Text

Release of Non-ISFSI Site Land - Final Status Survey Final Report No. 9A, Revision 0
	ML051370366
Person / Time
Site:	Maine Yankee
Issue date:	05/05/2005
From:	Meisner M; Maine Yankee Atomic Power Co
To:	; Document Control Desk, NRC/FSME
References
	MN-05-020, RA-05-023
	Download: ML051370366 (127)
	v • d • e

Maine Yankee 321 OLD FERRY RD.

WISCASSET, ME 04578-4922 May 5, 2005 MN-05-020 RA-05-023 Proposed Change No. 218, Supplement 21 UNITED STATES NUCLEAR REGULATORY COMMISSION Attention: Document Control Desk Washington, DC 20555

References:

(1) License No. DPR-36 (Docket No. 50-309)

(2) Maine Yankee Letter to the USNRC, MN-02-048, dated October 15, 2002, Revision 3, Maine Yankee's License Termination Plan (3) USNRC Letter to Maine Yankee, dated February 28, 2003, Issuance of Amendment No. 168 to Facility Operating License No. DPR-36 (4) Maine Yankee Letter to the USNRC, MN-04-020, dated March 15, 2004, License Amendment Request: Release of Non-ISFSI Site Land, Proposed Change No. 218

Subject:

Release of Non-1SFSI Site Land - FSS Final Report No. 9A On March 15, 2004, Maine Yankee submitted a request for amendment (Reference No. 4) to the facility operating license (Reference No. 1) pursuant to 10 CFR 50.90 and in accordance with the NRC Approved License Termination Plan (LTP) for Maine Yankee (Reference No. 2), to indicate NRC's approval of the release of the Non-ISFSI site land from the jurisdiction of the license. In support of that request, Maine Yankee supplied the information required in LTP section 1.4.2 and 5.9.3. The land area associated with the license amendment request included the entire non-ISFSI portion of the site land. Maine Yankee is submitting the required dismantlement and survey information for the survey units that make up the non-ISFSI portion of the site land in a phased fashion. Accordingly, Maine Yankee is herewith supplying the dismantlement and survey information for three survey areas comprising four survey units.

Other descriptive information and technical evaluations contained in Reference No. 4 are unaffected by this information and are, therefore, not included in this submittal, as indicated.

Attachment I - Final Status Survey Final Report No. 9A', provides dismantlement and summary survey information for the survey units covered in this submittal and the revised schedule for the submittal of the remaining dismantlement and survey information. Attachment II provides a copy of the supporting final status survey release records for the survey units that make up this phase of survey information.

Maine Yankee requests timely review and acceptance of this dismantlement and survey information.

I Submittal 9A is an additional submittal providing final status survey release records for 4 survey units that were scheduled to be included in Submittal 9, but were delayed pending final review and approval.

PI~

UNITED STATES NUCLEAR REGULATORY COMMISSION Attention: Document Control Desk Page 2 of 2 If you have any questions, please contact me.

Sincerely, Michael J. Meisner Vice President and Chief Nuclear Officer Attachments I. Final Status Survey Final Report No. 9A II. Release Records cc: Dr. R. R. Bellamy, NRC Region I Mr. D. R. Lewis, Esq., Shaw Pittman Mr. C. Pray, State of Maine, Nuclear Safety Advisor Mr. P. J. Dostie, State of Maine, Division of Health Engineering Mr. D. Gillen, NRC Acting Director, Division of Waste Management Mr. M. Rosenstein, USEPA Region I Mr. S. J. Collins, NRC Regional Administrator, Region I Mr. J. Buckley, NRC NMSS Project Manager, Decommissioning Mr. M. Roberts, NRC Region I Mr. R. Shadis, Friends of the Coast

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I

1.0 DESCRIPTION

2 2.0 PROPOSED LICENSE CONDITION ------------------------------------------------- 2

3.0 BACKGROUND

-- -- 33--

4.0 SITE INFORMATION AND PHYSICAL DESCRIPTION ------------------------ 3 4.1 Physical Description of Land to be Released -------------------------------------- 3 4.1.1 Survey Unit Information Included in this Submittal ------------------------- 3 4.1.2' Survey Unit Information Provided in Subsequent Submittals -------------- 5 4.2 Dismantlement Activity -------------------------------------------------------------- 5 4.2.1 FA-0400 Fuel Building ---------------------------------------------------------- 6 4.2.2 FR-0 11 Yard West Excavations ----------------------------------------------- 6 4.2.3 FR-2600 Duct Banks ------------------------------------------------------------- 6

5.0 TECHNICAL EVALUATION

7 5.1 Potential for Cross-contamination from Subsequent Activities ----------------- 7 5.1.1 FA-0400 Fuel Building ---------------------------------------------------------- 7 5.1.2 FR-Oil 1 Yard West Excavations ----------------------------------------------- 7 5.1.3 FR-2600 Duct Banks ------------------------------------------------------------- 8 6.0 FINAL STATUS SURVEY REPORT --------------------------------------------------9 6.1 Overview of the Results -------------------------------------------------------------- 9 6.2 Discussion of Changes to FSS Program --------------------------------------------10 6.3 Final Status Survey Methodology --------------------------------------------------- 10 6.4 Final Status Survey Results ---------------------------------------------------------- 11 6.5 Survey Unit Conclusions ------------------------------------------------------------- I 1

7.0 REFERENCES

12 Figure 1 Survey Areas Figure 2 Survey Areas (Site Industrial Area)

Page 1 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 1.0 Description This letter is submitted as a supplement to Proposed Change No. 218 (Reference 7.3), which requests an amendment to the Operating License No. DPR-36 for Maine Yankee, specifically License Condition 2.B(9), addressing release of lands from the jurisdiction of the Facility Operating License. Maine Yankee requested that the NRC review and approve the release of remaining land under License No. DPR-36 with the exception of the land where the Independent Spend Fuel Storage Installation (ISFSI) is located. In support of that request, Maine Yankee supplied the information required in LTP section 1.4.2 and 5.9.3. The land area associated with the license amendment request included the entire non-ISFSI portion of the site land. Maine Yankee is submitting the required dismantlement and survey information for the survey units that make up the non-ISFSI portion of the site land in a phased fashion. Other descriptive information and technical evaluations contained in Reference No. 7.3 are unaffected by these submittals and are, therefore, not included in this submittal, as indicated.

In this submittal, Maine Yankee is providing the dismantlement and survey information for three areas (four survey units), as described in Table 1 in Section 4.1.1. Maine Yankee is providing this information to facilitate NRC review and acceptance. This written NRC acceptance must conclude, for the land associated with the release, that the remaining 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 criteria of 10 millirem TEDE per year over background (all pathways) with no more than 4 millirem (as distinguishable from background) TEDE per year from groundwater sources of drinking water in accordance with the approved License Termination Plan.

Reference 7.3 provided the information required by section 1.4 of Maine Yankee's License Termination Plan (LTP). LTP section 1.4 discusses the information to be provided in support of releasing land from the jurisdiction of License No. DPR-36 and also describes Maine Yankee's overall phased approach to releasing land. This submittal provides the dismantlement, FSS results, and recontamination prevention and control information required by LTP section 1.4 specific to the survey units covered in this submittal.

The information contained in this submittal, together with the information provided in the prior and subsequent supplemental phases will be sufficient for the NRC to make a determination equivalent to 10 CFR 50.82(a)(l 1) regarding the lands to be released from the license. Once these lands are so released, it is understood that the NRC wvill not require any additional surveys or decontamination of these areas unless the NRC determines that the criteria of 10CFR Part 20, Subpart E were not met and that residual activity remaining on the land could result in a significant threat to public health and safety.

2.0 Proposed License Condition The proposed wording for the license condition is provided in Reference 7.3 and is not affected by this supplement.

Page 2 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 3.0 Background Reference 7.3 transmitted an application to amend Maine Yankee's License No. DPR-36 to release the remaining non-ISFSI land from the jurisdiction of the license. The process for releasing land from Maine Yankee's license is established in section 1.4 of the License Termination Plan. This LTP section defines the information that will be provided to support release of land from Maine Yankee's license. This information, includes (1) a description of the boundaries associated with the area to be released, (2) discussion of dismantlement activities performed; (3) final status survey results; (4) evaluation of the potential for re-contamination and controls applied to prevent this; (5) an evaluation of the impact on the exclusion area for site lands remaining under the Part 50 license; (6) an evaluation of possible combined dose effects as a result of partial release; (7) an evaluation of potential impact on various licensee programs and; (8) a no significant hazards determination evaluation. Items (1), (5), (6), (7), and (8) are applicable to the License Amendment Request and the release of the entire remaining non-ISFSI land. Items (2), (3), and (4) are specific to each survey unit/area. This information is contained in this submittal for the survey units covered by this submittal.

4.0 Site Information and Physical Description 4.1 Physical Description of Land to be Released The land to be released is described in Reference 7.3 and is unchanged by this submittal.

4.1.1 Survey Unit Information Included in this Submittal As discussed in section 1.0 above, this submittal provides a discussion of demolition activities completed and final status survey results for the survey units located on the proposed land to be released. Details are provided for each survey unit on survey methods, results, data analysis, and conclusions. Additional information on all remaining survey units for the Non-ISFSI land areas have been provided in previous submittals or will be provided in subsequent submittals. In all cases, Maine Yankee is providing sufficient information, as required, relating to each survey unit so that the NRC staff can verify that the License Termination Plan has been fully implemented for each survey area and that the final status survey results support unrestricted release of the land from License DPR-36 in accordance with the proposed license amendment.

Table 1 provides a description of the survey units addressed in this submittal.

Page 3 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I Table 1 - Survey Unit Description Survey Survey Class General Description of Survey Unit Area Unit FA-0400 I 1 Fuel Building - The survey unit is located in the Restricted Area and consists of exposed surfaces within the Fuel Building footprint. The survey unit resulted from the demolition and removal of the Fuel Building and various adjoining support structures (RCA Building, TK-85 Pit and Pipe Tunnel.) The survey unit is approximately 1245 in2 .

FR-0 11 15 1 Yard West Excavations - The survey unit is located in the Restricted Area, north of the former Containment Building and encompasses the majority of the Primary Auxiliary Building (PAB) footprint. The survey unit consists of relatively flat terrain. The survey unit is approximately 1029.5 M2 .

FR-0 1I1 16 I Yard West Excavations - The survey unit is located in the current Restricted Area, north of the former PAB and encompassed the area of the former BWST and reserve station transformers (X14 & X16). The survey units was an area composed of soil, backfill, and various concrete pad and wall remnants. It included excavated trenches where storm drain piping was removed. The survey unit is approximately 1273 rn2 FR-2600 1 3 Duct Banks - The remaining electrical cable duct banks located within the North end of the developed site (Balance of Plant Land) and the North end of the Restricted Area. The accessible portions of the Survey Unit are the concrete manhole (MH) and handhole (HH) structures. The survey unit is approximately 5,396 m2 These areas and locations of these survey units are shown in Figure 1. The cross-hatched portions of the site represent the areas for which detailed dismantlement and survey information is being provided in this submittal. Shaded areas in Figure I represent those included in previous submittals. See Figure 2 for an expanded scale illustration, showing the site's industrial area.

Page 4 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 4.1.2 Survey Unit Information Being Provided in Subsequent Submittals As discussed above, Maine Yankee will provide an additional submittal of detailed information on dismantlement activities and final status survey results as these activities are completed. Below is a list of the Survey Areas that remain to be submitted along with an expected schedule for submittal. The schedule indicates the changes to the schedule from that provided in the last FSS Report. These survey areas encompass the remaining survey areas specified in the Maine Yankee License Termination Plan that have not yet been submitted. The actual submittal schedule, the grouping and scope of survey areas, and sequence of these survey areas, is subject to adjustment based upon the progress of dismantlement, remediation and survey activities.

Tenth Submi'ttal Sqhcbedul for 5127105 FA-0400 Fuel Buildiing - 1 Sui vey Unit (moved to Submittal 9A)

FD-0600 Service Water Piping FR-0 11 Yard West Excavations - 3 Survey Units [18, 19, 20] (15 & 16 moved to Submittal 9A)

FR-0200 Yard East - 6 Survey Units FR-2600 Duct; Bunks(moved to Submittal 9A)

FR-2900 Railroad Tracks & Roadways - 2 Survey Units 4.2 Dismantlement Activities The Maine Yankee License Termination Plan (LTP) describes the dismantlement activities to be performed for each structure and area of the Maine Yankee plant. In general, the LTP indicates that structures will be demolished to an elevation corresponding to three feet below grade. A few structures will remain in-place including the 345 kV switchyard and associated relay house.

The LTP stated the possibility of other structures, such as the Warehouses and Staff Building, to be left standing following successful completion of final status surveys. The Warehouses and Staff Building have now been demolished. The former Low Level Waste Storage Building, now the ISFSI Security Operations Building (SOB), will remain in-place until fuel is transferred to the United States Department of Energy and will be dismantled and/or released concurrent with FSS of the ISFSI and license termination. Portions of the west plant access road will remain in-place to service the ISFSI and/or other future uses of the site. Since Old Ferry Road is a public road, it will also remain in-place. Certain below grade structural remnants and buried/embedded piping will remain in-place as described in LTP section 3.2.4.

Various options for sequencing building demolition and final status survey activities are established for buildings within the Restricted Area. Typically, a final status survey is conducted on building basement surfaces before fill material is placed in the basement. The fuel building will be demolished to bedrock, except for the fuel pool slab, and surveyed as an excavation prior to backfill. Routine communications are held with State of Maine and NRC representatives to facilitate scheduling of State and NRC surveys, as necessary.

Page 5 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I This section reviews the activities that have been performed for the survey area(s) included in this submittal.

4.2.1 FA-0400 Fuel Building LTP Section 3.2.4 indicated that the Fuel Building would be demolished to 3 ft below grade. Basement foundations below this level would remain in place and be backfilled with soil fill following remediation, as required, and final status survey. All of the intervening walls and floors in the basements may be removed. The spent fuel pool liner would be removed due to known contamination levels. All demolition activities associated with the Fuel Building have been completed.

4.2.2 FR-01 11 Yard West Excavations Survey Area FR-01 11 addresses FSS in a number of soil remediation areas within the site's radiologically RA and is comprised of twenty survey units.

This report includes the FSS for two survey units from this area, Survey Units 15 and 16.

The FSS of the other survey units from FR-0 1I1 have either been reported in previous submittals, or will be reported in subsequent submittals.

Dismantlement activities for these survey units involved demolition of above grade structures including the Primary Auxiliary Building, Borated Water Storage Tank (BWST) and reserve station transformers (X14 & X16). These survey units included surface and subsurface excavations as required to remediate contaminated soils, structures and piping.

4.2.3 FR-2600 Duct Banks Cables were removed from the duct banks and the manholes were cleaned of debris. The survey was conducted on the manhole and handhole surfaces prior to backfill Page 6 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 5.0 Technical Evaluation 5.1 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 (FSS). Maine Yankee LTP sections 3.5.6, 5.1.2 and 5.1 1 describe contamination and access controls measures and periodic routine monitoring practices to prevent and/or detect the re-contamination of survey areas during or following FSS.

These requirements are implemented, as appropriate, through established procedures and were summarized in Reference 7.3.

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:

5.1.1 FA-0400 Fuel Building This survey unit is within the RA. Unlike the Containment, Spray Building, and PAB, FSS was performed after the demolition of the above grade structure and any necessary remediation. Following FSS of the survey unit, the area was backfilled and removed from the Restricted Area. Standard controls and procedures were implemented including provisions for access control, postings, and routine surveys.

5.1.2 FR-O11 Yard West Excavations Contamination controls for the soil remediation areas required special measures due to the proximity of other demolition and excavation work on-going in adjacent survey units and to manage water from both rain and groundwater sources.

1. In general, standard access controls and posting requirements were implemented following the completion of excavation.

2. Buffer zones were established around excavation areas to minimize the potential for foreign material to be inadvertently moved into the excavation.

3. As a general practice, backfilling was accomplished as expeditiously as possible, to minimize the duration that the excavation was open.

4. Due to rainwater and groundwater intrusion, a number of water management measures were instituted. Dikes were used around the open excavation to minimize rainwater accumulation within the excavation. Pooled water in the excavation was sampled, processed, and discharged, meeting applicable discharge permit requirements.

As an additional control measure, following FSS of these survey units, the site RA boundaries were revised to reduce the overall size of the RA. As a result, the subject FR-0111 survey unit areas were no longer within the RA. This action not only provides for improved management and control of activities (within a smaller RA) but also further Page 7 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I reduces the possibility of vehicles traversing and contaminating the subject FR-0 11 survey unit areas.

The conduct of FSS on FR-0111 -SU15 also acted as the post demolition verification survey of the PAB footprint (FA-0600) following removal of the sacrificial fill layer.

5.1.3 FR-2600 Duct Banks This survey unit area is both inside and outside the RA. The majority of the remaining duct banks, were located outside the RA during plant operation and were not used to transport any contaminated media. Prior to surveying manhole MH-l and handhole HH-4, it was discovered that the top and side of the manhole were damaged and the handhole had been removed. An evaluation concerning potential contamination of MH-1 as a result of the broken top/wall concluded that the manhole was not impacted by plant-derived materials and met the requirements for a Class 3 area. Following the completion of FSS, manholes and handholes were backfilled. Standard controls and procedures were then implemented.

Page 8 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 6.0 Final Status Survey Report Maine Yankee LTP section 5.9.3 identifies the contents of the written reports of final status survey results that are to be submitted to the NRC. These contents include the items described in NUREG 1757, Vol. 2, Section 4.5 (Reference 7.6). The survey unit design information and survey results are provided below in summary fashion. Specific survey unit design details and results are provided in a copy of each survey unit release record in Attachment II of this submittal.

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

1. FA-0400-SU-1 Fuel Building - The survey unit is located in the Restricted Area and consists of exposed surfaces within the Fuel Building footprint. The survey unit resulted from the demolition and removal of the Fuel Building and various adjoining support structures (RCA Building, TK-85 Pit and Pipe Tunnel.)

2. FR-0111-SU-15 Yard West Excavations - The survey unit is located in the Restricted Area, north of the former Containment Building and encompasses the majority of the Primary Auxiliary Building (PAB) footprint.

3. FR-0111-SU-16 Yard West Excavations - The survey unit is located in the current Restricted Area, north of the former PAB and encompassed the area of the former BWST and reserve station transformers (X14 &

X16).

4. FR-2600-SU-1 Duct Banks - The remaining electrical cable duct banks located within the North end of the developed site (Balance of Plant Land) and the North end of the Restricted Area.

The release record 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 and a simplified general retrospective dose estimate; 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 release records for these survey units demonstrate that they meet the criteria for release for unrestricted use in accordance with the NRC approved Maine Yankee License Termination Plan.

Page 9 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT 1 6.2 Discussion of Changes to FSS Program The purpose of this section is to discuss changes to the FSS program. Relevant NRC guidance documents (Reference Nos. 7.5 and 7.6) recommend a discussion of any changes that were made in the final status survey from what was proposed in the decommissioning plan or other prior submittals. The impacts of applicable changes on each survey unit are discussed in the survey units' release record provided in Attachment II.

There were no changes to the LTP with potential impact to the survey units in this FSS Final Report.

6.3 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 site land. Table 2 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 static measurement taken, the percent scan coverage, the Derived Concentration Guideline Limit (DCGL), the design DCGLEMC 2 , and the number of measurements required.

Table 2 - Survey Unit Final Parameters Survey Class Survey Standard LBGR DCGL Design Units No. % Scan Unit Unit Size Deviation DCGLENIC Mleas.

FA-0400 Fuel Building 1 I 1 [ 1,245 l 3,606 l 9,000 18,000 36,000 l dpm/100 cm 15 100 FR-01 11 Yard West Excavations 15 1 1,029.5 1.33 1.2 2.39 4.27 pci/g Cs-137 40 100 0.86 1.54 pCilg Cs-60 16 1 1,273 1.33 1.2 2.39 4.1 pci/g Cs-137 40 100

_ _0.86 1.5 pCilg Cs-60 FR-2600 Duct Banks I 1 3 l 5,396 308 8,876 l9,800 N/A dpm/ I00cm' 14 l 5 2 DCGLENc: Derived Concentration Guideline Limit for the Elevated Measurement Comparison Page 10 ofl3

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 6.4 Final Status Survey Results The methods used to determine the number of static measurements to be taken are described in the LTP and the specific survey unit release records provided in Attachment II.

Table 3 - Survey Unit FSS Results Survey Class No of Static Mean Maximum Standard Units No. Scan Unit Meas. Sample Sample Deviation Elevated Taken (see units) (see units) (see units) Areas

.( Note 1)

FA-0400 Fuel Building I I I 1 50 J 90 [ 1,216 179 ldpm/lOOcmMl 0 FR-0111 Yard 'WestExcavations 15 1 42 9.49E-02 2.58E-01 2.83E-02 Unitized 0 16 1 42 1.45E-01 1.27E-00 1.94E-01 Unitized 3 FR-2600 Duct Banks 1 3 l 14 1,632 2,857 803 dpm/lOOcm 2 0

. Note 1: 'I his column (No. Scan Elevated Areas) indicates the number o1 veritied scan alarms whose post investigation, as-left, contamination level exceeded the DCGL (or unity for multiple nuclides).

6.5 Survey Unit Conclusions Maine Yankee concludes that this information is sufficient for the NRC to make a determination equivalent to 10 CFR 50.82(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 10 CFR part 20, subpart E by meeting a site release criteria of 10 millirem TEDE per year over background (all pathways) with no more than 4 millirem (as distinguishable from background)

TEDE per year from groundwater sources of drinking water in accordance with the approved License Termination Plan.

Page 11 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 7.0 References 7.1 Maine Yankee Letter to USNRC dated October 15, 2002, "Revision 3, Maine Yankee's License Termination Plan", MN-02-048 7.2 USNRC Letter to Maine Yankee dated February 28, 2003, "Issuance of Amendment No.

168 to Facility Operating License No. DPR Maine Yankee Atomic Power Station (TAC No. M8000) - Approval of the MY License Termination Plan 7.3 Maine Yankee Letter to the USNRC, MN-04-020, dated March 15, 2004, License Amendment Request: Release of Non-ISFSI Site Land, Proposed Change No. 218 7.4 Maine Yankee Letter to the USNRC, MN-04-03 1, dated May 6,2004, Release of Non-ISFSI Site Land - FSS Final Report No. IA, Proposed Change No. 218, Supplement 1 7.5 USNRC, NUREG 1727 "NMSS Decommissioning Standard Review Plan" 7.6 USNRC, NUREG 1757 "Consolidated NMSS Decommissioning Guidance" 7.7 USNRC, NUREG 1575 "Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM)" Revision 1 dated October 18, 2000, supplemented June 2001 7.8 Maine Yankee Letter to the USNRC, MN-04-044, dated August 12, 2004, Release of Non-ISFSI Site Land - Resubmittal of FSS Final Report No. 1, Proposed Change No.

218, Supplement 2 7.9 Maine Yankee Letter to the USNRC, MN-04-047, dated September 2, 2004, License Amendment Request - Release of Non-ISFSI Site Lands, Proposed Change No. 218, Supplement 3 7.10 Maine Yankee Letter to the USNRC, MN-04-49, dated September 15, 2004, Release of Non-ISFSI Site Land - - FSS Final Report No. 2, Proposed Change No. 218, Supplement 4 7.11 Maine Yankee Letter to the USNRC, MN-04-052, dated October 12, 2004, Release of Non-ISFSI Site Land - FSS Final Report No. 3, Proposed Change No. 218, Supplement 5 7.12 Maine Yankee Letter to the USNRC, MN-04-053, dated October 14, 2004, Release of Non-ISFSI Site Land - Addendum to FSS Final Report No. 1, Proposed Change No. 218, Supplement 6 7.13 Maine Yankee Letter to the USNRC, MN-04-056, dated November 17, 2004, Release of Non-ISFSI Site Land - FSS Final Report No. 4, Proposed Change No. 218, Supplement 7 7.14 Maine Yankee Letter to the USNRC, MN-04-035, dated May 13, 2004, Area Classification Change: Containment Foundation Drain 7.15 Maine Yankee Letter to the USNRC, MN-02-063, dated December 12, 2002, Update on Forebay Dike Coring Results and Associated Changes to LTP Attachment 2H (LTP Revision 3 Addenda) 7.16 Maine Yankee Letter to the USNRC, MN-03-004, dated January 21, 2003, Forebay Remediation Plan Phase 2 7.17 Maine Yankee Letter to the USNRC, MN-03-049, dated September 11, 2003, Proposed Change: Revised Activated Concrete DCGL and More Realistic Activated Concrete Dose Modeling - License Condition 2.B.(10), License Termination 7.18 USNRC Letter to Maine Yankee dated February 18, 2004, Issuance of Amendment No.

170 to Facility Operating License No. DPR Maine Yankee Atomic Power Station (TAC NO. M8000) 7.19 Maine Yankee Letter to the USNRC, MN-04-059, dated December 7, 2004, Release of Non-ISFSI Site Land - FSS Final Report No. 5, Proposed Change No. 218, Supplement 9 Page 12 of 13

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT I 7.20 Maine Yankee Letter to the USNRC, MN-03-051, dated September 3, 2003, Technical Basis Document: Forebay FSS Survey Measurement Methods (In Situ Gamma Spectroscopy) - 30 Day Notice LTP Requirement 7.21 Maine Yankee Letter to the USNRC, MN-03-067, dated October 21, 2003, Maine Yankee Response to NRC and State of Maine Comments on the Technical Basis Document: Forebay FSS Survey Measurement Methods (In Situ Gamma Spectroscopy) 7.22 Maine Yankee Letter to the USNRC, MN-02-063, dated December 12, 2002, Update on Forebay Dike Coring Results and Associated Changes to LTP Attachment 2H (LTP Revision 3 Addenda) 7.23 Maine Yankee Letter to the USNRC, MN-04-060, dated December 22, 2004, Release of Non-ISFSI Site Land - FSS Final Report No. 6, Proposed Change No. 218, Supplement 10 7.24 Maine Yankee Letter to the USNRC, MN-04-061, dated December 23, 2004, Response to NRC RAIs on FSS Report No. 2, Proposed Change No. 218, Supplement 11 7.25 Maine Yankee Letter to the USNRC, MN-05-001, dated January 20, 2005, Release of Non-ISFSI Site Land - FSS Final Report No. 7, Proposed Change No. 218, Supplement 12 7.26 Maine Yankee Letter to the USNRC, MN-05-007, dated February 17, 2005, Release of Non-ISFSI Site Land - FSS Final Report No. 8, Proposed Change No. 218, Supplement 15 7.27 Maine Yankee Letter to the USNRC, MN-05-002, dated January 26, 2005, Technical Basis Document for NRC Review: Exploranium GR-130 minimum Detectable Concentration (MDC) of Cs-137 and Co-60 in Surface Soil - 30 Day Notice per LTP Requirement.

7.28 USNRC Letter to Maine Yankee dated February 24, 2005 entitled "Acceptance of Maine Yankee Technical Basis Document for the Limited Use of the Exploranium GR-130 Instrument".

7.29 Maine Yankee Letter to the USNRC, MN-05-003, dated January 26, 2005, Area Classification Change: Storm Drains (D3500) - Section 7 7.30 USNRC Letter to Maine Yankee dated February 9, 2005, "Response to Area Classification Change: Storm Drains (D3500)"

7.31 Maine Yankee Letter to the USNRC, MN-05-009, dated February 23, 2005, Response to NRC Comments on Maine Yankee Area Classification Change: Storm Drains (D3500) -

Section 7 7.32 USNRC Letter to Maine Yankee dated March 21, 2005, Storm Drain Area Survey Unit Classification Change 7.33 Maine Yankee Letter to USNRC, MN-05-016, dated April 7, 2005, Release of Non-ISFSI Site Land - FSS Final Report No. 9, Proposed Change No. 218, Supplement 18 Page 13 of 13

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R0400 Foreboy MAINE STATE GEOLOGICAL COORDINATE SYSTEM R0500 Bailey.Point R0800 Administration and Parking Areas R0900 Balance of Plant Area RIOO Foxbird Island R1300 ISFSI Area/Contractor Parking Lot R1800 Bailey House Land R2900 Roads and Rails

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Previously Submitted FA0400 - Fuel Building Structural Footprint

- Survey Unit 1 FROI 1 - Soil Reriediotion Areas E Submitted in this Report - Survey Units 15 & 16 FR2600 - Electrical Ductbonks and Manholes I Not Depicted)

- Survey Unit 1 (D

Final Status Survey Final Report No. 9A, Revision 0 ATTACHMENT 11 Final Status Survey Release Records

1. FA-0400-SU-1 Fuel Building - The survey unit is located in the Restricted Area and consists of exposed surfaces within the Fuel Building footprint. The survey unit resulted from the demolition and removal of the Fuel Building and various adjoining support structures (RCA Building, TK-85 Pit and Pipe Tunnel.)

2. FR-0111-SU-15 Yard West Excavations - The survey unit is located in the Restricted Area, north of the former Containment Building and encompasses the majority of the Primary Auxiliary Building (PAB) footprint

3. FR-0111-SU-16 Yard West Excavations - The survey unit is located in the current Restricted Area, north of the former PAB and encompassed the area of the former BWST and reserve station transformers (X14 &

X16).

4. FR-2600-SU-1 Duct Banks - The remaining electrical cable duct banks located within the North end of the developed site (Balance of Plant Land) and the North end of the Restricted Area.

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FA-0400 FUEL BUILDING SURVEY UNIT 1 Prepared By: I_ Date: /5 IL FSS Engineer - Signature G;. ,nis2 A Printed Name Reviewed By: Date:/5 /d 5 Railist -Signature LCNY 'r y 2ck s Printed Name Reviewed By: 4- Date:.!! t! g dent Review - Signature Approved By: Agee Date: S5o

-'s en nt end Signature Printed Name Approved By: _z Date: t/@7/o .

A1-SS, MOP - Signature wR . e Kz Printed Name Revision 0

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FA-0400 FUEL BUILDING SURVEY UNIT 1 A. SURVEY UNIT DESCRIPTION Survey Unit 1 is located in Survey Area FA-0400, the Fuel Building. The survey unit consists of exposed surfaces within the Fuel Building footprint. The survey unit is composed primarily of exposed concrete foundation remnants and exposed rock ledge. There were areas consisting of soil located around the periphery of the survey unit. It was created in part as a result of the demolition and removal of the Fuel Building and various adjoining support structures (RCA Building, TK-85 Pit, and Pipe Tunnel). Also contributing to the size and depth of this area was the excavation of contaminated material found between the Fuel Building exterior and the outer Reactor Containment Building wall (shake space). The southwest comer of the survey unit is located near grid coordinates 407,628 N and 623,742 E using the Maine State Coordinate System (West Zone) NAD 1927.

The Fuel Building is shown in relation to other major site structures in map FA0400Ul-SITE.

The survey unit topography is shown on map FA0400UI-INFO. All maps referenced in this release record are provided in Attachment 1 unless otherwise noted. The survey unit is approximately 1,245 m2 .

B. SURVEY UNIT DESIGN INFORMATION The area was designated a Class I structure survey unit per the LTP (Table 5-4A, A0400, Fuel Building). Significant remediation was performed in the excavated area prior to FSS.

Since the survey unit was already Class 1, no reassessment of classification was required.

The survey unit design parameters are shown in Table 1. Given a relative shift of 2.4, it was determined that 15 direct measurements were required for the Sign Test; however, the number of samples was increased to .50 to increase the area factor and to meet the minimum sample density of 1/50 n2 . Measurement locations were determined using a fixed grid with a randomly determined start point and are illustrated on the map FA0400U1-DIRT. Because of the poor surface condition of the remaining concrete and rock ledge, volumetric samples were collected. Similarly, volumetric samples were collected in areas containing soil. In all cases, the results from the sample analysis were converted to surface activity as shown in Table 2. Direct measurements were analyzed with laboratory gamma spectroscopy instrumentation.

In accordance with the LTP, a total of 193 scans covering 100% of the 1,245 m 2 area were required for the Class I survey unit. This was accomplished by use of an in situ gamma spectroscopy detector (ISOCS) configured at a 2-meter distance, to obtain overlapping 12.6-M2 fields of view. The ISOCS detector was positioned perpendicular to the surface.

ISOCS survey scan locations are shown on illustrations FA0400UI-SCAN and FA0400UI-NONVERTSCAN.

FA-0400-01, Revision 0 Page 2 of 25

The ISOCS scan investigation setpoint was conservatively set at the DCGL, as shown in Table 2-2 (Attachment 2). The instruments used in this survey are listed by model and serial number in Attachment 2 (Table 2-1). Scan MDCs are also listed in Attachment 2 (Table 2-2) and are compared to the DCGL, the investigation level, and the DCGLEMC. As shown in this table, the scan MDC is less than the scan investigation level in all cases, thus providing high confidence (95% or higher) that an elevated area would be detected in the scanning process.

Further, since the investigation level at the alarm setpoint was always less than the design DCGLEmc, no EMC sample size adjustment was necessary.

TABLE 1 SURVEY UNIT DESIGN PARAMETERS Survey Unit Design Criteria Basis Area 1,245 m' Class 1 Basement Structure <2,000 m' Based on an LBGR of 9,000 dpm/

Number of Direct 15 (50 used) 100cm 2, sigma' of 3,606 dpmlO00 cm 2 Measurements Required 2 and a relative shift of 2.4.

Type I = Type II = 0.05 Sample Area 24.9 m 1,245 m2 / 50 samples2 Sample Grid Spacing 4.9 m (24.9)"

Scan Grid Area ISOCS scans at 2m See Section B Area Factor 2.0 50 m2 /24.9 m2 (Reference 1)

Scan Survey Area 1,245 m2 Class 1 -100%

Scan Investigation Level Gross Beta DCGL (Co-60 See Table 2-2 (Attachment 2) plus Cs-137) _

DCGL 18,000 dpm/1O00 cm' LTP, Rev. 4 (Reference 1)

Design DCGLEMc 36,000 dpm/l 00 cm2 Area Factor x DCGL Design sigma is based on characterization data, listed in LTP Table 5-IA, Fuel Building, A0400, (LTP, Rev. 4).

2 This survey unit was initially designed for N=15 samples but was increased to N=50 to increase the design area factor and to meet the minimun sample density of 1/50 O2 . The Area Factor used reflects the design grid size.

FA-0400-01, Revision 0 Page 3 of25

C. SURVEY RESULTS Fifty direct samples were obtained in Survey Unit 1. The DCGL used was the surface DCGL and direct samples were converted to surface activity. All direct measurements were less than the DCGL. The resulting data are presented in Table 2.

ISOCS gamma scans were performed at 193 locations using an investigation level of 1.80E+06 dpm/m2 (Co-60 plus Cs-137) for the 12.6 m2 field of view designed to achieve overlapping scan coverage to ensure 100 percent coverage for the survey unit. The scans were designed to achieve a Minimum Detectable Activity of 14% of the surface DCGL or better; in fact, all scans achieved 8% or better. All scan activity values were below the investigation level. An evaluation was performed to determine the attenuation effects on locations identified as having water in the field of view. The evaluation concluded that a maximum water level of 4" did not cause the MDAs or reported activity values to exceed the prescribed investigation level.

After initial review of the scan data, spotty Co-60 and Cs-137 contamination was noted at several scan locations. Based on professional judgment, package XA0400 was generated to investigate elevated Co-60 scan locations S038, S040, S045, and S081, and elevated Cs-137 scan location S136. Refer to Section D for further discussion of the investigation performed.

FA-0400-01, Revision 0 Page4of25

TABLE 2 DIRECT MEASUREMENTS Sample Location Co-60 Activity Cs-137 Activity Gross Surface Activity (Note_2) pCi/g pCilg dpmn100 cm2 (Note 3)

FA0400-01-lSOOI-VS-DIRT < 8.98E-02 < 7.53E-02 25 FA0400-01-IS002-VS-DIRT 1.22E-01 < 9.54E-02 42 A0400-01-lS003-VS-DIRT < 9.42E-02 < 7.19E-02 33 FA0400-01-1S004-VS-DIRT < 1.04E-01 < 9.94E-02 40 FA0400-01-lS005-VS-DIRT < IA6E-01 3.24E-01 107 FA0400-0 I-IS006-VS-DIRT < 9.07E-02 < 7.54E-02 40

-A0400-01-1S007-VS-DIRT < 1.25E-01 < 1.03E-0O 50 FA0400-01-1S008-VS-DIRT < 1.04E-01 < 8.79E-02 43 FA0400-01-lS009-VS-DIRT < 1.28E-01 < 1.09E-01 51 FA0400-01-lSO10-VS-DIRT < I.lOE-O1 < 8.1SE-02 44 FA0400-01-lSOI I-VS-DIRT < 9.60E.02 < 8.75E-02 44 FA0400-01-1S012-SS-DIRT < 3.88E-02 < 3.93E-02 36 FA0400-01-lS013-VS-DIRT < 1.30E-01 < 1.34E-01 55 FA0400-01-lS014-SS-DIRT < 5.96E-02 < 5.50E-02 49 FAO400-01-ISO15-SS-DIRT 1.45E+00 1.29E+00 1,216 FA0400-0I-lS016-VS-DIRT < 1.17E-01 < 8.46E-02 36

A0400-0I-1S01 7-VS-DIRT < 9.50E-02 < 8.92E-02 33 FA0400-01-lS018-VS-DIRT < 1.48E-O1 < 1.13E-01 47 FA0400-01-lS019-VS-DIRT < 1.06E-01 < 8.12E-02 51 A0400-0-1-S020-SS-DIRT < 5.39E-02 < 5.28E-02 42 FA0400-0-1-S021-VS-DIRT < 1.03E-01 < 1.02E-01 40

'A0400-01-1S022-VS-DIRT < 1.12E-01 < 1.06E-01 42 FA0400-01-1S023-VS-DIRT < 1.26E-01 < 1.26E-01 43 FA0400-01-1S024-SS-DIRT < 4.80E-02 < 4.89E-02 46 FA0400-0I-1S025-SS-DIRT < 7.1 1E-02 2.36E-01 131 FA0400-01-lS026-VS-DIRT < L.OOE-01 < 8.21E-02 41 A0400-01-IS027-VS-DIRT < 9.86E-02 < 1.17E-01 40 FA0400-01-lS028-VS-DIRT < 1.02E-01 < 9.61E-02 38 A0400-01-lS029-VS-DIRT < 1.06E-01 < 8.97E-02 49

A0400-01-lS030-SS-DIRT < 6.19E-02 1.08E+OO 501

'A0400-01-lS031-VS-DIRT 2.21E-01 4.66E-01 121 A0400-01-lS032-VS-DIRT < 1.27E-01 7.95E-01 174 A0400-01-lS033-VS-DIRT < 1.08E-01 < 1.08E-01 49 0AO400-01-IS034-VS-DIRT < I.OOE-01 < 8.56E-02 42 A0400-O1-1S035-SS-DIRT < 5.70E-02 5.25E-01 262 FA0400-01-1S036-VS-DIRT _ 3.59E-01 2.87E-01 106

-A0400-01-lS037-VS-DIRT < 1.38E-01 4.87E-01 III

-A0400-01-lS038-VS-DIRT < 9.54E-02 < 8.92E-02 47

A0400-01-lS039-SS-DIRT < 4.271E-02 < 3.76E-02 38

-A0400-01-lS040-SS-DIRT < .4.94E-02 < 4.62E-02 38

A0400-01-lS041-VS-DIRT < 1.31 E-01 < 1.12E-01 50

A0400-01-lS042-VS-DIRT < 1.25E-01 < 1.16E-01 54 FA-0400-01, Revision 0 Page 5 of 25

Sample Location Co-60 Activity Cs-137 Activity Gross Surface Activity (Note 2) pCifg pCig dpm100 cm2 (Note 3)

FA0400-01-1S043-VS-DMRT < 1.31E-01 <O 1.21E-01 43 FA0400-0I-1S044-SS-DIRT < 4.1OE-02 < 4.51E-02 40 FAO400-01-1S045-SS-DIRT < 5.30E-02 < 4.81E-02 38 FAO400-01-1S046-VS-DIRT < 1.23E-01 < 1.06E-01 48 FA0400-OlS047-VS-DIRT < 1.36E-01 < 1.26E-01 52 A0400-01-1S048-VS-DIRT < 1.18E-01 < 127E-01 38 A0400-01-IS049-SS-DIRT < 3.85E-02 < 3.80E-02 38 FAO400-01-1S050.VS.DIRT < 1.21E-01 < 1.14E-01 38 Mean _ 133E-01 = .82E-01 90 Median 1.OSE0OI 1.OIE-01 44 Standard Deviation 1.97E-01 2.52E-01 179 Sample Range 3.85E-02 to 1.45E+00 3.76E-02 to 1.29E+00 25 to 1,216 NOTES

1. "<" indicates MDA value. Bold indicates positive detection value.

2. VS indicates concrete or rock ledge sample. SS indicates soil sample.

3. Gross surface activity calculated using the following formula:

dpm /100cm2 pCi I g

sample itI sample area* 100cm2 /I00cm2 *222dpm/pCi where:

pCi/g=Co-60 plus Cs-137 activity sample wt sample weight in grams samnple area=523 cm 2 for 9" by 9" concrete sample, 929 cm2 for a 12" by 12" soil sample D. SURVEY UNIT INVESTIGATIONS PERFORMED AND RESULTS During FSS scans of Survey Unit 1, no scan measurements indicated activity above the survey design investigation level of 1,800,000 dpm/m2 (18,000 dpm/I 00 cm2 ).

Initial review of the ISOCS scan data revealed spotty Co-60 and Cs-137 contamination at several scan locations. Based on professional judgment, package XA0400 was generated to investigate elevated Co-60 scan locations S038, S040, S045, and S081, and elevated Cs-137 scan location S136. To investigate the elevated scan locations, SSPA-3 scans were used to isolate pockets of elevated areas within the original ISOCS scan field of view. The elevated areas were sampled and additional SSPA-3 and ISOCS measurements were made to document the as-left condition.

For the elevated Co-60 scan locations, a small elevated pocket was found in the overlapping scan grids of S040 and S045. Once the elevated pocket was remediated, subsequent as left ISOCS scans of locations S038, S040, and S045 all indicated Co-60 less than 1.00 E+05 dpm/m 2 . No elevated areas were found during the E1600/SSPA-3 scans of scan grid S038.

Location S081 contained spot contamination. Three small pockets were discovered and removed and an as-left rescan of location S081 indicated Co-60 activity of 64,027 dpm/m2 .

FA-0400-01, Revision 0 Page 6 of 25

Condition Report CR 05-023 was written to address residual activity that a surveyor employed by the State of Maine found in the survey unit for scan grid location S136. As a result of the questions raised in the Condition Report and the level of activity in the original FSS scan, the area was investigated. Based on an evaluation of the investigation results (Reference 3), it was concluded that the source term had no impact on the conclusion that the survey unit meets the release criteria. Nonetheless, the area was subsequently remediated.

The investigation results are discussed below.

Initial FSS scan grid location S136 indicated elevated Cs-137 activity of 564,370 dpm/m 2 ,

which is less than the DCGL of 1,800,000 dpmlm 2 , and corresponds to a concrete volumetric activity of 2.31 pCi/g. However, when this activity is applied to the estimated contaminated area of 0.74 m2 , the equivalent beta activity is 110,449 dpm/100 cm 2 , which exceeds the DCGL. An investigation survey was performed and, based on the results, the DCGLEMC unity fraction was determined to be 0.091, much less than unity. The subsequent remediation of the elevated area was followed by a survey resulting in an as-left ISOCS scan result of 116,100 dpm/m2 or 1,161 dpm 100 cm2 . For comparison, the initial survey unit ISOCS scan mean was 108,476 dpm/m2 which compares favorably with the as-left scan for location S1 36.

Based on volumetric sampling, the final result after remediation is 6,643 dpm/100 cm 2 which is approximately 37% of the DCGL.

The as-left survey measurements were all less than the DCGL. The arrangement for the final measurements is shown on map XA0400-UI-SCAN. The original FSS and final measurement results are shown in Table 3-i (Attachment 3).

E. SURVEY UNIT DATA ASSESSMENT An analysis of the direct sample measurement results, including the mean, median, standard deviation, and sample result range, are provided in Table 2. Positively detected values are bolded in the table. Of the 50 direct samples obtained, four samples positively identified Co-60 and nine positively identified Cs-137. All other values were below the MDA.

Identified sample activities or Minimum Detectable Activities are listed in Table 2. The mean and median activities were less than the DCGL. The average of the direct sample results was 90 dpm/nl00 cm 2 , indicating that the samples averaged 0.5% of the DCGL limit.

All direct measurement results were below the equivalent gross surface DCGL. The maximum direct sample result was equivalent to 1,216 dpmilOO cm 2 . No investigations were required based on the direct sample results since all measurement results were less than the equivalent gross surface DCGL. Five of the scan locations (S038, S040, S045, S081, and S136) were investigated due to spotty Co-60 or Cs-137 activity, but none exceeded the investigation level of 18,000 dpm/l00 cm2 .

For illustrative purposes, as indicated in LTP Section 5.9.3, a simplified dose estimate can be calculated from the mean residual contamination level of 90 dprn/l 00 cm2 . This is equivalent to an annual dose of 0.002 mrem 3 .

3.

This annual dose equivalent is based on LTP Table 6.1 lb which shows the Total Annual Dose from Contaminated Concrete to be 3.OIE-01 mrem/y. Therefore, the annual dose rate would equate to Annual Dose Me = 3.01E -1 x =.02 mremly FA-0400-01, Revision 0 Page 7 of 25

F. ADDITIONAL DATA EVALUATION Attachment 4 provides additional data evaluation associated with Survey Unit 1, including relevant statistical information. Based on survey unit direct measurement data, this attachment provides the Sign Test Summary, Quantile Plot, Histogram, and Retrospective Power Curve.

1. The Sign Test Summary provides an overall summary of design input (Table 1) and resulting calculated values used to determine the adjusted required number (N) of direct samples (per LTP Section 5.4.2). The Sign Test Summary is a separate statistical analysis that also calculates the mean, median, and standard deviation of the direct samples.

The critical value and the result of the Sign Test are provided in the Sign Test Summary table, as well as a listing of the key release criteria. As is shown in the table, all of the key release criteria were clearly satisfied for the FSS of this survey unit.

2. The Quantile Plot was generated from direct sample data listed in Table 2 and indicates general symmetry about the median. The data set and plot are consistent with expectations for a Class I survey unit. There is no reason to conclude that the data set represents other than random variations in a Class I concrete surface survey unit. It also should be noted that the maximum activity (1,216 dpm/10O cm2 at location SO15) is well below the DCGL of I8,000 dpm/l 00 cm2 .

3. A Histogram Plot was also developed based on the direct measurement values. This plot shows that the direct data were essentially a normal distribution with two outliers.

4. A Retrospective Power Curve was constructed, based on FSS results. The curve shows that this survey unit having a mean residual activity at a small fraction of the DCGL, has a high probability ("power") of meeting the release criteria. Thus, it can be concluded that the direct sample data support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and that the data quality objectives were met.

G. CHANGES IN INITIAL SURVEY UNIT ASSUMPTIONS ON EXTENT OF RESIDUAL ACTIVITY The survey was designed as a Class 1 structure survey area; the FSS results were consistent with that classification. The direct measurement sample standard deviation was less than the design sigma. Thus, a sufficient number of sample measurements were taken.

H. LTP CHANGES SUBSEQUENT TO SURVEY UNIT FSS The FSS of Survey Unit I was designed, performed, and evaluated in the March 2005-April 2005 time frame using the criteria of the LTP Revision 4 (Reference 1). No subsequent LTP changes with potential impact to this survey unit need to be evaluated.

FA-0400-01, Revision 0 Page 8 of 25

I. CONCLUSION The FSS of this survey unit was designed based on the LTP designation as a Class I area.

The survey design parameters are presented in Table 1. The required number of direct measurements was determined for the Sign Test in accordance with the LTP. As presented in Table 2, all direct samples were less than the DCGL of 18,000 dprnlO00 cm 2 .

A Sign Test Summary analysis demonstrated that the Sign Test criteria were satisfied. The direct measurement sigma was determined to be less than that used for design, thus indicating that a sufficient number of samples was taken.

The Retrospective Power Curve shown in Attachment 4 confirmed that sufficient samples were taken to support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and the data quality objectives were met. Attachment 4 also revealed that direct measurement data represented essentially a normal distribution with two outliers.

The scan survey design for this survey unit was developed in accordance with the LTP Revision 4 (Reference 1) with significant aspects of the design discussed in Section B and Table 1. JSOCS scans performed at a distance of 2 meters in a systematic grid pattern throughout the survey unit revealed no locations exceeding the investigation level of 18,000 dpm/1 00 cm 2 ; however, based on professional judgment an investigation package was generated for a total of five locations which revealed spotty Co-60 or Cs-137 contamination (refer to Section D for discussion of results).

It is concluded that FA-0400 Survey Unit 1 meets the release criteria of 10CFR20.1402 and the State of Maine enhanced criteria.

J. REFERENCES

1. Maine Yankee License Termination Plan, Revision 4, February 28, 2005 provided by Maine letter to the NRC, MN-05-010

2. Maine Yankee Calculation No. EC-003-04, Use of Canberra In Situ Object Counting System (ISOCS) for FSS Surveys

3. Memorandum, Evaluation of Potential Residual Contamination of FA0400 Survey Unit I TK-85 Pit (CR 05-023), dated April 20,2005 FA-0400-01, Revision 0 Page 9 of 25

Attachment 1 Survey Unit Maps FA-0400-01, Revision 0 Page IOof25

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Attachment 2 Survey Unit Instrumentation FA-0400-01, Revision 0 Page 17 of 25

TABLE 2-1 INSTRUMENT INFORMATION HPGe Detectors (Laboratory Analysis)

Detector No. MDC DET2 0.07 to 0.14 (pCi/g)

DET3 0.08 to 0.17 (pCi/g)

FSS1 0.05 to 0.07 (pCilg)

FSS2 0.04 to 0.06 (pCilg)

ISOCS Detectors (Field Measurements)

Detector No. MDC 7605 419 to 1,120 dpm/lOO cm' 7607 210 to 1,480 dpm/100 cm'n 7780 100 to 1,300 dpm/lOO cmi TABLE 2-2 INSTRUMENT SCAN MDC, DCGL, INVESTIGATION LEVEL, AND DCGLEMC Parameter Instrument: ISOCS Comments 227 to 1,480 dpm/1 00 cm22 Cs- 137 Design MDC specified to be Scan MDC 210 to 1,050 dprnJ100 cm Co-60 2,500 dpm/l 00 cm2

____ ___Co-60 ____ ____ plus Cs-137 Gross Surface dpm/100 cm DCGL 18,000 dpm/100 cm2 for Basement Contaminated (dpm/100 cm2 ) (Co-60 plus Cs-137) Concrete LIT Rev 4

_ Table 6.1 la (Reference 1)

Investigation Level 18,000 dpmllOO cm 2 100% DCGL (Reference 1)

(ISOCS 2m) (Co-60 plus Cs-137) 36,000 dpm/lOO cm2 AF*DCGL for Class 1 Design DCGLrmc (Co-60 plus Cs-I 37) survey unit, per LIT Section

_ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5 .6.3 FA-0400-01, Revision 0 Page 18 of 25

Attachment 3 Investigation Table FA-0400-01, Revision 0 Page 19 of 25

TABLE 3-1 INVESTIGATION TABLE INITIAL SURVEY INVESTIGATION POST-REMEDIATION SURVEY ISC en SSPA-3 Concrete TtletPost Concrete Total Beta Sample uclie p Sc)l Sample Total cmt Remediation Sample dpmJIOO Area DCGLymc Location Nucld pml Hilhes RespC dpg)0c ISOCS Scan @ Results cm 2 Factor Unity (dp/m) ale p~i9) (Nte1) 2m (dpm/m2) (pCIvg) (Note 2)

S038 Cc-c0 119610 '30 N/A N/A 70,974 N/A N/A NIA <DCGL S040 CsU7 119,750 143 NIA N/A <93, 100 N/A N/A N/A <DCGL

___ _ _ Cs-137 <1 I43 N A NI 65,151 _ _ _ _ _ _ _ _ _ _

S045 Co-60 107,160 143 N/A N/A <104,000 N/A N/A N/A <DCGL Cs-137 <115,000 1430N/A0N/

S081 Cs-137 27,900 52.4 N/A N/A 274,570 N/A N/A N/A <DCGL S136 Co.160 584,300 26.5 2.89 7,899 74,019 <0.07 6,643 N/A <DCGL Cs-137 564,370 _____ 41.4 _______ 116,100 3.23 Beta dpm,/100 Unitized cff Mean Mean

_ _ 90 .005 0.005 EMC Unity Sum 0.005 NOTES:

I

1. Total Beta dpmIlOO cm2 equals direct concrete sample (Co60 pCi/g+ Cs-137 pCi/g)*2.22 dpmfpCi*sample weight (g)lsample area (cm 2)Y(100cm2/100 cm 2).

Sample weight was 417.6 g and the sample area was 522.6 cm2 (9" by 9").

2. Total Beta dpm/100 cm 2 equals direct concrete sample (Co-60 pCVg+ Cs-137 pCig)"2.22 dpm/pCi*sample weight (g)/sample area (cm 2 )*(G00 cm 2 /100 cm 2 ).

Sample weight was 1873 g and the sample area was 206.5 cm2 (8" by 4").

II I

FA-0400-01, Revision 0 iI Page 20 of 25

Attachment 4 Statistical Data FA-0400-01, Revision 0 Page 21 of 25

Survey Package FA0400 Unit I Surface Sign Test Summary Survey Package: FA0400 Fuel Building Survey Unit: 01 Evaluator G. Madison DCGL_ : 18,000 dpm/100cm2 DCGL,.: 36,000 dpm/100cm2 LBGR: 9.000 dpm/100cm2 Sigma: 3,606 dpm/100cm2 Type I error 0.05 Type II error: 0.05 Total Instrument Efficiency: 100.0% data adjusted for various effs.

Detector Area (cm2): 100 Choosing 'NIA' sets material Material Type: NIA background to "0" Zoo::645 1.645 Sign p: 0.97725 Calculated Relative Shift: 2 _

Relative Shift Used: 2.4 Uses 3.0 If Relative Shift >3 N-Value: 12 N-Value+20%: 15 Number of Samples: 50 Median: 44 dpml100cm2 Mean: 90 dpmrl1Ocm2 Net Static Data Standard Deviation: 179 dpml100cm2 Total Standard Deviation: 179 SRSS Maximum: 1,216 dpmll00cm2 Adjusted N Value: 50 S+ Value: 50 Critical Value: 31

'S,~.iZi~S Sufficient samples collected: Pass Maximum value <DCGL,: Pass Median value <DCGLw: Pass Mean value <DCGL: Pass Maximum value <DCGL,,: Pass Total Standard Deviation <=Sigma: Pass SU passes Sign test results: Pass The survey unit passes all conditions: Pass SU Passes FA0400-SU11SurfaceSlgn 4114d05 8:56 AM a- g-O, 2 0sof Page 22 of 25

FA0400 SU-1 Quantile PLot 1400 1200 1000 Activity (dpm/1 00 I" :

Z-

.5 800 cm2) ii w-"

6 CD A: 600 - Median (dpm/1 00 ;

0. 400 cm2) i!

200 0

0 25 50 75 100 Percent I I____ ___ _I__

One-Sample T-Test Report Page/Date/Time 2 4/14/05 3:17:51 PM Database Variable C2 Plots Section Histogram of FA-0400, SU-1 E.

9!

E E

Activity (dpm100 cm2)

FA-0400-0 1, Revision 0 Page 24 of25

One-Sample T-Test Power Analysis Page/Date/Time 2 4/14/05 3:19:21 PM Chart Section Retrospective Power Curve 1 .0-p . . a I

0.84- .I a) 0.6-0 a-0.44-0.24- ;- ,

0.0 I 0 5000 iooo 15600 200 Survey Unit Mean (dpm/100 cm2)

FA-0400-01, Revision 0 Page 25 of25

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-O111 YARD WEST EXCAVATIONS SURVEY UNIT 15 Prepared By: 49d Date: 9-2C -O.S FSS Engineer-Printed Name ReviewedBy i Date: 4.05 Ftecilst - Signature Let.y Io'A.

Printed Name Reviewed By: Date: 3 A .a Indepiardellt Review - Si mture C. J. C/- SAW, Approved By. Date: 4:3/5 ntend S Signature Printed Namne Approved By. Date: M

'Sm P - Signatue Printed Name Revision 0

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-0111 YARD WEST EXCAVATIONS SURVEY UNIT 15 A. SURVEY UNIT DESCRIPTION FR-0 11 Yard West Excavations Survey Unit 15 was located north of the former Containment Building and encompasses the majority of the PAB footprint. The 1,029.5 m2 area was bordered on the West by FA-0400 Survey Unit 1, (the Spent Fuel Building Footprint). The survey unit was centered near coordinates 407,700 N and 623,900 E using Maine State Coordinate System (West Zone) NAD 1927. The location of the survey unit in relation to the Containment Building and the surrounding FR-0 11I survey units is shown on map FRO 1I lUl5-SlTE (Attachment 1). The survey unit consisted ofrelatively flat terrain as indicated on map FROl 1IUI 5-INFO. It should be noted that the Release Record for FR-0111-14 had anticipated that follow up surveys for a small strip of area adjacent to the Containment wall would be included in FR-01 11-15. Survey Unit 15 had to be reconfigured to provide for an access road which resulted in the small area adjacent to the Containment wall being placed in FR-0111 Survey Unit 19.

B. SURVEY UNIT DESIGN INFORMATION Survey Unit 15 met the LTP Revision 4 definition for a Class 1 survey unit. The survey unit design parameters are shown in Table 1. Given a relative shift of 0.8, it was determined that 40 direct measurements were required for the Sign Test. Because the measurement locations were based on a systematic square grid with a random start point, the N=40 design led to a survey unit map with 42 locations which are illustrated on map FROI I lU15-DIRT (Attachment 1). Direct measurements (soil samples) were collected from required locations and analyzed with laboratory gamma spectroscopy instrumentation.

In accordance with the LTP, scans covering 100% of the 1,029.5 rn2 area were required for the Class 1 survey unit. This was accomplished by use ofan in situ gamma spectroscopy detector (ISOCS) configured at a 3-meter distance from the surface to obtain overlapping 28-m 2 fields of view. Two ISOCS measurements (SO58 and S059) were configured with the detector located 2 meters from the concrete surfaces in the area of the former pipe tunnel.

The ISOCS detector was positioned perpendicular to the surface, as appropriate, to provide 100% scan coverage of the surface. Locations and orientation (vertical or horizontal) of the 59 survey scans are shown on map FROl 1IUI5-SCAN.

The ISOCS scans were configured to ensure 100% scan coverage of all exposed surfaces within Survey Unit 15. The survey instriments used are listed by model and serial number in Attachment 2 (Table 2-1). Scan MDCs are also listed in Attachment 2 (Table 2-2) and are compared to the DCGL, the investigation level, and the DCGLEmc. The scan MDC is less than the scan investigation level, thus providing high confidence (95% or higher) that an elevated area would be detected in the scanning process. Further, since the investigation level was always less than the design DCGLEMC, no EMC sample size adjustment was necessary.

FR-O111-15,RevisionO Page 2 of 20

TABLE I SURVEY UNIT DESIGN PARAMETERS Survey Unit Design Criteria Basi Area 1,029.5 m2 Class 1<2,000 O m2 Based on an LBGR of 1.2 pCi/g, Number of Direct sigma t of 1.33 pCi/g, and a relative Measurements Required 40 shift of 0.8.

Type I = Type 0.05 Sample Area 26.0 m2 1,029.5 m'/40 - 26.0 mn' Sample Grid Spacing 5.0 m (26.0)'=

Scan Gid Area ISOCS scan at 2 and3 See Section B Scan___Grid ___Area__ meters Area Factor 1.8 Class I Area, LTP Table 6-12 Scan Area 1,029.5 Class I Area -100%

1.0 pCilg Cs-137 ISOCS investigation levels with Scan Investigation Level 036 pCi/gdetector at 2 and 3-me heigt 0.36 ~i/g o-60(Reference 3)

DCGL 2.39 pCilg Cs-137 Reference 1

____ ____ ___ 0.86 pCi/g Co-60 Design DCGLEmc 4.27 pCilg Cs-137 DCGL x Area Factor for Class I Design_________1.54 pCi/g Co-60 survey unit, per LTP Section 5.6.3 C. SURVEY RESULTS A total of 42 direct measurements were performed in Survey Unit 15. Five samples contained Cs-1 37 with levels of residual activity below the DCGL. Additionally, one sample contained Co-60 below the DCGL. All other measurements were below the MDA. The results are presented in Table 2.

ISOCS gamma scans were performed at 59 locations using an investigation level of 1.0 pCilg Cs-137 and 0.36 pCi/g Co-60. Two ofthe locations scanned consisted primarilyofconcrete media, the balance were soil scan measurements. Media appropriate geometries were applied to each ISOCS measurement. The gamma scans were performed for a sufficient count time to achieve a Minimum Detectable Activity (MDA) of approximately 30% ofthe DCGL. All identified scan activity levels and MDAs were below the investigation levels. Therefore, no investigation surveys were performed as a result of the scan surveys.

LTP Revision 4, Table 5-lC for RCA Yard West, RODO FR-11 1-IS, Revision 0 Page 3 of 20

TABLE 2 DIRECr ASUREMENTS Cs-137 Ulcertainty Co-60 Uncertainty Unitized Value Sample Number (pCUgL) (pCL/g) of Unity Rule FRO1lI15ISOOI < 5.81E-02 < 5.83E-02 9.21E02 FROIIIISISO02 < S.02E-02 < 4.72E-02 7.S9E-02 FROlll151S003 < 5.SIE-02 , < 5.68E-02 8.91E-02 FROIIlISIS004 < 6.59E-02 1.98E-1 3.44E-02 2M58E-O1 FROllllSlSOOS < 5.27E-02 < 5.IOE-02 8.14E-02 FRO11115ISO06 < 6.09E-02 < 6.16E-02 9.71E-02 FROI11 151S007 < 4.52E-02 e 5.16E-02 7.89E-02 FRO111151S08 S< 5.S9E-02 < 6.04E-02 9.36E-02 FROlIlSIS009 7.19E-02 2.94E-02 < 6.00E.02 9.99E-02 FROIIIISISOIO < 5.92E-02 < 5.95E-02 9.40E-02 FROIIIISlOI < 4.99E-02 < 5.S9E-02 8.59E-02 FROlllIS01SO2 < 5.59E-02 < S.61E-02 8.86E-02 FROIII1SlSO13 < 4.44E-02 < 4.57E-02 7.17E-02 FROllSISSO14 < 5.73E-02 < 5.73E-02 9.06E-02 FROIII1ISSO15 < 5.18E-02 < 4.94E-02 7.91E-02 FROIII15IS1S6 < 5.81E-02 < 5.98E-02 9.38E-02 FROllllSISO17 < S.35E-02 < 5.70E-02 8.87E-02 FROIIIISISOI < 5.801E-02 < 5.98E.02 9.38E-02 FROIlIlSISO19 < 6.27E-02 < 5.94E.02 9.53E-02 FROIII151S020 < 6SE-02 < 5.89E-02 9.59E-02 FROl11lSISO21 < 58E-02 < 4.83E-02 7.95E-02 FROIIIlSISO22 < SAOE-02 < 6.26E-02 9.54E.02 FROIIIISISO23 < 5.52E-02 < 5.88E-02 9.1SE-02 FROIIIISlS024 < S.ISE-02 _ < 5.99E-02 9.12E-02 FROIII1SISO25 < 4.53E-02 < 5.30E-02 8.06E-02 FRO111151S026 < 5.OOE-02 < 5.95E-02 9.01E-02 FROIII151S027 <- 4.76E-02 < 5.14E-02 7.97E-02 FROIII151S028 < S.91E-02 < 5.94E-02 _ 9.38E-02 FROIII151S029 < 5.73E-02 < 5.82E-02 9.16E-02 FROl11151S030 < 5.09E-02 < 535E-02 8.35E-02 FRO11151SO31 < 5.64E102 < 6.44E-02 9.8SE-02 FROIII151S032 < S.83E-02 < 5.46E-02 8.79E-02 FROll lSlS033 6.71E-02 2.82E-02 < 6.49E-02 1.04E-O1 FR01111SIS034 1.46E-01 3-36E.02 < 5.98E-02 _ I3OE-O1 FROII11SlSO35 < 5.66E-02 < 5.IIE-02 8.31E-02 FR011I151S036 < 4.9SE-02 < 4.76E-02 7.61E-02 FROIISISO37 < 5.19E-02 < S.71E-02 8.81E-02 FRDIIIISIS038 &90E-02 2.83E.02 c S.OSE-02 9.63E-02 FROIIIISIS039 126E-O1 3.78E-02 < 6.60E-02 1.29E-01 FRO111151SO40 < 6.61E-02 < C6.55E-02 1.04E-Ol FR0111151S041 < 5.93E-02 < 5.ASE-02 _ .SOE-02 FROIlI15lSO42 < 5.09E-02 < 5.25E-02 8.23E-02 Mean 604E-O2 S.99E;02 9.49E-02 Median 5.62E-02 ' 578E-02 9.09E-02 Standard Deviation 1.89E-02 2.2ME-02 2.83E-02 ange44E02o 4.57E-02to 7.17E-W2 to

___ _ 1.46E-01' 1.9_E_01_ 258E-OI

"<9 indicates MDA value. Bold i icates positive detection vaue.

FR-OIl1-15, Revision 0 Page 4 of20

D. SURVEY UNIT INVESTIGATIONS PERFORMED AND RESULTS Based on the scan results, no investigations were required.

E. SURVEY UNIT DATA ASSESSMENT An analysis of the direct sample measurement results, including the mean, median, standard deviation, and sample result range, is provided in Table 2. Positively detected values are bolded in the table. Since Co-60 and Cs-137 are the primary nuclides of concern, non-detect values for these nuclides were assumed to be present at the MDA. Of the 42 soil samples collected, 5identified Cs-137 activity below the DCGL value of 2.39 pCi/g. Additionally, one sample contained Co-60 below the DCGL. All other values were below the MDA.

Identified sample activities or Minimum Detectable Activities are listed in Table 2. The mean and median activities were less than the DCGLs for Cs-137 and Co-60. The average of the DCGL unity fiactions was 0.0949, indicating that the direct measurements averaged 9.49%/a of the DCGL limit.

For illustrative purposes, as indicated in LTP Section 5.9.3, a simplified general retrospective dose estimate can be calculated from the average residual contamination level by subtracting the mean fallout Cs-137 value (0.19 pCi/g)2 for disturbed soil from the survey unit sample mean activity (0.060 pCi/g). This would equate to an annual dose rate of 0.0 mrem/year.

Taking into account the average residual contamination level for Co-60, the annual dose rate would equate to 0.53 me/yia?. For purposes of demonstrating compliance with the radiological ciiteria for license termination and the enhanced State criteria, background activity was not subtracted from the sample analysis activity values.

F. ADDITIONAL DATA EVALUATION Attachment 4 provides additional data evaluation associated with this survey unit, including relevant statistical information. Based on survey unit direct measurement data, this attachment provides the Sign Test Summary, Quantile Plot, Histogram, and Retrospective Power Curve.

1. The Sign Test Summary provides an overall summary of design input (Table 1) and resulting calculated values used to determine the required number (N) of direct measurements (per LTP Section 5.42). The Sign Test Summary is a separate statistical analysis that also calculates the mean, median, and standard deviation of the direct measurements.

The critical value and the result of the Sign Test are provided in the Sign Test Summary table, as well as a listing of the key release criteria. The direct measurements clearly pass the Sign Test The subject release criteria have been satisfied. In addition, the sample standard deviation is smaller than the design sigma; therefore, no additional samples were required.

2 See Attachment E to Maine Yankee Procedure PMP 6.7.8 (Refcrence 2).

3 This annual dose equivalent is based on LTP Table 6-11 which shows the RA contaminated soil contribution (for soils contaminated at the DCGL) to be 7.67 rnremly. Therfore, the annual dose rate would equate to o.0599)

Annual DoseRate = 7.67x Om ) =03mrem ly FR-OII I-IS, Revision 0 PageS of 20

2. The Quantile Plot was generated from the unity data listed in Table 2. The data set and plot are consistent with expectations for a Class 1 survey unit. All of the measurements are below the DCGLs of 2.39 pCi/g for Cs-137 and 0.86 pCi/g for Co-60 for land inside the restricted area.

3. A Histogram Plot was also developed based on the unity data values. This plot shows a log-normal distribution with one outlier.

4. A Retrospective Power Curve was constructed, based on FSS results. The curve shows that this survey unit having a mean residual activity at a small fraction of the DCGL has a high probability ("power") of meeting the release criteria. Thus, it can be concluded that the direct measurement data support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and that the data quality objectives were met.

G. CHANGES IN INITIAL SURVEY UNIT ASSUMPTIONS ON EXTENT OF RESIDUAL ACTIVITY The survey was designed as a Class I land survey area; the FSS results were consistent with that classification. The direct measurement sample standard deviation was less than the design sigma. Thus, a sufficient number of sample measurements were taken and no additional measurements were required.

H. LTP CHANGES SUBSEQUENT TO SURVEY UNIT FSS The FSS of Survey Unit 15 was designed, performed, and evaluated in the April 2005 time frame. The design was performed to the criteria of the LIP Revision 4 (Reference 1). No subsequent LTP changes with potential impact to this survey unit need to be evaluated.

L CONCLUSION The FSS of this survey unit was designed based on the LI? designation as a Class 1 area.

The survey design parameters are presented in Table 1. The required number of direct measurements was determined for the Sign Test in accordance with the LTP. As presented in Table 2, all direct measurements were less than the DCGLs of 2.39 pCi/g Cs-137 and 0.86 pCilg Co-60. No measurements exceeded the unitized DCGL.

A Sign Test Summary analysis demonstrated that the Sign Test criteria were satisfied. The direct measurement sigma was determined to be less than that used for design, thus indicating that a sufficient number of samples was taken.

The Retrospective Power Curve shown in Attachment 4 confirmed that sufficient samples were taken to support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and the data quality objectives were met. Attachment 4 also revealed that direct measurement data-represented essentially a log-normal distribution with one outlier.

R-011 1-15, Revision 0 Page 6 of 20

The scan survey design for this survey unit was developed in accordance with the LTP Revision 4 (Reference 1) with significant aspects of the design discussed in Section B and Table 1. ISOCS scans performed at a distance of 3 meters in a systematic grid pattern throughout the survey unit and two concrete measurements taken at 2 meters from the surface did not identify activity above the scan investigation levels of 1.0 pCi/g Cs-1 37 and 0.36 pCi/g Co-60. Therefore, no investigations were required as a result of the scan process.

It is concluded that FR-01 1I Survey Unit 15 meets the release criteria of IOCFR20.1402 and the State of Maine enhanced criteria.

J. REFERENCES

1. Maine Yankee License Termination Plan, Revision 4, February 28,2005 provided by Maine Yankee letter to the NRC, MN-05-010

2. Maine Yankee Procedure PMP 6.7.8, FSS Data Processing and Reporting, Attachment E, Approach for Dealing With Background Radioactivity for Maine Yankee Final Status Surveys

3. Maine Yankee Calculation No. EC-003-04, Use of Canberra In Situ Object Counting System (ISOCS) for FSS Surveys FR-0111-15, Revision 0 Pige 7 of 20

Attachment 1 Survey Unit Maps FRO0111-15, Revision O Page 8 of 20

ae YCree*

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FR-0IIS, RevisionO Page 9 of20

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I FRO I I 1-15, Revision 0 Page 10 of 20 25m

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I FR-01I1-15, Revision 0 Page I I of 20 25m

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Attachment 2 Survey Unit Instrumentation FR-O111-I5,RevisionO Pae 13 of20

TABLE 2-1 INSTRUMENT INFORMATION ISOCS Detectors (Field Measurements)

Detector No. MDC (pCi/g) 7897 0.157 to 0.318 7607 0.169 to 0.333 7780 0.091 to 0.317 HPGe Detectors (Laboratory Analysis)

Detector No. MDC (pCi/g)

FSSI 0.0511 to 0.066

__FSS2 _ 0.0387 to 0.0661 TABLE 2-2 INSTRUMENT SCAN MDC, DCGL, INVESTIGATION LEVEL AND DCGLEmc Parameter . Instrument: ISOCS Comments ScanhMDC Cs-137: 0.157 to 0.333 30% DCGL

.o0 0.09 to 0_24 Approved DCGL for land 2.39 pCi/g Cs-137 DCGL 0.86 pCi/g Co-60 areas inside the Restricted Area (Reference 1)

Investigation Level 1.0 pCilg Cs-137 __ 3)

(ISOCS 2 i and C 3 i) 0.36 pCilg Co-60 (Reference 3) 4.27 pCilg Cs-137 DCGL x Area Factor for Design DCGLimc 4.54 pCi/g Clo760 Class 1 survey unit, per LTP 1.4p /- o6 Section 5.6.3 FR-01 11-15, Revision 0 Page 14 of 20

Attachment 3 Investigation Table (not used)

FR-01 I1-15, Revision 0 Page 15 of 20 Statistical Data FR-O111-15, Revision 0 Page 16 of 20

Survey Package FRI0i Unit 15 UNITY Soil Sign Test Summary Survey Package: FROI11 Survey Unit: 15 Evaluator DR DCGL.: 1.00E+00 Unity DCGL,,,: 1.80E+00 L1GR: 5.00E-01 Sigma: 5.56E-O1 (1.33 pCI~g /2.39 pCi/l)

Type I error 0.05 Type II error. 0.05 Nuclidel UNllY1 WI~pe ' NIA Zj': 1.645 Z14 : 1.645 Sign p: 0.788145 Calculated Relative Shit 0.8 Relative Shift Used: 0.8 Uses 3.0 if Relative Shift Is >3 N-Value: 33 N-Value+20%: 40 Number of Samples: 42 Median: 9.09E-02 Mean: 9.49E-02 Net Sample Standard Deviation: 2.83E-02 __ _

Total Standard Deviation: 2.83E-02 Sum of samples and reference Maxdmum:. 2.58E-01 Adjusted N Value: 42 S+ Value: ._ 42 Critical Value: 26 Sign tes ruf. Pass Sufficient samples collected: Pass .-

Maximum value <DCGL,: Pass Median value CDCGL,; . Pass Mean value <DCGL,: Pass Maximum value cDCGL.; Pass Total Standard Deviation <.Sgma: Pass_

Criteria comparison results: Pas3 The survey unit passes all conditions: Pass SU Passes F1ROi1.1SU154SONSIgn-UNtTY 4U25 8:58 AM FR-OI 11-13, Revision 0 Page 17 of2O

FROI II SU-1 5 Quantile Plot 0.300

. N 0.250 i ._

0.200 I I

I . ActVity 0.150 -Median (unitized)

I (unitized),

0.100 .I AW Go m 0.050 0.000 0 25 50 75 100 Percent L.

I L _ _....... .. _________________________________________________________________________________________

I

One-Sample T-Test Repoit Page/Date/Time 2 4127/05 8:22:50 AM Database C:AProgram Files\NCSS97\FR01 11 SU-1 5.SO Variable C2 Plots Section Histogram of FR-0111. SU-15 I

z FR-1 i 1-IS, Revision 0 Page 19 of 20

One-Sample T-Test Power Analysis Page/Date/Time 2 4/27/05 8:26:59 AM Chart Section Retrospective Power Curve 1.0- . . - -----

0.8- .

10.6

0. .. .:

0.2-0.0 0.0 0.2 0.4 0.6 0.8 1.0 Survey Unit Mean (unitized)

FR-O1N 1-15, Revision 0 Page 20 of 20

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-01 11 YARD WEST EXCAVATIONS SURVEY UNIT 16 Prepared By: Date: L5tfjLT. 0 gnature Printed Name Reviewed By: V - Date: 4Ll184 Independent Review - Signature

/Printed Name Appiewed By: I Date: + 1y/ ,6° 5 Indpenen Pnd RevieNat-Signature re Approved By: !

ae Printed Name/

Revision 0

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-0 11 YARD WEST EXCAVATIONS SURVEY UNIT 16 A. SURVEY UNIT DESCRIPTION FR-0 11 Yard West Survey IPpit 16 was located in the current Restricted Area yard, north of the former PAB. The 1273 m area encompassed the area of the former BWST and reserve station transformers (X14 & X16). The survey unit was bordered on the north by the Restricted Area fence line and the plant's south access road (FR-2900 Survey Unit 2). The survey unit was also bounded on the west by FR-01II Survey Unit 12, on the south by FR-0111 Survey Unit 15, and on the east by FR-01I I Survey Unit 20. Survey Unit 16 encompasses FR-0 11 Survey Unit 2, an area previously surveyed for FSS. The survey unit was centered near coordinates 623910E and 4078 1ON using the Maine State Coordinate System (West Zone) NAD 1927 as shown on map FRO 111-1 6 SITE. The location of the survey unit in relation to the Containment Building and the surrounding FR-0 11 survey units is shown on map FROI 11-16 REF (Attachment 1).

Survey Unit 16 was an area composed of soil, backfill, and various concrete pad and wall remnants. It included excavated trenches where storm drain piping was removed. The terrain was highly irregular and encompasses an area of 1273 m .

B. SURVEY UNIT DESIGN INFORMATION Survey Unit 16 met the LTP Revision 4 definition for a Class 1 survey unit. The survey unit design parameters are shown in Table l. Given a relative shift of 0.8, it was determined that 40 direct measurements were required for the Sign Test. Because the measurement locations were based on a systematic square grid with a random start point, the N=40 design led to a survey unit map with 42 locations which are illustrated on map FROII 1-1 6a (Attachment 1).

Direct measurements (soil and concrete samples) were collected from required locations and analyzed with laboratory gamma spectroscopy instrumentation.

In accordance with the LTP, scans covering 100% of the 1273 in2 area were required for the Class I survey unit. This was accomplished by use of an In situ gamma sE ectroscopy detector (ISOCS) configured at a 3-meter distance perpendicular to the soil surface to obtain overlapping 28-mi fields of view. There were 69 ISOCS scans of soil suffces. In addition, there were 47 ISOCS scans configured at a 2-meter distance with a 12.6-m field of view which were employed perpendicular to concrete surfaces, such as concrete walls and the sides of trenches. In some cases, ISOCS shots covered locations which included both soil and concrete. Appropriate geometries were selected based on the relative proportion of surface materials present These geometries include both the 2-meter as well as the 3-meter distances. Locations of the 116 survey scans are shown on maps FRO II 1-16b, 16c, 16d, 16e, and 16f (Attachment 1).

The ISOCS scans were configured to ensure 100% scan coverage of all exposed surfaces within Survey Unit 16. The survey instruments used arm listed by model and serial number in Attachment 2 (Table 2-1). Scan MDCs are also listed in Attachment 2 (Table 2-2) and are compared to the DCGL, the investigation level, and the DCGLEmc. The scan MDC is less than the scan investigation level, thus providing high confidence (95% or higher) that an elevated area would be detected in the scanning process. Further, since the investigation level was always less than te design DCGLEmc, no EMC sample size adjustment was necessary.

FR-0 11-16, Revision 0 Page 2 of 31

TABLE I SURVEY UNIT DESIGN PARAMETERS Survey Unit DesIan Criteria Bash Area 1273 m2 Class 1,< 2,O00 n2 Number of Direct Bsed on an LBGR of 1.2 pCig, sigmal of MeaNuembents Requ40 1.33 pCi/g and a relative shift of 0.8.

Measurements Required Type I = 11 I = 0.05 Sample Area 32m 1273 m2/ 40 = 32 m2 Sample Grid Spacing 5.6 m (32)1r Scan Grid Area ISOCS scans at 3m See Section B

_ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ an d 2 m_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Area Factor 1.7 Class I Area, LTP Table 6-12 Scan Area 1273 m 2 Class I Area- 100%

Scan Investigation Level 0 pOig s 60 ISOCS investigation levels (Reference 3)

DCGL 2.39 pCi/g Cs-137 (Reference 1) 0.86 pCi/g Co-60 (RfrneI 4.1 pCig Cs-137 DCGL x Area Factor for Class 1 survey Design DCGLEMC 1.5 pCi/g Co-60 unit, per LTP Section 5.6.3 C. SURVEY RESULTS A total of 42 direct measurements were performed in Survey Unit 16. Seven samples contained detectable Cs-I 37 with levels of residual activity greater than the MDA but below the DCGL. Two samples (S005, S008) contained detectable Co-60 activity. All other measurements were below the MDA. The results are presented in Table 2. Per Table 5-7 of the LTP, the Direct Investigation Level for this Class I area was equivalent to the DCGLEMc which is 4.1 pCi/g Cs-137 and 1.5 pCilg Co-60. Investigations were performed for direct samples S005 and S008 despite being less than the LT? investigation levels. The investigation results are discussed in Section D.

ISOCS gamma scans were performed at 116 locations using a Scan Investigation Level of 1.0 pCi/g Cs-137 and 0.36 pCi/g Co-60. The gamma scans were performed for a sufficient count time to achieve a Minimum Detectable Activity (MDA) of approximately 35% of the DCGL. All identified scan activity levels and MDAs were below the investigation levels, except for C040. The Co-60 value for this scan exceeded the Scan Investigation Level of 0.36 pCi/g and was thus investigated. The Cs-137 result for this scan was much less than the investigation level.

LTP Revision 4, Table 5-IC for RCA Yard West, ROIOO FR-0111-16, Revision 0 Page 3 of 31

TABLE 2 DIRECT MEASUREMENTS Sample Number Ca-137 Uncertainty Co-60 Uncertainty Unitized Value (pk1g) (PCIg) (pCUgi) (pCig) of Unity Rule FROII161SOOI < 6.44E-02 < 6.35E-02 _ I.OIE-OI FROI11161S002 < 7.67E-02 < 7.38E-02 1.18ErOI FR0111161S003 < 8.34E-02 < 7.42E-02 121E-OI FROII161SO04 < &31E.02 < 7.70E-02 1.24E-OI FROII1161SO05 1.53E+00 1.20E-01 5.39E-01 4.73E-02 1.27E+00 FR0111161S006 < 639E-02 < 5.07E-02 8.57E-02 FRO1III16S007 < 6.25E.02 < 7.14E-02 1.09E-OI FROI1161Soos 6.61E-01 JBES-02 2.65E-01 4.82E-02 S15.E-o FR0111161SOO9 I.29E-01 3.92E-02 < 6.90E-02 1_34E-O1 FROI1161SO10 < 7S8E-02 < 7.17E-02 I.ISE-O1 FROIII161SOII < 6.13E-02 c 6.65E-02 1.03E-OI FROII161SO12 < 5.84E-02 < 6.00E-02 9A2E-02 FROII161SO13 < 7.52E-02 < 7.00E-02 1.13E-O0 FROII161SO14 < 6.62E1O2 < 6.98E-02 1.09E-41 FRO111161SOI5 < S.23E-02 < 5.94E-02 9.10E-02 FROIII161SO16 IA6E-01 3ASE-02 < 7.24E-02 1.45E-O1 FRO11I161SO17 < 6.93E.02 < 6.66E-02 1.06E1O0 FRO11II161S08 < 8.1IE-02 < 7.95E-02 1.26E-01 FROIII161SOI9 < 6.13E.02 < 6.47E-02 A, I.OIE-OI FR01161S020 < 7A7E-02 < 7.70E-02 1.21E-OI FR0II 161S021 < 6.83E-02 < 6.29E-02 1.02E-OI FR0111161S022 < 8.76E-CQ c 6.78E-02 _ _ 1.1SE- 1 FROI1 161S023 < 6.14E.02 < 7.40E-02 1.12E-OI FRO1I1161SO24 < 7.21E.02 < 6.17E-02 1.02EOI FR0111161S025 < 5.68E-02 < 6.54E-02 9.98E-02 FROIII161S026 < 5.65E302 c 5.53E1-02 _ S.79E-02 FR0111161S027 c 6.53E-02 c 6.29E-02 1.OOE-O1 FRO111161SO28 < 6.10E.02 < 5.SE.02 _____ 9.04E-02 FR0111161S029 < 4.08E1-02 < 4.67E-02 C 7.14E-02 FRO1III161SO30 < 4.66E-02 < 5.26E-OQ _ 8.07E-02 FR01116IS031 c 422F-02 c 4.04E-02 6.46E-02 FRID111161S032 < 4.44E-02 < 4.79E-02 7A3E-02 FR0111161S033 < 4.79E-02 < 4.99E-02 7.81E-02 FROIII161S034 < 4.5E1-02 < 5.01E-02 7.73E-02 FR0111161S035 < 4.09E.02 < 4.27E-02 6.68E-02 FR0111161S036 < 4.98E-02 < S.04E-02 7.94E-02 FROII1161SO37 < 5.69E-02 < 5.53E-02 8.81_E.02 FROIII161SO38 755E.02 3.62E-02 < 6.31E-02 I.05"EO1 FRO 111161S039 2.17E-01 4.69E-02 < 7A9E-02 1.78E-O1 FR0111161S04O < 6.18E-02 < 7.12E-02 l .09E-O1 FRO1161S041 LSOE-01 4.56E-02 < 7.69E-02 1.65E-01 FR0111161S042 < 5.62E-02 < S.68E-02 8.96E-02 Mean 1 22E-01 7.92E-02 1.45E-01 Median 6A2E-02 6.51E-02 1.03E-Ol Standard Deviation 2.43E-01 7.97E-02 1.94E-Ol 4.081E-02 to 4.04E-02 to 6.46E-02 to

_ 1__

1.53E4+00 539E-01 127E+OO "e indicates MDA value. Bold indicates positive detection value.

FR-O1 11-16, Revision O Page 4 of31

D. SURVEY UNIT INVESTIGATIONS PERFORMED AND RESULTS Based on the scan results, one investigation was required at C040. The result of this scan was a detectable Co-60 value of 0.40 pCi/g which exceeded the Scan Investigation Level of 0.36 pCi/g. The Cs-137 value of 0.54 pCi/g was 54% of the Scan Investigation Level of 1.0 pCi/g. In addition, there were two direct measurements (soil samples S005 and S008) which were investigated. Direct measurement SODS contained detectable Co-60 at 0.54 pCi/g and Cs-137 at 1.53 pCi/g, yielding a unity value greater than one (1.27). Direct measurement S008 contained detectable Co-60 of 0.27 pCi/g, Cs-137 at 0.66 pCi/g, and a unity value of 0.58. A decision to investigate location S008 was made based on a review of the survey data and professional judgment. All investigations consisted of a series of 70 cm ISOCS measurements and soil or concrete sampling.

Direct measurement location S008 was investigated by taking six ISOCS measurements (SOOSE was inaccessible due to the proximity of the BWST pit) and three samples (S00813, D, and F). The arrangement of the investigation measurements is indicated on map XROI 11-16a. As shown in Table 3-1 of Attachment 3, the average of the ISOCS measurements and sample results were all less than the DCGL. However, one sample result exceeded the unitized DCGL (1.19). Based on this result, a decision was made to remediate a 3 m x 3 m area in the vicinity of S008. The remediated area was resurveyed by taking five samples for laboratory analysis and one ISOCS measurement 2 meters from the surface. The as-left survey measurements were all much less than the applicable DCGLs. The arrangement for the final measurements is shown on map XROI 1-1 6c. The final measurement results are shown in Table 3-2 (Attachment 3).

Similar to S008, direct measurement location S005 and scan location C040 were investigated by taking seven ISOCS measurements as indicated on maps XRO1I 1-16a and XRO I 1-16b.

In addition, three samples were obtained around S005 (SO05B, C, and E) and four samples around C040. As shown in Table 3-1 of Attachment 3, the average of the ISOCS measurements and sample results were all less than the DCGL. However, various measurements exceeded the unitized DCGL at both locations. A review of the survey data and an inspection of the survey area indicated that the contamination extended between S005 and C040. Based on this, a decision was made to remediate the area shown on map XRO1 11-16d. The remediated area was resurveyed by taking six ISOCS measurements and six corresponding volumetric samples. The as-left survey measurements were all well below the applicable DCGLs. The arrangement for the final measurements is also shown on map XR011 1-16d. The final measurement results are shown on Table 3-2 (Attachment 3).

FR-OI 11-16, Revision 0 Page 5 of 31

E. SURVEY UNIT DATA ASSESSMENT An analysis of the direct sample measurement results, including the mean, median, standard deviation, and sample result range, is provided in Table 2. Positively detected values are bolded in the table. Of the 42 soil samples collected, seven identified detectable Cs-137 activity below the DCGL value of 2.39 pCi/g and two samples identified detectable Co-60 activity below the DCGL value of 0.86 pCi/g. All other values were below the MDA.

Identified sample activities or Minimum Detectable Activities are listed in Table 2. The mean and median activities were less than the DCGLs for both Cs-1 37 and Co-60. The average of the unity values was 0.145 pCi/g, indicating that the direct measurements averaged 14.5% of the DCGL limit Two of the direct measurements, S005 and SOOS, were investigated. S005 had a unity value exceeding one, and S008 was evaluated primarily because of it's proximity to S005. In addition C040 was investigated because it's Co-60 measurement result exceeded the Scan Investigation Level. The investigation results were discussed in Section D.

For illustrative purposes, as indicated in LTP Section 5.9.3, a simplified general retrospective dose estimate can be calculated from the average residual contamination level by subtracting the mean fallout Cs-I 37 value (0.19 pCi/g)2 for disturbed soil from the survey unit sample mean activity (0.122 pCi/g). This would equate to an annual dose rate of 0.0 mrem/y.

Taking into account the average residual contamination level for Co-60, the annual dose rate would equate to 0.71 mren/yea. Also, for purposes of demonstrating compliance with the radiological criteria for license termination and the enhanced State of Maine criteria, background activity was not subtracted from the sample analysis activity values.

F. ADDITIONAL DATA EVALUATION Attachment 4 provides additional data evaluation associated with this Survey Unit, including relevant statistical information. Based on survey unit direct measurement data, this attachment provides the Sign Test Summary, Quantile Plot, Histogram, and Retrospective Power Curve.

I. The Sign Test Summary provides an overall summary of design input (Table 1)and resulting calculated values used to determine the required number (N) of direct measurements (per LTP Section 5.4.2). The Sign Test Summary is a separate statistical analysis that also calculates the mean, median, and standard deviation of the direct measurements.

The critical value and the result of the Sign Test are provided in the Sign Test Summary table, as well as a listing of the key release criteria. The direct measurements clearly pass the Sign Test, although a unity value exceeded one. This point as well as another were investigated as discussed in Section E. All other subject release criteria have been satisfied. In addition, the sample standard deviation is smaller than the design sigma; therefore, no additional samples were required.

2 See Attachment E to Maine Yankee Procedure PMP 6.7.8 (Reference 2).

This annul dose equivalent is based on LTP Table 6-11, which shows the RA contaninated soil contribution (for soils contaminated at the DCGL) to be 7.67 mrnrly. herefore, the annual Co-60 dose rate would equate to (0.0792)

Annual DosePWte =7.67x 0 =0.7lmremly 0~.86)

FR-Cl 11-16, Revision 0 Page 6 of31

2. The Quantile Plot was generated from the unity data listed in Table 2. The data set and plot are consistent with expectations for a Class I survey unit. One of the measurements exceeded the unitized DCGL for land inside the restricted area.

3. A Histogram Plot was also developed. This plot shows a log-normal distribution with two outliers.

4. A Retrospective Power Curve was constructed, based on FSS results. The curve shows that this survey unit having a mean residual activity at a small fraction of the DCGL has a high probability ("powerz) of meeting the release criteria. Thus, it can be concluded that the direct measurement data support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and that the data quality objectives were met.

G. CHANGES IN INITIAL SURVEY UNIT ASSUMPTIONS ON EXTENT OF RESIDUAL ACTIVITY The survey was designed as a Class 1 land survey area; the FSS results were consistent with that classification. The direct measurement sample standard deviation was less than the design sigma. Thus; a sufficient number of sample measurements were taken and no additional measurements were required.

IL LTP CHANGES SUBSEQUENT TO SURVEY UNIT FSS The FSS of Survey Unit 16 was designed, performed and evaluated in the March 2005 time frame. The design was performed to the criteria of the LTP Revision 4 (Reference 1). No subsequent LTP changes with potential impact to this survey unit need to be evaluated.

I. CONCLUSION The FSS of this survey unit was designed based on the LTP designation as a Class I area.

The survey design parameters are presented in Table 1. The required number of direct measurements was determined for the Sign Test in accordance with the LTP. As presented in Table 2, all direct measurements, except for S005, were less than the unitized DCGL. There was an investigation of two direct measurements. The areas were remediated. The as-left measurements were all less than the unitized DCGL.

A Sign Test Summary analysis demonstrated that the Sign Test criteria were satisfied, although a unity value exceeded one. An investigation survey was performed to bound the contamination. The area was remediated and verified that no activity existed greater than the DCGL. The direct measurement sigma was determined to be less than that used for design, thus indicating that a sufficient number of samples was taken.

The Retrospective Power Curve shown in Attachment 4 confirmed that sufficient samples were taken to support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and the data quality objectives were met. Attachment 4 also revealed that direct measurement data represented essentially a log-normal distribution with two outliers.

FR-O 1-16, Revision 0 Page 7 of 31

The scan survey design for this survey unit was developed in accordance with the LTP Revision 4 (Reference I) with significant aspects of the design discussed in Section B and Table 1. ISOCS scans performed at a distance of 2 or 3 meters in a systematic grid pattern throughout the survey unit and identified one measurement (at C040), a Co-60 value, which was above the Scan Investigation Level of 0.36 pCi/g Co-60. There were no Cs-137 scan measurements which exceeded the Scan Investigation Level of 1.0 pCi/g Cs-1 37. Post remediation data for C040 indicated no activity in excess of the DCGL.

It is concluded that PR-0 11 Survey Unit 16 meets the release criteria of IOCFR20.1402 and the State of Maine enhanced criteria.

J. REFERENCES

1. Maine Yankee License Termination Plan, Revision 4, Februaxy 28,2005 provided by Maine Yankee letter to the NRC, MN-05-010

2. Maine Yankee Procedure PMP 6.7.8, FSS Data Processing and Reporting, Attachment E, Approach for Dealing With Background Radioactivity for Maine Yankee Final Status Surveys

3. Maine Yankee Calculation No. EC-003-04, Use of Canberra In Situ Object Counting System (ISOCS) for FSS Surveys FR-OI11-16, Revision o Page 8 of 31

Attachment 1 Survey Unit Maps FR-O111-16, Revision 0 Page 9 of 31

623.000 E 623.500 E 624,000 E 624. 500 E 625. 000 E 625. 500 E

' 626,000 c Note: Grid based on Maine State Coordinate System (West Zone) NAD 1927 l

Decommissioning Team lMaine Yane IDecommissioningrojectrvey Date: 3130105 Survey Type: El Charactefzation 0 Turnover DFMal Status Survey Sumrey Area Name: Yard West Soils Final Status Survey FRO11I SU1 6 Reference Map FRFOIII sub9 SW/ fV5 K WTH si FR OI II S uMs1 2

? sMZ W / ISU14 1 FFRO20 d] = SU6 /5

\ft 127 a"~a 0 _

50_ 100

= _ _ 000001-

Decommissioning Team 1Maine YankeeDecommissioningProjedSurveyForm IDate: 3/31105 Survey Tpe: Characterization 0 Tum'over EXFMal Status Survey i Survey Aiea Name: Yard West Sails Final Status Survey FRO111 SU16 Direct Points 001 - 042 sAo so'N SA58 So9 SAO Sc(21 SA24 l

i PROf1 I _I FR-01 -16, Revision 0 Page 12 of 31 Area = 1273

Maine Yankee I IMap ID*. FR0111-16b DecommissioningTeam lMaineYankeeDecommissoningProjectSurveyForm Date: 3/31106 Survey Type: 0 Characedta on 0 Tumover CM Fil Stalus Survey i Survey Area Namr: Yard West Sols Final Status Survey FRO111 SU16 ISOCS Soil Scans S001 - S059

-Nf Locations S001-SO08 are positioned as IndIcated. The remaining shots follow the typical 24 pattem starting at S001. Locations designated wffl an arrow Inricate,shots that hel \>4 outide the survey area or on concrete, and then were shifted Intoward the boundary.

SIPS2 NV

/*11-6 RcisoN O rotal Survey UnitArea 1273sq-rn m ~

Decmmssioning Team lMane Yankee DecommissioningProjectSurvey Form l Date: 411/05 Survey Type: O Characteriztlon O Tumover DFinal Stats Surveyl Survey Area Name: Yard West Soils Final Status Survey FRO111 SU16 ISOCS Concrete Scans COO1 - C044 Floor Scans, X-Fmr Pad N -

/ I

\ -.

0 I

I I6 Typical ISCOS Spacing as (Maxkmum)

O.91rn I Locations CO01-C019 are spaced per the Typical ISOCS Spacing detail, with the exception of C006,C007 and C019 which were shifted so that they are located 1ft off the inside of the pit wall.

Locations C020-C023 are on the same axis as the adjacent shots, but also are located 1ft off the --<C Inside of their respective walls.

FR-0 I 1-16, Revision 0 Page 14 of 31

Deommmissfoning Team lMaine Yankee DecommissioningProjectSurve Form lros 4i1/05 Survey Type: 0 Charactelrzation 0 Turnover 0 Final Stts Survey I Survey Area Name: Yard West SoUs Final Status Survey FRO111 SU16 ISOCS Soil Scans S060 - S069 Locations S060GS067 are positioned on 4.54m centers in trench beginning at 2.4m from SU boundary on each end.

l FR-01 11-16, Revision 0 I rvey nUtea r =1

Maine Yankee I ap ID#~: FRO1I i-16e DeoommIssioningTeamn MaineYankeeDecommissioningProjectSurveyFormIDat: 4/105 Suwoy Type: 0 Charmtekzetian 0 Tumove' X FMal Status Surey iSurvey Area Name: Yard West Sofs Final Status Survey FRO111 SU16 Angled ISOCS Concrete Scans C047 ing Crevice between ledge wall and PAB wall.

Angled ISOCS Scan Location C047.

FR0111-16,RevisionO Total Survey itAeIf3ea = 1273 sq-m

Maine Yankee .ap m is; FRO111-16f Decommissioning Team Maine Yankee DecomnissioningProjectSurvey Form Date: 411105 Survey Type. 0 Charadteration 0 Turnover E Final Staus Survey I Survey Area Name: Yard West Soils Final Status Survey FRO111 SU16 ISOCS Concrete Scans C045 - C046 Floor Scans, X-Fmr Pad a.<---

'4. A ~- -------

5..---5 Locations C045 & C046 are positioned In the center of the holes In the transformer foundation.

FR- 11C16. Revision 0 Page 17of31

DecommissloningTeam lMaineYankeeDecommissionlngProjectSureyFormDate: 415105 Swmy Type: [I Charcerztn 0 Tumnome X RWe satab Survey I Survey Ama Name: Yard West Soils Final Status Survey Investigation XR011 1 SU 16 Direct Points S005 - S008 I'I L Sal1 : WS3 Kz 00(

FR-01 11-16, Revision 0 Page 18 cf31

Maine Yankee _ _ Map ID#XR0111-16b Decommissioning Team Maine YankeeDecommissioningProjectSurvey Form Date: 4/5/05 Survey Type: 0 Characbtation 0 Turnover E FWai Status Sway I Survey Area Name: Yard West Soils Final Status Survey investigation

-a -. I XR0111 SU16 ISOCS Concrete Scan A&r4~- .-I Location C040 I

Original FSS Scan Locations I i Ii

.5-.

- - =~ III Ad C040(C)

I i

i C040(A) I

/

I I

, I _- - -_

Investigation Investigation

Sican Locations Sample Locations

-FR- %--

11-16;jeywiono- -. -

Page 19of31

Maine Yankee Map ID#:XRO111-16c Decommissioning Team Maine Yankee DecommissioningProjectSureyq Form Date: 416/05 Survey TypO: O Charactersation 0 Tumover E Fhnal Status Survey I Survey Area Name: Yard West Soils Final Status Survey Investigation XR01 11 SU16 Direct Points S005 - S008

-- 'T S yurr m 3m sam centerd around Invatlgalon Location 800O(0).

( 008(G) Is located 0.7Gm E of original FSS Bg Suample Locatlon 8008 Th a" smplee at location o odginal FS8 Boll Smple 800 8005(0)-Surtaces ampl SC08(H) .612-Depth Sunple S005(G),\

600(H)

FR-0111-16, Revision O Page 20 of 31

Maine Yankee r MImap iu C.AR0iii-1bi Decommlssioning Team Maine YankeeDecommissioningProjectSurveyForm Date: 4r705 SuveY TPe: EJ Characterzation 0 Turnover 9 Final State Survy ISurvey Area Narno: Yard West SofIs Final Status Survey Investigation XR01 11 SUI6 Remediated Area 1 7; L -' '-I 1 0~1 1 S006 004

~ zrnn' Remediated 27.5m from SU 16

,L., SE~omer // Post Remediation 2m ISOCS Scans 1 6 so - , I stills FR-O1 11-16, Revision 0

P21 of --.

Attachment 2 Survey Unit Instrumentation FR-O1 I 1-16, Revision 0 Page 22 of 31

TABLE 2-1 INSTRUMENT INFORMATION ISOCS Detectors (Field Measurements)

DetectorNo. l_MDC(pCi/g) l 7607 j 0.10 to 0.48 7780 .0.14to 0.38 HPGe Detectors (Laboratory Analysis)

Detector No. MDC (pCi/g)

FSS1 0.04 to 0.09 FSS2 0.04 to 0.08 DEI2 T 0.06 to 0.07 TABLE 2-2 INSTRUMENT SCAN MDC, DCGL, INVESTIGATION LEVEL AND DCGLnic Parameter Instrument. ISOCS Comments ISOCS (pCi/g)

ScanMDC 0.152 to 0.484 Cs-137 - 35% DCGL 0.102 to 0.299 Co-60 2.39 pCi/g Cs-137 Approved DCGL for land DCL0.86 pCi/g Co-60 areas inside the Restricted

._ ._ Area (Reference 1)

Investigation Level 1.0 pCi/g Cs-137 (Reference 3)

(ISOCS Q 3m, 2m) 0.36 pCi/g Co-60 (Reference_3) 41 i/ C DCGL x Area Factor for Design DCGLEMc 1.1 pCi/g Cs-137 Class 1 survey unit, per LTP 1.5p~g Scton 5.6.3 FR-O 11-16, Revision O Page 23 of 31

Attachment 3 Investigation Table FR-OI I1-16, Revision 0 Page 24 of 31

TABLE 3-1 INVESTIGATION TABLE

]NITIAL SAMPLES INVESTIGATED _NVESIGATION AVERAGE CU RESULTS Initial Results (pCl/9) Direct Samples ISOCS scans Sample Number Co Cs-137 Co-60 Cs-137 Co-60 Cs-137 Results Uncertainty_ ResutI Uncertain S005 ( ) 5.392-01 4.732-02 1.53E1+00 1.203-0 1 2.332-01 4.392-01 2.412-01 4.122-01 S008 (Direct) 2.65E-01 4.822-02 6.61101 8.88EA02 4.352-01 4.392-01 2.152301 3.572-01 C040 (Scan) 3.97-01 4.09-01 I 54I; 3.981-01 3.72F,01 7.IOE-01 3.12E-01 5.423-01 FR-0111-16, Revision 0 Page 25 of3l

TABLE 3-2 AS-LEFT SURVEY RESULTS Direct ResUls (pC!g) ISOCS Scan Results (pCIg/)

Sample Number Co-60 Cs-137 Cl-0 Cs-137

_R___ Results Uncertainty Results Uncertainty Results Results S008-VS-G 1.271-01 6.322-02 1.79E-01 5.892-02 <2.40E-01 <1.90E-01 S008-VS-H <1.17E-01 1.281-01 5.02e-02 nla n/a S008-VS-I <9.90E-02 8.872-02 5.38E-02 n/a n/a S008-VS-J <5.69E202 1.20E-01 3.05E-02 nra n/a S008-VS-K <6.932-02 _ 1.221-01 3.842-02 n/a n/a S070 <6.12E-02 1.291-01 3.442-02 <1.992-01 <3.23E-01 S071 I1A31-01 3A7E-02 2.802-01 4.041-02 <2.03E-01 <1.65E-01 S072 2.122-01 3.051-02 3.99E-01 5.292-02 <.03B-01 <2.132-01 S073 <4.74E-02 _ 1.1 11-01 2.511-02 <2.20E-01 <3.162-01 S074 <6.582-02 1.522-01 3.521-02 Q2.072-01 c2.96E-01 S075 <5.13E-02 <5.52E-02 <1.662-01 <3.19E-01 I FR-41 11-16, Revision 0 Page 26 of 31 i

I

Attachment 4 Statistical Data FR-O1 11-16, Revision 0 Page 27 of 31

Survey Package FRO111 Unit 16 UNITY Soil Sign Test Summary Survey Package: FROi 1 Survey UnIL- 16 Evaluator Andy Olsen DCGI 1.OOE+00 Unity DCGL.: 1.70E+OO LBGR: 5.00E-01 Sgma: 5.56E-01 (1.33 pCl~g 12.39 pCAg)

Type I error: 0.05 Type II errorl 0.05 Nuclide: UNITY_

Sign p: .788145 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Calculated Relative Shf ~0.8 ____________

Relative Shift Used: .0.8 Uses 3.0 If RelativO Shift Is >3 N-Value: 33N N-Value+20%: 40 Number of Samples: 42 Median: 1.03E-01 Moan: 1.43E501 Net Sample Standard Deviation: 1.94E-01 Total Standard Deviation:l 1.94E-01 iSum of samples and reference Maxpmum: 0.27E8001 Adjusted N Value: 42 N-Value: 41 Critical Value: 26 Sign test results: - PaSs Su samples ucient collectedi pass Maximum value .CDCGLV.W Investigate See Investigation XRO1 11-1 6 Median value dDCGL. Pass0 Mean value 1DCGL-Pass Maximum pDCGLa.b value : Pass Total Standard Deviation b1SEgma: Pass ofsamplesandreference Criteria comparison results:. investi See Investigation XRO1 11-16 The survey unit passes all conditionsI Investigate Survey Unit Passes FPRO1 I1-SU16-WSJgrA1N1TYxc~s 425 104 PM FR-Oi 11-16, Revision O Page 28 of 31

FRO11I SU-16 Quantile Plot 1.40E+00 1.20E+00 000 1.OOE+00 -. --. .___ __ ._.. I

9 U-10-8.OOE-01 i

Activity (unitized)

-'O .1

'-Median (unitized)

I U- 6.OOE- 01

9 0 4.OOE-01 2.OOE-01

- I I - - I - __ . .-

O.OOE+00 0 25 50 75 100 Percent

One-Sample T-Test Report Page/DatetTime 2 4/5105 7.06:29 AM Database C:AProgram Files\NCSS97\FR0111SU-16.SO Variable C2 Plots Section Histogram of FR-0111. SU-16 1

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FR-01 11-16, Revision 0 Page 30 of 31

One-Sample T-Test Power Analysis Page/Datelme 2 415105 7:04:30 AM Chart Section Retrospective Power Curve 1.0-

0.8 I-

.I 0.6

\.I 0.4- : i 0.2-0.0 _ I I I I 0.1 0:3 0'5 0:7 0:9 1'1 Survey Unit Mean (unitized)

FR-O0 11-16, Revision 0 Page 31 of 31

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-2600 ELECTRICAL DUCT BANKS AND MANHOLES SURVEY UNIT 1 Prepared By: Date:

FSS Engineer - Signature Printed Name

<_ . ..I. lD-Reviewed By: Date:

PRSpech Printed Name Reviewed By: 6Datc:1.4prt 0 Inde endent Review - Signature Approved By: i Date: d/7y5

,hpennte^;*6y- ignatr

/ PinodNamed Approved By: Date: fzel FSS, MOP - Signature 4Prit ed. RNe Printed Name Revision 0

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-2600 ELECTRICAL DUCT BANKS AND MANHOLES SURVEY UNIT 1 A. SURVEY UNIT DESCRIPTION The survey area consists of electrical cable duct banks located throughout the developed portion of the Maine Yankee site both inside and outside of the Restricted Area (RA).

Survey Unit 1 encompasses the entire survey area. The accessible portions of Survey Unit I are the concrete manhole (MW) and handhole (11) structures. These structures are essentially concrete vaults. There are seven manhole vaults and twelve handhole vaults in Survey Unit 1. Total surface area of Survey Unit 1 is approximately 5,396 m2. This area includes the interior surface area of the conduits and vaults.

Survey Unit 1 consists of the remaining duct banks, manholes, and handholes located within the North end of the developed site (also known as Balance of Plant Land) and the North end of the Restricted Area. Survey area FR-2600 is shown in relation to the Maine State Coordinate System (West Zone) NAD 1927 on survey map FR 2600-1 SITE (Attachment 1).

The duct bank manholes and handholes of Survey Unit I are shown on map FR2600-1 REF (Attachment 1).

B. SURVEY UNIT DESIGN INFORMATION The majority of the remaining duct banks, MHs, and HHs were located outside the RA during plant operation and were not used to transport any contaminated media. During site demolition, removable contamination samples were obtained when possible on electrical cables as they were removed from the duct banks. The cable surveys, although limited in quantity, provided a qualitative indication of inaccessible contamination levels present within the conduits with negligible results. Based on these facts, it was judged that there is a low probability that the duct bank system would contain residual contamination at levels above a small fraction of the DCGL and the system was designated a Class 3 survey unit.

The accessible surfaces of this survey area consist mainly of the concrete manhole and handhole vaults. The vaults generally make up the low points for this survey area. As such, the MHs and HHs have the highest potential for containing residual radioactivity and data obtained in the vaults should be representative of the residual activity in the duct banks' conduits. Therefore, as discussed previously with the NRC, the measurements obtained in this survey unit will be taken on the interior surfaces of the MH and HH vaults.

Prior to surveying manhole MH-1 and handhole HH4 it was discovered that the top and side of the manhole were damaged and the handhole had been removed. An evaluation concerning potential contamination of MH-1 as a result of the broken top/wall concluded that the manhole was not impacted by plant-derived materials and met the requirements for a Class 3 area (Reference 6). Due to the removal of HH-4, one direct measurement had to be relocated. The new measurement location was determined randomly consistent with the following discussion.

FR-2600-o1, Revision 0 Page 2 of 33

The survey unit design parameters are shown in Table 1. Given a relative shift of 3.0, it was determined that 14 direct measurements were required for the Sign Test. The measurement locations were based on a randomly generated point as illustrated on maps FR2600-la through Ik (Attachment 1). All direct measurements were obtained using a Ludlum 43-68 detector. Although not part of the release decision, soil samples were also collected from locations where soil or sediment existed in the bottom of the vault and analyzed by laboratory gamma spectroscopy instrumentation.

In accordance with the LTP, scans covering 1-10% of the 5396 m2 area were required for the Class 3 survey unit. This was accomplished by use of an in situ gamma spectroscopy detector (ISOCS) configured to ensure 100% scan coverage of the accessible handhole and manhole surfaces. The resulting fields of view ranged between 4.2 m2 and 39.0 m2 depending on the size of the vault. The ISOCS detector was positioned perpendicular to the floor surface. Typical configurations of the ISOCS survey scans are shown on illustrations FR2600-11,FR2600-lm, and FR2600-ln.

As previously stated, the ISOCS scans were configured to ensure 100%h scan coverage of the accessible surfaces of the manholes and handholes within Survey Unit 1. With the exception of manhole MH-l (located inside the restricted area), the ISOCS scans were performed with a detector using no collimation. Manhole I required a different ISOCS detector using the 180 degree shield configuration with the back shield installed, to eliminate possible streaming effects from the adjacent Class I FR-01 I I Survey Unit 16. The total area scanned was approximately 268 m2 or 5% of the survey unit area.

Background values were established based on ambient background values in the survey unit.

Due to safety considerations in accessing the MH and HH interiors, the average ambient background value shown in Table 1 was determined retrospectively from data obtained during the survey. This value was used to establish the net activity for the direct measurements. All daily background values fell within the procedural tolerance of the Table 1 average value.

The survey instruments used are listed by model and serial number in Attachment 2 (Table 2-1). Scan MDCs are also listed in Attachment 2 (Table 2-2) and are compared to the DCGL and the investigation level. The scan MDC is less than the scan investigation level, thus providing high confidence that an elevated area would be detected in the scanning process.

FR-2600-01, Revision 0 Page 3 of 33

TABLE 1 SURVEY UNIT DESIGN PARAMETERS Survey Unit Design Criteria Basis Area 5396 m2 Class 3, no limit Based on an adjusted LBGR of 8,876 Number of Direct 14 dpm/100 cm 2 , sigma' of 308 dprnl/00 Measurements Required cm 2 , and a relative shift of 3.0.

Type I = Type I = 0.05 Sample Area NA Class 3 Area Sample Grid Spacing NA Class 3 Area ISOCS scans with fields of Scan Grid Area view between 42 n2 and See Section B 39.0 mi2 Area Factor NA Only required for Class 1 areas Scan Area Approximately 268 m Class 3 Area 100/%

Background

43-68 Direct (concrete) 320 cpm Ambient only ISOCS Scan Investigation Level 50% DCGL See Table 2-2, Attachment 2 DCGL 9,800 dpm/100 cm2 Reference 1 C. SURVEY RESULTS A total of 14 direct measurements were performed in Survey Unit 1. All results were less than the DCGL. Upon review of the direct measurement data, it was noted that the technician had made a comment that several of the direct measurement locations were "damp." An efficiency correction for damp concrete (0.049 vs 0.13 c/d) was applied which resulted in several of the direct measurement results exceeding the investigation criterion (greater than 0.5 DCGL). In the case of the duct banks, the scan surveys were performed by in situ gamma spectroscopy, which is not affected by dampness, with no evidence of plant-derived radionculide activity present above the investigation level. Because the nuclide-specific scan survey did not identify either Cs-137 or Co-60 (or any other gamma emitter),

the direct measurement results were not further investigated.

ISOCS gamma scans were performed in 19 vaults using an investigation level of 4,430 dpxnll 00 cm2Cs-137 and 470 dprnml00 cm 2 Co-60 (approximately 50% oftheDCGL). The gamma scans were performed for a sufficient count time to achieve a Minimum Detectable Activity (MDA) of approximately 10% of the DCGL All scan activity values were below the investigation levels. An evaluation was performed to determine the attenuation effects of water and sediment on the floor. The evaluation concluded that water levels (0.5" to 2.0') in the vaults did not cause the MDAs to exceed the prescribed investigation level. The evaluation also concluded that for the worst case sediment depth (5.0"), the MDA exceeded the investigation level for the floor area However, the associated sediment sample showed no detectable Co-60 or Cs-137. Therefore, no investigation surveys were required based on the scan results.

I LTP Revision 3, Table 5-IB, Reactor MCC and Control Room, considered In determining sigma since durt banks located inside and outside RA.

FR-2600-01, Revision 0 Page 4 of 33

TABLE 2 DIRECT MEASUREMENTS Gross Activit Net Aictivity Sample Number (dpmllOO cm) (Ambient Background Subtracted)

Note 1 -(dpmllOO cm2) Note 2 FR2600013COOlBD4368 2,961 1,007 FR2600013C002BD4368 2,698 745 FR2600013C003BD4368 6,511 1,328 FR2600013C004BD4368 2,656 702 FR2600013C005BD4368 4,811 2,857 FR2600013C006BD4368 7,483 2,300 FR2600013C007BD4368 7,775 2,592 FR2600013C008BD4368 4,231 2,277 FR2600013C009BD4368 7,515 2,332 FR2600013COlOBD4368 6,689 1,506 FR2600013COl lBD4368 5,572 389 FR2600013C012BD4368 7,564 2,381 FR2600013C013BD4368 3,150 1,197 FR2600013C014BD4368 3,187 1,233 Me an 5,200 1,632 Median 5,91 1,417 Standard Deviation 2,037 803 -

Range 2,656 to 7,775 389 to 2,857 NOTES

1. A dry concrete surface eMciency of 13% was applied on all locations except damp locations C003, C006, C007, and C009-CO12, where an efficiency of 4.9% was used.

2. Net acffvity calculated by adjusting the gross cpm by the ambient bakround.

Material background correction was not applied.

D. SURVEY UNIT INVESTIGATIONS PERFORMED AND RESULTS Based on the direct and scan results, no investigations were required.

FR-2600-0l, Revision 0 Page Sof 33

E. SURVEY UNIT DATA ASSESSMENT An analysis of the direct sample measurement results, including the mean, median, standard deviation, and sample result range is provided in Table 2. None of the 14 direct measurements indicated activity above the DCGL of 9,800 dpm/l 00 cm2 . Measurement activities corrected for ambient background are listed in Table 2. The mean and median activities were less than 50% of the DCGL. The maximum direct sample result with background subtracted was equivalent to 2,857 dpm/100 cm2 . Without subtracting background, all direct measurement results were below the DCGL. The maximum net activity level was 29% of the DCGL.

The ISOCS scan measurements did not detect plant-derived activity in excess of the MDAs.

Therefore, no investigations were required.

The annual dose rate would equate to 0.0004 mrem/year2, using a mean net activity level of 1,632 dpmrl00 cm2.

F. ADDITIONAL DATA EVALUATION Attachment 4 provides additional data evaluation associated with this Survey Unit, including relevant statistical information. Based on survey unit direct measurement data, this attachment provides the Sign Test Summary, Quantile Plot, Histogram, and Retrospective Power Curve.

1. The Sign Test Summary provides an overall summary of design input (Table 1)and resulting calculated values used to determine the required number (N) of direct measurements (per LTP Section 5.4.2). The Sign Test Summary is a separate statistical analysis that also calculates the mean, median, and standard deviation of the direct measurements.

The critical value and the result of the Sign Test are provided in the Sign Test Summary table, as well as a listing of the key release criteria. As shown in the table, key release criteria were satisfied, with one exception. An "Investigate" flag was produced because the direct measurement sigma exceeded the design sigma; however, sufficient power is evident since the survey unit easily passed the Sign Test.

2 This annual dose quivaent is based on LTP Table 6-11 which shows te To Annual Dose from Buried Piping, Conduit, and Cable to be 2.52E.03 mremly. Therefore, the annual dose rate would equate to

( 1,632 Annuwl Dose Rate = 2.52E - 03r 9,80013) 0.004mrem l y FR-2600-01, Revision 0 Page 6 of 33

2. The Quantile Plot was generated from the direct measurement data listed in Table 2 and indicates general symmetry about the median. The data set and plot are consistent with expectations for a Class 3 survey unit. All of the measurements are below the DCGL.

The net activity levels were less than 50°/h of the DCGL.

3. A Histogram Plot was also developed based on the direct measurement activity values.

This plot shows a normal distribution.

4. A Retrospective Power Curve was constructed based on FSS results. The curve shows that this survey unit having a mean residual activity at a small fraction of the DCGL has a high probability ("power") of meeting the release criteria. Thus, it can be concluded that the direct measurement data support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and that the data quality objectives were met.

As mentioned in Section B,.soil or sediment samples were taken in handholes or manholes, where sufficient material existed, in order to provide further confidence that plant-derived materials were not present at levels exceeding the DCOL on the bottom of the vault. Three of the seven samples obtained identified plant-derived nuclide at trace levels (less than 0.47 pCi/g Cs-137).

G. CHANGES IN INITIAL SURVEY UNIT ASSUMPTIONS ON EXTENT OF RESIDUAL ACTIVITY The survey was designed as a Class 3 structure survey area; the FSS results were consistent with that classification. The sample standard deviation is larger than the design sigma, but no additional samples were required since all samples were less than the DCGL.

H. LTP CHANGES SUBSEQUENT TO SURVEY UNIT FSS The ESS of Survey Unit 1 was designed, performed, and evaluated from late 2004 to early 2005. The design was performed to the criteria of the approved LTP Revision 3 Addenda.

There were no subsequent LTP changes with potential impact on the design, conduct, or assessment of the final status survey of Survey Unit 1.

FR-2600-01, Revision 0 Page 7 of 33

1. CONCLUSION The FSS of this survey unit was designed as a Class 3 area. The survey design parameters are presented in Table 1. The required number of direct measurements was determined for the Sign Test in accordance with the LTP. As presented in Table 2, all direct measurements were less than the DCGL of 9,800 dpm/l 00 cm2 .

A Sign Test Summary analysis demonstrated that the Sign Test criteria were satisfied. The direct measurement sigma was determined to be greater than that used for design. However, sufficient samples were taken to pass the Sign Test.

The Retrospective Power Curve shown in Attachment 4 confirmed that sufficient samples were taken to support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and the data quality objectives were met. Attachment 4 also revealed that direct measurement data represented essentially a normal distribution.

The scan survey design for this survey unit was developed in accordance with the LTP Revision 3 Addenda (Reference 1) with significant aspects of the design discussed in Section B and Table 1. ISOCS scans did not identify activity above the scan MDA levels.

Therefore, no investigations were required as a result of the scan process.

It is concluded that FR-2600 Survey Unit I meets the release criteria of IOCFR20.1402 and the State of Maine enhanced criteria.

J. REFERENCES

1. Maine Yankee License Termination Plan, Revision 3, October 15,2002 and Addenda provided by Maine Yankee letter to the NRC, MN-02-061, dated November 26, 2002

2. NRC letter to Maine Yankee, dated February 28, 2003

3. Maine Yankee letter to the NRC, MN-03-049, dated September 11, 2003 (LTP Supplement to LTP Revision 3)

4. Issuance of License Amendment No. 170, NRC letter to Maine Yankee, dated February 18, 2004

5. Maine Yankee Calculation No. EC-003-04, Use of Canberra In Situ Object Counting System (ISOCS) for PSS Surveys

6. Memorandum, Potential Contamination of FR2600 Survey Unit 1 (CR 05-012), dated March 17, 2005 FR-2600-01, Revision 0 Page 8of 33

Attachment 1 Survey Unit Maps FR-2600-01, Revision 0 Page 9 of 33

& A& 8 8~ 8.

o a g a a° g 0

a Q 0

-u

(

8 § (I 8 8 8a a a a a 0 aa t Survey Unit 1 Note: Grid based on Maine State Coordinate System (West Zone) WAD 1927

CD GRAPHIC SCALE:

0 50 100 0(t I U)

Team Maine YankeeDecommissionng ProjedS&Lrvey F.ormeis:110315 Survy TYPO: 0 Cheratertzaton 0 Turnover CM Final Stats Survey I Survey Area Name: Eledtrcal Duotbanks and Manholes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: MH-1 Direct Point COOI

.I-Tap of WMN I. s South Elevation

Decommissioing Team IMaine Yankee DecommsisningProjec Surey FormjRised: I103105 Survey TYP: 0 CharacterIzaion 0 Turnover B Final Status Survey Survey Area Nemo: Elegta Ductbani and Manhoes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: HH-10 (East Road)

Direct Point C002 & C008 O.56m C608 I West Elevation North Elevration

Decommissioning Team IMEdne Yankee DecommissioningProectSiLrvey Form IR~ed: 1nMMe SurveyType: OCharactermizon O Tumover H IStatusSurvey SurvoyAreaName: EkledicDuctbanksandManholes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: MH-2a Direct Point C003 0.13m Top -dofI North Elevation Electrical Ductbank and Manhole Reference Adz 0 // I1' mm /of

Yankee DecommLatoningProjed Suvy Form IRevied: 1itSCI

)

Sufvey TYPO: 0 Charaterzaton 0 Turnover H Final Status Survey ISurvey ker Name EkdtIca Dudbanks and Manhoes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: MH-2a Direct Point C011 Top OfWm _. .

0.s2M Col 1-Co East Elevation

Decommissioning Team _Makze Yankee DecommissiningProjectS Form IRrtsed: 1jiM5 Survey Type: 0 Chracterizaeton 0 Turnover E Fnl ras Sury Survey Ares Name: Eidila-l Ducftnks and Manhoes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: HH-8 Direct Point C004 0.39m West Elevation

\-

Decommissioning Team jM2aine YankeeDecommsslson ngProjectSurvey Form Revis6d:103M5 Survey Type: O Charactefzation C Tumovet IFinal Statusn y SuveyArea Name: Elecutcal Ductbanks and Manholes Final Status Survey FR02600 SUW: Electrical Ductbanks and Manholes: MH-5 Direct Point C005 Bottom

Team MainC YankeeDeconimmLonlngProjedSurpiyForm Revied: W4dOS Guvy Type: O Characotarlatn 0 Turnovr Final tatus Survey ISurmy Area Nwe: Electil Ducftnk and Manholes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: MH-4b Direct Points C006, C007 & C012 O.34m

.- ! - Ii nm'-

_ , ._-~

O.Gbn COS2

,_. I GC012 North Elevation SouthElevation lanhole Reference I .eus 1A

DecommisoningTeam 1MidneYankeeDecommLisionhigProedSurvForm lRe-ved: 1R3i05 SurveyType: OCbaracterlailon O Turnover KFln*8tatus SwVy ] subrvy Area Nane: Eiecricdf Ducibanks and Manholes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: HH-1 1 Direct Point C009 0O.09m

-I . - Top of Wall 121am L -4

'C009 North Elevation

lDecommissioningTeam Mane YankeeDecommnuonIVg Po3JeSwrvy Form Revised: 1i/05 Survey Type: 3 Charactedrization a Turnover M Fhial Status Surey l Survey Area Nam: Elecbical Duotnks and MAnholes Final Status Survey FR02600 SUI: Electrical Ductbanks and Manholes: MH4a Direct Point COIO Top of Wall

-N-1.6 m Ah.

. 0.S l CO1 CI _1O Design Bottom East Elevation

Decommissioning Team lMaineYankeeDecommLtssoningProjectdSweyForm RAevisied lo10s Survey Type: 0 Charatedbtion 0 Turnover E Final Status Su" yI Sumey Area Name: Eledril Ductbanks and Manholes Final Status Survey FR02600 SU1: Electrical Ductbanks and Manholes: HH-12 Direct Point C013 020m

~~~r <T~wa North Elevation

Team lMaIne Yankee De=ooioingPmjeC Suvy Form Revised: 3107/05 Survey TYP_

0 MSurvey Charactertzation 0 Turnover 0 Fol Status Survey kea Nam: Electial Ductbenks and Manholes Final Status Survey FR02600 SUW: Electrical Ductbanks and Manholes: MH-4b Direct Point C014 o.0rm

. - d.

0.E Im p

Ce'4 West Elevation Electrical Ductbank and Manhole QN lhI - /

Decommissioning Team Maine Yankee DecomndssioningProjectSurvey Form lRe-v.ised: 1a03i5 Suvoy Type: 0 Charaterizatlon C Tumover E Final Status 8urvey S Survey Area Narne: Electrical Ducit=_t and Manhoies Final Status Survey FR2600 SU1: Electrical Ductbanks and Manholes Typical Manhole ISOCS Survey Typical Manhole ISOCS CorfIgurason MK-1 throught MS5 FR-2600-01, Revision 0 Page 23 of 33

Maine Yankee - Map ID. FR2600-lm Decommissioning Team Maine YankeeDecommissioningProjectSury Form Revised:1103/05 surveyType: 0 Chaactefration Turnover 19FinalSta Survey IBurvy Area Name: Electrical Ductbanks and Manholes Final Status Survey FR2600 SU 1: Electrical Ductbanks and Manholes Typical Handhole ISOCS Survey iHanhcle ISOCS Confturetionj HH-1 throupi H12 I FR-2600-01, Revision 0 Page 24 of 33

DecmmIssionIngTeam Maine YankeeDecommissioningProjectSurvey Form IRVed:307JO Ourvey Typo: O Charveitzaton ED Turnover 1 Final 8atus Surey iSurveyAeaNane: ElectWaDuctbanksandManholes Final Status Survey FR2600 SU 1: Electrical Ductbanks and Manholes Manhole MHI ISOCS Survey Manhole I ISOCS Condguraon FR-2600-01, Revision 0 Page 25 of 33

Attachment 2 Survey Unit Instrumentation FR-2600-01, Revision 0 Page 26 of33

TABLE 2-1 INSTRUMENT INFORMATION E-600 SIN Probe SIN (type) 1622 149073 (43-68) X 2491 149073 (43-68 ISOCS Detectors (Field Measurements)

Detector No. -_ MDC_l _

7605 67 to 122 (dprn/l 0 cm' 7607 96to 136 (dpm/10cmi)

HPGe Detectors (Laboratory Analysis)

Detector No. MDC FSS_ I 0.04 to 0.06 (pCi/) I FSS2_ 0.04 to 0.05 (pCi/g)

TABLE 2-2 INSTRUMENT SCAN MDC, DCGL, AND INVESTIGATION LEVEL Parameter Instrument: ISOCS Comments Scan MDC 886 dpm/100 cm'2 Cs-137 Design MDC 94 dpmi/10 cm Co-60 Dsg D Gross Beta dpriln00 cm2 DCGL 9,800 dpmIlOO cm 2 for Buried Piping, Conduit and Cable LTP Rev 3,

.__ _Table 6.11 (Reference 1) 4,430 dpmIlOO cm; Cs-137 0 50 eh DCGL (Reference 1)

Investigation Level (Note 1) 470 470 100 cm2 Co-60 _ _ _ _ _ _ _

NOTE 1: Values listed were based on LTP Table 5-3a fractions because several manholes were located adjacent to Class I survey units.

FR-2600-01, Revision 0 Page 27 of 33

Attachment 3 Investigation Table (There were no investigations)

FR-2600-01, Revision 0 Page 28 of 33

Attachment 4 Statistical Data FR-260001, Revision 0 Page 29 of 33

Survey Package FR2600 Unit I Surface Sign Test Summary Survey Package: FR2600 Class 3 Electrical Duct Banks Survey Unit 01 Evaluator G. Madison DCGL,: 9,800 DCGL,,,: 9.800 LBGR: 8,876 Slgma: 308 Type I error. 0.05 Type II error: 0.05 Total Instrument EffcienW.: 13.0% data adjusted for various effs.

Detector Area (cm ): 126 Choosing WN sets material Material Type: NiY background to V Zj': ' 1; 1.-

10 1;.645 _ _ _ _ _ _ _ _ _ _ _ _ _

Sign p: 0.99865 Calculated Relative Shift 3 _

Relative Shift Used: 3.0 Uses 3.0 if Relative Shift >3 N-Value: III N-Value+20%:. 14 Number of Samples:

11 _

Median: .:. 1,41 l Mean:. I,632 Net Sample Standard Deviation: - 803 Total Standard Deviation: 4 83 1SRSS Maximum:j 2.857I Adjusted N Value: 141 S+ Value: ; 141 Critical Value: 1t Sufficient samples collected:' pass___________

Maximum value <DCGLW Pass Median value <DCGLW . PasS Mean value <DCGL; Pass Maximum value <DCGl:., Pass N/A for Class 3 Total Standard Deviation <=Sigma:

investigast SU passes. See Section F Criterla comjjrison results: Pass The survey unit passes all conditions: .investigata SU passes see section F FR-2600-41, Revision 0 Page 30 of 33

FR2600 SU-1 Quantile Plot 3000 N 2500 E * .

00 2000 -

,

Activity (dpm/100 cm2) l

'* _ 0.

i *1.

_ . 1500

. X -Median (dpm/100 OWii 0 cm2) l_

=0 != 1000 - ... .-_I

! < 500 -

0 I 0 25 50 75 100 I Percent

One-Sample T-Test Report PagelDatenTime 2 4111105 6:32:33 AM Database C:AProgram FilesNCSS97AFR2600 SU-1.SO

. Variable C2 Plots Section Histogram of FR-2600. SU-1 Is ActMty (AnmdOO ca2)

FR-2600-01, Revision 0 Page 32 of 33

One-Sample T-Test Power Analysis PagelDateMlime 2 4111/05 6:34:48 AM Chart Section Retrospective Power Curve 1.0,r 0.8+

I.-

. - .1 0) 09 0.44-0.2+

I J.u 1000 3600 50i30 70'00 9000 11600 Survey Unit Mean (dprml100 cm2)

FR-2600-01, Revision 0 Page33 of 33

RA-05-023, Release of Non-ISFSI Site Land - Final Status Survey Final Report No. 9A, Revision 0

Contents

Text

References:

Subject:

1.0 DESCRIPTION

3.0 BACKGROUND

5.0 TECHNICAL EVALUATION

7.0 REFERENCES

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RA-05-023, Release of Non-ISFSI Site Land - Final Status Survey Final Report No. 9A, Revision 0

Text

References:

Subject:

1.0 DESCRIPTION

3.0 BACKGROUND

5.0 TECHNICAL EVALUATION

7.0 REFERENCES

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