ML20133E048

Forwards Comments to Fsv Nuclear Station, Decommissioning Project Final Survey Rept (Volumes 4-11), for Consideration

ML20133E048
Person / Time
Site:	Fort Saint Vrain
Issue date:	01/02/1997
From:	Abelquist E OAK RIDGE ASSOCIATED UNIVERSITIES
To:	Fauver D NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
References
RFTA-96-05, RFTA-96-5, NUDOCS 9701100176
Download: ML20133E048 (8)

Text

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5'a - 37 ORISE OAK RtDGE IN$TITUTE FON SCIE NCF AND E DUCATION January 2,1997 1

Mr. David Fauver '

U.S. Nuclear Regulatory Commission Division of Waste Management - NMSS Two White Flint North T-8F37 11555 Rockville Pike Rockville, MD 20852 l

SUBJECT:

1)OCUMENT REVIEW-FORT ST. VRAIN NUCLEAR STATION DECOMMISSIONING PROJECT FINAL SURVEY REPORT (VOLUMES l 4 TIIROUGII 11), FORT ST. VRAIN, PLATTEVILLE, COLORADO '

(DOCKET NO. 50-267, RFTA NO. 96-05)

Dear Mr. Fauver:

The Environmental Survey and Site Assessment Program (ESSAP) of ORISE has reviewed the i subject documentation and offers the attached comments for your consideration. Specifically, ESSAP reviewed the final survey documentation for adherence to survey procedures, conditions that initiated investigations and how these investigations were resolved, and to ensure survey results satisfied the release criteria.

Please direct any questions or comments to me at (423) 576-3740 or W. L. (Jack) Beck at  !

(423) 576-5031. I Sincerely, Eric W. Abelquist Assistant Program Director Environmental Survey and Site Assessment Program i

EWA:tsf '-

1 J, 0 () '] } I Enclosure /s /

cc: L. Pittiglio, NRC/NMSSrfWFN R. Uleck, NRC/NMSSffWFN 7F27 D. Tiktinsky, NRC/NMSSTFWFN 8A23 W. Beck, ORISE/ESSAP File /672 P O. BOX 117, OAK RIDGE. TENNESSEE 37831 0117 9701100176 970102 ,006 a,ag. Assoc,a,.a univorr. for rh. u.s o.portm.ne of En.<gy PDR ADOCK 05000267 y PDR

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< 1 COMMENTS FORT ST. VRAIN NUCLEAR STATION DECOMMISSIONING PROJECT FINAL SURVEY REPORT (DOCKET NO. 50-267, RFTA NO. 96-05)

GENERAL COMMENT

S In general, the final survey report (Volumes 4 through 11; Survey Groups C through J) adequately describes the survey methodology and instrumentation that was used for the FSV decommissioning project. The site description, survey unit operational history, and decommissioning activities provide detailed information on the radiological status of the site. As noted during the review of Volumes 1 through 4, the results of the survey unit investigations performed during the final survey were generally complete and provided adequate resolution. Specifically, the results of beta scans that identified elevated direct radiation provided clear explanation of how these hot spots were addressed--e.g., performing investigation measurements to confirm activity, decisions to remediate, ,

and results of remediation surveys.

While the licensee commonly performed investigations to evaluate anomalous data, and most investigation conclusions regarding survey unit compliance with release criteria were clearly stated, there were some exceptions. For example, there were numerous instances were an investigation survey failed to confirm areas of elevated residual radioactivity identified during an initial survey, I and that did not provide an explanation for the vanishing activity. That is, the documentation of investigation surveys performed to confirm initials findings of elevated activity often left the I impression that the initial activity was not there. For example, in C0039, the initial total surface activity was 6,659 dpm/100 cm2 , and the removable activity was 175 dpm/100 cm 2 The l investigation section merely stated that the initial activity could not be confirmed and therefore it was not reported. This was also identified in C0047 and C0043, C0045, D4500, D7300, F0032, F0039, F0041, F0042, F0069, F0077, F0084, F0086, F0099, F0120, F0143 (EZ001), F0173, F0186, and F0188. It is recommended that un explanation be provided in these cases-it should be clarified that the initial activity did exist, but that the smear may have removed it. Examples of explanations are provided in F0071, F0113 and F0146.

As identified during the review of the initial FSV final report submittal, the frequency of sampling for bard-to-detect-nuclides (HTDN) in suspect affected areas appears to be very minimal, especially for Fe-55, which comprises the majority of the residual radioactivity at the FSV facility-it was ESS AP's understanding that some frequency of sampling for HTDN would be performed in affected areas, yet it appears that only a few survey areas discuss HTDN. For example, during the PCRV cutting operations a slurry leaked into the vaults in F0095 and F0097, and water spilled in survey unit F0002 from tendon tubes. However, no assessment of H-3 or Fe-55 was performed in this survey unit.

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j In the statistical summary section for suspect affected survey units, most of the time the test of 2

percent of samples exceeding 3,000 dpm/100 cm is compared to 10%, while in other case it is compared to 25%. Please provide an explanation for the use of these different values.

Some of the Group G survey areas do not include introductory text that clarifies whether the  !

appropriate limits were 4,000 or 100,000 dpm/100 cm2 . G7201 is an example of a survey area that - i l . clearly states up-front whether or not the pipe required grouting, and therefore, that the 100,000

] dpm/100 cm2 guideline applied.

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l j SPECIFIC COMMENTS f 1. Volume 4, C0018 - Approximately 70% of the total surface activity levels in survey unit AZ001CZ are negative. It appears that an improper medium background has been subtracted to bias these measurements low. Other survey units with unexplained negatively biased total surface activity include C0041 (BZ001), F0032 (WZ001BZ and AZ001CZ), and F0069.

2. Volume 4, C0026, p. 7 - Scans performed during the 10% verification survey did identify an area of elevated direct radiation-this should be reflected in the Survey Design section.

3. Volume 4, C0026, p. 8 - Investigation #4 is incorrectly dated 07/07/97.

4. Volume 4, C0026, p. 59 - There appears to be an incorrect calculation; 451.7 -

2 cpm / detector area equals 1,628 dpm/100 cm -not 1,544 dpm/100 cm , 2

5. Volume 4, C0029, p. 54 - Results of beta scanning were not included under the Survey Design section.

6. Volume 4, C0034, p. 8 " Spectrums" should be spectra. Also noted on page 11 of F0155.

7. Volume 4, C0035, p.2 - It was reported that no affected systems resided within this survey area, yet portions of System 75 within the survey unit required remediation.

Please provide an explanation for this apparent discrepancy.

8. Volume 4, C0037 - It appears that this survey unit may be improperly classified as unaffected. The 10% test for total surface activity was right at 10%,60% of the total surface activity results exceeded the critical level, and 28 of 30 smears also exceeded the critical level. Based on these results, it is recommended that this survey unit be reclassified and a 100% scan performed.

9. Volume 4, C0041, p.133 - The removable activity at SML 595 (92.9 dpm/100 cm2 )

generated during the investigation does not appear to have been plotted.

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10. Volume 4, C0064, p.2 - This survey package should be described as QC verification of survey package C0042, not of C0064.

I 1. Volume 5, D4100, p. 5 - Typo: Should be Th-234 and Pb-212, not Th-232. Same typo on pages 7 and 8 of G4600.

12. Volume 5, D4200 - An investigation was performed within this unaffected survey unit to address two total surface activity results that were approximately 5,000 dpm/100 cm2 ,

These measurements were corrected for natural radioactivity, based on gamma -

spectroscopy analyses. While this investigation adequately resolved any questions relating to these two neasurements, it appears that this natural background was not fully accounted for in the MDA determination. It is therefore recommended that the MDA of the total surface activity measurement be evaluated, considering the increased natural activity component, to determine if the MDA for measurements in this survey unit (and other similar survey units) satisfies the 25% of guideline criterion for unaffected areas.

13. Volume 5, D4402 - The appropriate guideline for scale / sediment is not clearly stated in this survey unit.

14. Volume 5, D4500, p. 7 - Appears to be a typo: "...therefore, not greater than..."

15. Volume 5, D7300 - The beta scan results are not stated in the survey design section.

16. Volume 5, D7501, p.19 - A scale sample from location 74-1 exhibited 6.25 pCi/g of Co-60, however, the total surface activity result at the same location is -1,337.5 dpm/100 cm 2. Please provide an explanation for this apparent discrepancy.

17. Volume 5, D7502 - The beta scan result was stated as "no areas of significantly elevated activity were identified." Please provide an explanation for "significantly elevated".

18. Volume 6, Group E, Table 3.1 - It appears that the units in the exposure rate and soil columns are incorrect.

19. Volume 6, E0001, p. 2 - It appears that there is a discrepancy; the text states that the survey unit is suspect affected, while the table box states it is non-suspect affected.

20. Volume 6, E0002 - SMLs 95 and 101 exhibit specific guideline values (SGLVs) of 2.90 and 2.94, both very close to the maximum limit of 3. Was there any consideration of the uncertainty in these values, specifically in terms of demonstrating compliance with the maximum value with some degree of confidence?

21. Volume 6, E0003 - What were the guideline values and units for water samples? The comments above each data table state net concentration reported in pCi/g. The appropriate units should be pCi/L or other similar designation.

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22. Volume 6, E0010, p. 6 - Gamma surface scans were not indicated in the survey design

.section-were they performed? Similarly, were gamma scans performed in E0011 and E0012? i I

23. Volume 6, E0010, p.8 - An "Affected, Class 3 survey unit" is introduced in this survey l area. Please provide a description of this generic survey unit type.  !

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24. Volume 6, E0013 - There is confusion concerning the statistical summary tests; l sometimes an action level of 0.75 is used, and at other times 0.25.

25. Volume 6, E0014 - This survey unit included 42 subsurface soil samples. Itis

. recommended that this condition be described at the beginning of the survey package. j l

26. Volume 6, E0014 - SML 39 exhibits subsurface contamination. How was a determination made concerning the depth of contamination? l

27. Volume 7, F0043 - Although it is recognized that an investigation was performed to ,

address the issue, there remains a negative bias in survey unit WZ002BZ on the order of I 88% negative surface activity levels.  ;

28. Volume 7, F0053, p. 2 - Add lower walls to the " classification / surface category" for 3 survey unit BZ001. l l

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29. Volume 7, F0191 - The QC survey for F0074 identified an elevated area of '

approximately 17,000 dpm/100 cm2on a scaffolding handrail. Is there any indication as to why the initial survey in F0074 did not identify this elevated area? l

30. Volume 7, F0075 - One value for removable activity is reported as -108 dpm/100 cm2, Please explain this extremely negative result.

31. Volume 7, F0093, p.8 - Typo: Investigation No. 2, not No.1, was performed on 5/31/96.

32. Volume 7, F0018 - There appears to be a discrepancy in protocol. An initial measurement (17,902 dpm/100 cm 2) was remediated without an investigation survey j performed. In most similar situations an investigation survey was performed to confirm the elevated activity, but it does not appear to have been performed in this case. This discrepancy was also identified in F0024, F0062, F0065, and F0066.

33. Volume 7, F0019 - It appears that removable surface activity results are provided twice for survey unit BZ001BZ.

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34. Volume 7, F0022 - The results of the remediation survey were not reported in the  ;

investigation section. Typically, the remediation survey results are either provided or a .i statement is made that the remediation survey was successful. This was also identified in F0024, F0148.

35. Volume 7, F0100 - There appears to be a discrepancy in protocol. Initial measurements of two areas identified by beta scans exhibited 2,389 and 2,032 dpm/100 cm2 . These l measurements were investigated, when in most cases measurements that did not exceed . l action levels were simply stated as such.

36. Volume 7, F0119, p. 7 - It appears that there should be two areas of elevated activity identified by scans reported in the survey design section.

37. Volume 7, F0194 - The QC survey for F01.45 identified a mean total surface activity 2

level nearly twice that in F0145 (507 versus 265 dpm/100 cm ). What was the criterion used to evaluate the results of the QC sutvey when comparing to the initial final survey?

38. Volume 7, F0156 and F0174 - It is unclear in the investigation section as to which areas of elevated direct radiation were identified by beta scans.

39. Volume 7, F0161 and F0162, p.3 - Typo: Beta, not " bete" and delete "an" preceding "areu", if plural is appropriate. .

40. Volume 7, F0167 - The mean total surface activity level was over 1,000 dpm/100 cm2 in this survey unit It does not appear that a medium background was used to correct the gross measurement data.

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41. Volume 7, F0168, p.3 - Bays were incorrectly referenced and should be referenced as

. Bays 22 to 24.

42. Volume 7, F0171 - It appears that only one area of elevated activity was identified by beta scans; the other area appears to be located at a systematic location.

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43. Volume 7, F0178 - Approximately 96% (67 of 70 measurements) of the total surface activity levels for download 1100-3 are negative.

44. Volume 7, F0180 - It is unclear if a scan was performed during the final status survey;

p. 3 states that the characterization scan was accepted as scan survey of record, however, the report implies that another scan was performed during the final status survey.

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i 45. Volume 7, F0182, p. 6 - There appears to be a discrepancy in the number of total surface activity measurements reported; it appears that the 30 measurements from the remediation survey have not been added to the total. Also, the results of the remediation survey were not stated in the investigation section. A similar discrepancy was noted in 1 F0183.

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46. Volume 7, F0186 - It is unclear if characterization scans were used as the scan survey of l record; specifically, the report does not state that the characterization scans meet the quality requirements.

s 47. Volume 8, G1100 - It is not clear how the 1 m2 average requirement for surface activity was demonstrated. Specifically, what was the average for location #57 Also, p. 7 l appears to conflict with p.5 as to the number measurements performed at location #5.

l j 48. Volume 8, G6101, p. 4 - It is agreed that the application of a masslinn smear is a

{ qualitative technique and therefore, it is questionable to report results based on this 1

technique. The collection efficiency obtained by passing a masslinn smear through a

! pipe is extremely variable, and may be much less than 100%. Therefore, it is

recommended that the only conclusions that should be drawn from positive l contamination on a masslinn smear is that removable contamination does exist within the

! pipe.

49. Volume 9, H0001 - Page 60 was missing from report.

l I 50. Volume 9, H0002, p.10 - Under results of beta scans, "were" identified should be "was" identified.

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51. Volume 9, H0003 - Pages were misnumbered; p. 32 follows p. 25.

52. Volume 9, H0004 - The survey unit investigations are difficult to interpret-Investigation #1 in WZ001 discusses elevated activity identified in WZ002-and correlate to information contained in the survey design sections.

53. Volume 9, H0009, p. 49 - The report incorrectly states that there were no investigations performed.

54. Volume 9, H0005, p. 6 - The report states that the total surface activity (TSA) levels were biased high. The background levels were reviewed and determined to be appropriate. Is there some other factor that accounts for TSA levels to be biased high or are the TSA levels reported indicative of true residual activity? Furthermore, TSA levels for H0006 are approximately the same as for H0005, yet there is no note that TSA levels were biased high.

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55. Volume 9, H0006 - The results of bta scans on p. 53 indicate that 11 elevated areas were I identified, however, on page 12 the report states that only 4 locations (SML 127 to 130) ,

were identified during the scan survey.

i ll 56. Volume 9, H0600, p.27 - Field background for location 21-2 appears high relative to j l adjacent locations.

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57. Volume 10, I0002, p.8 - Typo: " effected" should be "affected". Also on p. 7 of10026.

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58. Volume 10,10004, p.8 - The report states that water activity reported in pCi/g. It appears that the units are incorrect.

59. Volume 10, I0024, p.3 - The report states that no licensed material was identified by soil analyses. However, soil results for locations 22 and 26 both contained Co-60 concentrations at levels exceeding the minimum detectable activity (MDA).

60. Volmne 10, I0025, p.3 - The survey are conclusion states that total and removable surface activity levels meet release criteria, however, these measurements were not taken (this survey unit consisted of soil samples).

61. Volume 10, I0025, p.6 - The report states that nine elevated areas were identified by the gamma scan. A summary of soil sample results corresponding to these elevated locations was not provided.

62. Volume 10, I0025 -It appears that the characterization soil sample results were used as the final survey record. Were these soil data evaluated to determine if data quality requirements were met?

63. Volume 10,17900 - Page 2 does not state the survey unit cir.ssification (affected).

64. Volume 11, J0001, p.6 - Typo: Should be " possess".

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