGR DCGLc Measurements Scan

_________ ~(in 2

) DCLM F8260304 Turbine Building Deck Center 4 2 953 1,723 37,831 N/A 2 dpm/100 16 73 cm F8260305 Turbine Building Deck South 5 2 847 1,723 37,831 N/A dpm/100 21 28 cm2 F8480019 Misc Small Buildings (Retention Basin) 9 3 9 242 431 21,500 N/A ~~dpm/I0O dr/2 cm2 43 14 31 F8540001 Misc Small Buildings (POL) 1 3 260 495 21,500 N/A dpm/100 cm2 14 14 F8540002 Misc Small Buildings (Lawn Maintenance) 1 3 130 3

495 21,500 N/A

~~dpm/O0 cm2 1

14 1

11 F8990421 Radwaste Pipe 1 1 89 100,000 50,000 100,000 dpm/100 1898 100 cm2 F8990422 Radwaste Pipe 2 1 30.4 100,000 50,000 100,000 dpm/100 696 100 cm2 F8990423 Radwaste Pipe 3 1 10.7 100,000 50,000 100,000 dpm/100 393 100 cm 4.4 Final Status Survey Results The methods used to determine the number of direct measurements to be taken is described in the LTP and the specific survey unit summary reports provided in . Key survey results are given in Table 3 below.

Table 3 Survey Unit FSS Results 12

Scan No. Direct Mean Maximum Direct No. Scan Measurement Measurements. Direct Direct Standard Units Elevated Range Taken Result Result Deviation Areas F8130071 Aux Building Room 02 Stairs 1,482-458,279 33 2,186 5,405 1,067 dpmn100 cm2 13 F8130081 Aux Building Room 01 Stairs 1,825-1,750,044 33 1,754 6,583 1,014 dpm/100 cm 2 5 F8130091 Aux Building Rooms 56, 127, 138 2,912-7,175 14 1,354 2,505 348 dpm/100 cm2 0 F8130101 Aux Building Room 10 2,793-79,976 20 1,974 3,792 712 dpm/100 cm2 0 F8130102 Aux Building Room 10 2,067-31,442 17 1,624 2,080 205 dpm/100 cm 2 0 F8130151 Aux Building Room 15 2,389-1,470,949 43 1,734 9,104 1,343 dpm/100 cm2 4 F8130161 Aux Building Room 15 1,482-54,498 47 1,819 5,239 705 dpm/100 cm2 7 F8130171 Aux Building Room 15 2,460-43,561 45 1,514 2,469 247 dpm/100 cm 2 0 F8130421 Aux Building Room 36 10,992-46812* 21 0.164 0.557 0.156 dpm/100 cm 2 17 F8130431 Aux Building Room 36 1,895-35,630 47 1,565 3,284 352 dpm/100 cm2 0 F8130441 Aux Building Room 36 1,966-666,520 39 1,916 4,124 598 dpm/100 cm 2 15 F8130451 Aux Building Room 36 2

1,476-83,600 39 2,676 7,724 1,234 dpm/l00 cm 3 F8130461 Aux Building Room 36 3,829-5,550,920 36 2,433 7,081 1,172 dpm/100 cm 2 F8130471 Aux Building Room 36 2

2,409-71,800 2943 1,867 6,795 1,045 dpmL/100 cm 0 F8130691 Aux Building Room 51 3,276-140,042 2 8 3,164 11,609 28521 dpm/100 cm 2 F8130701 Aux Building Room 51

.2,167-137,563 29 3,340 "47,614. 8,600 dpm/

- 100 cm2 0 F8130711 Aux Building Room 51 2,993-523,819T 22 2,380 4,648 847 dpm/ 100 cm2 I 13

Scan No. Direct Mean Maximum Direct No. Scan Measurement Measurements. Direct Direct Standard Units Elevated Range Taken Result Result Deviation Areas F8130721 Aux Building Room 51 2,490-171,029 32 1,971 4,466 551 dpm/100 cm 2 F8130732 Aux Building Room 51 2

3,196-48,932 25 2,633 15,100 2,879 dpm/100 cm 0 F8130741 Aux Building Room 52 2

1,790-14,657 43 1,559 2,246 230 dpm/100 cm 0 F8130751 Aux Building Room 52 2,409-116,993 31 2,198 7,610 1,240' dpm/100 cm 2 0 F8130761 Aux Building Room 52 4,225-999,149 22 2,018 3,470 455 dpm/100 cm 2 3 F8130771 Aux Building Room 52 2,274-47,679 / 31 1,621 3,927 486 dpm/100 cm2 0 F8130861 Aux Building Rooms 102, 103 1,459-25,067 14 3,106 3,737 464 dpm-l10 cm2 0 F8130862 Aux Building Room 106 1,834-487,881 43 1,426 4,440 561 dpm/100 cm 2 1 F8130931 Aux Building Room 107 8,122-41,544 17 3,929 7,352 1,134 dpm/100 cm 2 0 F8130941 Aux Building Rooms 109, 110 790-18,644 14 3,876 18,364 4,181 dpm/100 cm 2 0 F8131041 Aux Building Room 117W 853-17,846 15 2,535 2,866 357 dpm/100 cm 2 0 F8131051 Aux Building Room 117E 2

1,195-22,272 14 3,505 4,233 407 dpm/100 cm 0 F8131221 Aux Building Room 133 1,419-124,712 41 3,519 22,608 3,292 dpm/100 cm 2 0 F8131222 Aux Building Room 133 1,318-24,396 16 2,431 2,745 230 dpm/100 cm 2 0 F8131231 Aux Building Room 134 1,727-13,001 38 2,810 5,556 566 dpm/100 cm2 0 F8131381 Aux Building Room 209 1,620-66,383T 34 1,648 4,757 719 dpm/100 cm 2 0 F8131382 Aux Building Room 209 1,563-45,196 63 1,666 4,710 489 dpm/100 cm2 0 14

Scan No. Direct Mean Maximum Direct No. Scan Measurement Measurements. Direct Direct Standard Units Elevated Range Taken Result Result Deviation Areas F8131402 Aux Building Room 210 2,575-13,777 14 1,038 1,323 207 dpm/100 cm 2 0 F8131403 Aux Building Room 210 3,110-194,688 14 4,069% 10,395 2,069 dpm/100 cm 2 F8131411 Aux Building Rooms 212-226, fan pedestals 1,548-13,975 14 1,240 1,572 246 dpm/100 cm 2 0 F8131561 Aux Building Roof 2,290-2,470 14 1,509 1,580 54 dpm/100 cm 2 0 F8131781 Aux Building Room 319 1532-731,990 21 2,246 13,902 2,720 dpm/l00 cm 2 8 F8131782 Aux Building Room 319 1,621-5,949 17 1,586 1,836 162 dpm/100 cm 2 0 F8131791 Aux Building Rooms 320 Lower 2,010-2,956 15 1,283 1,618 208 dpm/100 cm 2 0 F8131792 Aux Building Room 320 Upper, Room 321 2,528-5,627 14 1,612 1,743 114 dpm/100 cm 2 0 F8131811 Aux Building Rooms 322-324, 351 1,929-6,155 14 1,404 1,790 209 dpmL/100 cm2 0 F8131812 Aux Building Rooms 322-324, 351 4,057-6,661 F 14 1,774 2,090 200 dpm/100 cm 2 0 F8132051 Aux Building Rooms 346, elevator Insitu338 14 1,421 1,634 224 dpm/100 cm 2 0 F8132131 Aux Building Exterior 1,229-5,847 14 1,597 1,966 289 dpm/100 cm 2 2 F8132141 Aux Building Exterior 5,040-8,194 14 2,730 4,020 646 dpm/100 cm 2 0 F8132142 Aux Building Exterior South Wall 2

848-1,090 14 1,292 1,561 231 dpm/100 cm 0 F8260303 Turbine Deck North

<1,040 24 2,026 2,484 210 dpm/100 cm 2 0 F8260304 Turbine Deck Center 2

<1,420 16 2,040 2,646 343 dpm/100 cm 0 F8260305 Turbine Deck South

<998 21 1,823 2,090 191 dpm/100 cm 2 0 15

Scan No. Direct Mean Maximum Direct No. Scan Measurement Measurements. Direct Direct Standard Units Elevated Range Taken Result Result Deviation Areas F8480019 Misc Small Buildings (Retention Basin) 1,566-5,076 14 914 1,997 484 dpm/100 cm 2 0 F8540001 Misc Small Buildings (POL) 1,601-8,994 14 785 1,899 329 dpm/100 cm 2 0 F8540002 Misc Small Buildings (Lawn Maintenance) 3,448-5,949 14 1,705 2,132 209 dpm/1 00 cm 2 0 F8990421 Radwaste Pipe 1,919-137,654 1898 4,609 137,654 6,930 dpm/100 cm2 F8990422 Radwaste Pipe 1,917-92,283 696 5,692 92,283 5,482 dprm100 cm2 0 F8990423 Radwaste Pipe 1,752-10,368 393 3,929 10,368 1,089 dpm/l100 cm 2 0 4.5 Survey Unit Conclusions Rancho Seco concludes that this information is sufficient for the NRC to make a determination equivalent to 10CFR50.82 (a)(1 1) regarding the survey units contained in this submittal. The surveys for these survey units and associated documentation demonstrate that these areas of the facility and site are suitable for release in accordance with the criteria for decommissioning in 10CFR20, subpart E by meeting a site release criteria of 25 millirem TEDE per year over background for all dose pathways in accordance with the approved License Termination Plan.

As stated in section 4 of the Rancho Seco LTP, as long as the residual activity within a survey unit is less than the DCGL (i.e., the survey unit average activity is less than the DCGL and the EMC criterion has been met), the ALARA criterion has been achieved.

4.6 Revision 1 of Summary Reports for Auxiliary Building Rooms 1, 2, and 3 As part of the corrective action for DQ#07-020, gamma surveys were made in rooms 1 (F8130011), 2 (F8130031), and 3 (F8130051), once remediation was complete in the adjacent areas. The gamma surveys indicated the presence some small elevated areas. In the interest of completeness, those areas were evaluated and added to Table 3-1 of the Summary Reports for the above survey units.

Those revised reports are included in Attachment 1 of this Report.

16

4.7 Survey Unit Data Assessment of Auxiliary Bldg. Rm 18: F8130201 During a confirmatory survey conducted by ORIS, a small particle containing Cs-137 (-0.22 jtCi) was discovered in the floor trench of Room 18. The particle was removed and analyzed. Follow-up surveys were conducted of the trench, the floor and the wall penetrations which failed to reveal any other evidence of recontamination of the area following final survey. Based on the original survey results and the lack of any additional sources of contamination, Room 18 is considered to meet the release criteria and the reported survey reflects the "As left" condition of the room. The corrective actions and follow-up surveys were reported in DQ#7-020.

5.0 References Rancho Seco License Termination Plan, rev. 1, submitted 6/08.

DQ#07-020 "Elevated Activity in Areas Having Already Completed FSS".

17

00 8000D1 FINAL REPORT 4 PRINCIPLE SITE STRUCTURES FIGURE 1

Attachment 1 Survey Unit Summary Reports 19