ML073111392
ML073111392 | |
Person / Time | |
---|---|
Site: | Plum Brook |
Issue date: | 10/31/2007 |
From: | US National Aeronautics & Space Admin (NASA) |
To: | NRC/RGN-III/DNMS/DB |
References | |
EP-1.63 | |
Download: ML073111392 (12) | |
Text
Survey Unit Release Record Design # EP-1.63 Revision # Original Page 1 of 3 Survey Unit #(s) 1.63
- 1) Embedded Pipe (EP) Survey Unit 1.63 meets the definition of embedded pipe for Plum Brook Reactor Facility (PBRF).
- 2) EP 1.63 is a Class 1, Group 2 survey unit as per the PBRF Final Status Survey Plan (FSSP) and Technical Basis Document (TBD)-06-004.
- 3) Surveys in EP 1.63 were performed using a scintillation detector optimized to measure gamma energies representative of Cs-137. Sample #EP2-5 fiom Survey Request (SR)-13 was referenced for this decision.
- 4) Survey Instructions for this survey unit are incorporated into and performed in accordance with (LAW) the Babcock Services Incorporated @SI)/LVS-002, Work Execution Package (WEP)05-006. Survey instructions described in this Description document constitute "Special Methods" and the survey design used in the acquisition of survey measurements.
- 5) Instrument &ciency determinations are developed in accordance with the BSVLVS-002, WEP 05-006, these determinations are appropriate for the types of radiation involved and the media being surveyed.
FSS Design # EP 1.63 Revision # Original Page 2 of 3 Survey Unit: 1.63 1.1 The subject pipe system is the 6" drain for canal " H .
1.2 EP 1.63 consists of 6" diameter piping that is approximately 10 feet in length.
Survey Design Information 2.1 EP 1.63 was surveyed IAW Procedure #BSI/LVS-002.
2.2 100% of the 6" ID pipe was accessible for survey. The accessible 6" ID pipe was surveyed by static measurement at one foot increments, for a total of 10 survey measurements.
2.3 Surface area for the 6" ID piping is 1,459 cm2for each foot of piping, corresponding to a total 6 ID piping surface area of 14,590 cm2(1.5 mZ) for the entire length of (approximately 10') of 6" piping..
Survey Unit Measurement LocationsData 3.1 Pipe interior radiological survey forms are provided in Attachment 2 of this release record.
Survey Unit Investigations/Results 4.1 None Data Assessment Results 5.1 Data assessment results are provided in the EPIBuried Pipe (BP) Survey Report provided in Attachment 1.
5.2 All measurement results are less than the Derived Concentration Guideline Level (DCGL) for radionuclide specific EP that corresponds to the 1 mrern/yr dose goal established in Table 3-3 of the FSSP.
When implementing the Unity Rule, provided in Section 3.6.3 of the FSSP, and applying the Nuclide Fraction (NF), provided in TBD-06-004, the survey unit that is constituted by EP 1.63 passes FSS.
5.4 Background was not subtracted from the survey measurements and the Elevated Measurement Comparison (EMC) was not employed for this survey unit.
Co-60 is designated as the primary nuclide of concern for Piping Group 2 per Technical Basis Document TBD-06-004, which would typically lead to a survey design based on the direct measurement of Co-60. The field measurements were acquired using a detector windowed for Cs-137 versus Co-60. The survey results documented in this release record are valid as Cs-137 was present in the nuclide distribution for this pipe group in sufficient abundance and the correct nuclide distribution was used to calculate total activity.
>d FSS Design # EP 1.63 Revision # Original Page 3 of 3 Survey Unit: 1.63 L
5.6 Statistical Summary Table Number of Measurements Above DCGL Documentation of evaluations pertaining to compliance with the unrestricted use limit of 25 mremlyr and dose contributions fiom Embedded Pipe and radionuclides contributing 10% in aggregate of the total dose for both structural scenarios and soils.
6.1 A review of the survey results has shown that the dose contribution for EP 1.63 to be less than 1 mredyr. The dose contribution is estimated to be 0.277 mredyr based on the average of the actual gross counts measured.
Attachments Attachment 1 - BSI EPIBP Survey Report Attachment 2 - Pipe Interior Radiological S w e y Form Attachment 3 - DQA Worksheet Attachment 4 -Disc containing RR for EP 1.63 & Spreadsheet
SECTION 7 ATTACHMENT 1
BSI EPIBP SURVEY REPORT DetedorSled # IMGI LVS-11101 TlVlTY VALUES NOT BACKGROUND CORRECTED RP Engineer 1 Date
EP 1.63 6" Pipe TBD 06-004 Group 2 STD DEV 0.202 MAX 0.783 MIN 0.109
SECTION 7 ATTACHMENT 2 t PAGE(S)
i -,--r - - . =,.-
- d BSWSPipeCrawler-002 -'"' '
Revision 5 Pipe Interior Radiological Survey Form Date: 7 - \ 2 - 07 Time:
Pipe ID#: Pipe Diameter: rr -
Access Point Area: , 3, , ( \
Building: Elevation: ' -3s ' System: &or\ w Type of Survey Investigation Characterization Final S w e y ,x Other 4' Gross C06O Cs ,I Detector ID# / Sled ID#
Detector Cal Date: Detector Cal Due Date:
Instrunent: 2350 1 - Instrument ID #: \ (6904'4 Instrument Cal Date: - -
\ 1\ 01 Instrument Cal Due Date: -
\ \\- 0 2 From the Daily Pipe Survey Detector Control Form for the Selected Detector Background Value \ 1 5 6 cpm MDCRstatic \L\ ,I CPm Efficiency Factor for Pipe Diameter .
f) I> 0 0 2 - (fkom detector efficiency determination)
MDCstatic 3143 dpm/ 1 OD cm2 Is the MDCsuticacceptable? No (if no, adjust sample count time and recalculate MDC&,,i,)
Comments: Qas- brl S~N- RQI- 5 1007, bm&,&
Technician Signature @.&
Pipe Interior Radiological Survey Package Page 1 of REFERENCE COPY Attachment 3, Page 1
SECTION 7 ATTACHMENT 3 I PAGE(S)
DQA Check Sheet Design # EP 1.63 Revision # Original Survey Unit # EP I.63 Preliminary Data Review*
Answers to the following questions should be fully documented in the Survey Unit Yes No N/A Release Record
- 1. Have surveys been performed in accordancewith survey instructions in the Survey Design? X
- 2. Is the instrumentation MDC for structure static measurements below the D C G h for Class 1 and 2 X
survey units, or below 0.5 D C G L for Class 3 survey units?
- 3. Is the instrumentation MDC for embeddedlburied piping static measurements below the DCGLW? X
- 4. Was the instrumentation MDC for structure scan measurements, soil scan measurements, and embeddedlburied piping scan measurements below the DCGLw,or, if not, was the need for additional X static measurements or soil samples addressed in the survey design?
- 5. Was the instrumentation MDC for volumetric measurements and smear analysis < 10% DCGLw ? X
- 6. Were the MDCs and assumptions used to develop them appropriate for the instruments and techniques used to perform the survey?
- 7. Were the survey methods used to collect data proper for the types of radiation involved and for the X
media being surveyed?
- 8. Were "Special Methods" for data collection properly applied for the survey unit under review? X
- 9. Is the data set comprised of qualified measurement resub collected in accordancewith the survey X
design, which accurately reflects the radiological status of the facility?
Graphical Data Review
- 1. Has a posting plot been created? X CS-0912 Page 1of 1
SECTION 7 ATTACHMENT 4 1 DISC