ML081610156
| ML081610156 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 04/03/2008 |
| From: | Tallman D Sacramento Municipal Utility District (SMUD) |
| To: | NRC/FSME |
| References | |
| F8000071 | |
| Download: ML081610156 (22) | |
Text
Rancho Seco Final Status Survey Summary Report April 2, 2008 Western Industrial Area Survey Unit F8000071 Prepared By: Dan A. Tallman te: April 3, 2008 FSS En*n eviewed By:
Date:
Lead S Engineer R
Approved Date:_ __/___
Radiological
FINAL STATUS SURVEY
SUMMARY
REPORT Survey Unit:
F8000071, Western Industrial Area Survey Unit
Description:
Operating History: This area covers the majority of Industrial Area soils exclusive of the building footprints and rail line in this area. Operating records and the HSA document no specific release of radioactivity in these survey areas however this area does border known contaminated areas. The HSA recorded no specific unplanned release events.
Site Characterization: Soil and sediment samples were collected and analyzed for the presence of plant-derived radionuclides. Cs-137 was the only detected nuclide of plant origin with a mean activity level of 0.062 pCi/g and a maximum value of 0.299 pCi/g.
(Site background levels of Cs-137 have been determined to be approximately 0.3 12 pCi/g.) As described in section 2 of the LTP, the area was evaluated using DSIP-0020 and was designated as Class 3.
Survey Unit Design Information:
The Survey Unit Design Parameters are presented in Table I below. The survey unit and measurement locations are depicted on the maps in Attachment 1.. Direct measurement locations were randomly determined and 5628 m2 were'scanned for approximately 6%
coverage. Soil samples were collected at each direct measurement location and analyzed by HPGe detector. The instrumentation used for the survey along with the. MDC values are listed in Tables 2-1 and 2-2 in Attachment 2.
Page 2 of 7 FSS Summary Report F8000071
Table 1. Survey Unit Design Parameters Survey Design Parameter Value Comment Survey Area:
F800 Western Industrial Area Survey Unit:
0071 Open Land Area Class:
3 LTP Table 5-4 SU Area (m 2):
88190 Evaluator:
D.A.Tallman DCGL Cs137 surrogate (pCi/g):
51.2 Area Factor:
N/A Class 3 Design DCGLemc (pCi/g):
N/A Class 3 LBGR (pCi/g):
25.6 Default = 50% DCGL Design Sigma (pCi/g):
0.034 DTBD-06-001, Table 5-4D Type I Error:
0.05 Type II Error:
0.05 Nuclide:
Cs137 Sample Area (m2):
N/A Class 3 Total Area Scanned (m2):
5628 Scan Coverage (%):
6.4%
Class 3 Zi. :
1.645 Zl-P :
1.645 Sign P:
0.99865 Calculated Relative Shift:
752.9 Relative Shift Used:
3 Uses 3.0 if Rel Shift >3 N-Value:
11 Design N-Value + 20%:
14 NUREG-1575 Table 5-5 Grid Spacing L:
N/A Class 3 Page 3 of 7 FSS Summary Report F8000071
Survey Results:
A total of 14 direct measurements were made in F8000071. The results including mean, median, standard deviation and range are shown in Table 2. All of the direct measurements were less than the DCGL. None of the scan measurements indicated areas of elevated activity. Soil samples were counted to the MDC shown in Table 2-1 of.
Table 2. Direct Measurement Results (all activity values in pCi/g)
Measurement ID Cs137 MDA Cs137 Activity Uncertainty Mean:
6.3 6E-02 Median:~
6.64E-02 Standard Deviation 'j:
1.50E-02
- !*}
Range:
3.65E-02 to 9.02E-02 F8000071SOOO1SS 4.75E-02
< 4.75E-02 F8000071SO002SS 6.56E-02
< 6.56E-02 F8000071SO003SS 6.83E-02
< 6.83E-02 F8000071SO004SS 6.75E-02
< 6.75E-02 F8000071S0005SS 9.02E-02
< 9.02E-02 F8000071S0006SS 5.44E-02
< 5.44E-02 F8000071S0007SS 5.85E-02
<'5.85E-02 F8000071S0008SS 5.94E-02 8.83E-02 4.89E-02 F8000071S0009SS 4.51E-02
< 4.51E-02 F8000071S0010SS 3.65E-02
< 3.65E-02 F8000071S0011SS 6.00E-02
< 6.00E-02 F8000071S0012SS 6.93E-02
< 6.93E-02 F8000071S0013SS 6.72E-02
< 6.72E-02 F8000071S0014SS 7.23E-02
< 7.23E-02 Page 4 of 7 FSS Summary Report F8000071
Survey Unit Data Assessment:
The survey design required 14 direct measurements for the Sign Test. The critical value and the results of the Sign Test are presented in Table 3. The sample mean and median values were less than the DCGL. The sample standard deviation was less than the design standard deviation so no additional samples were required.
Page 5 of 7 FSS Summary Report F8000071
Table 3. Data Assessment Results Survey Results Parameter Value Comment Actual Direct Measurements (N):
14 Median (pCi/g):
6.64E-02 Mean (pCi/g):
6.36E-02 Standard Deviation (pci/g):
1.50E-02 Maximum (pCi/g):
9.02E-02 Sign Test Final N Value:
14 S+ Value:
14 Critical Value:
10 Sufficient Samples Collected:
Yes Maximum Value < DCGL:
Yes Median Value < DCGL:
Yes Mean Value < DCGL:
Yes Maximum Value < DCGLemc:
N/A Class 3 Standard Deviation <= Sigma:
Yes Pass the Sign Test?
Yes Reject the Null Hypothesis?
Yes The survey unit passes all conditions?]
Yes Page 6 of 7 FSS Summary Report F8000071
Survey Unit Investigations and Results:
No investigations were required for either direct or scan measurements and no investigation results are reported.
ALARA Statement:
As stated in Chapter 4 of the LTP, as long as the residual activity within the survey unit is less than the DCGL (i.e. the survey unit average activity is less than the DCGL and the EMC criterion has been met), the ALARA criterion has been met.
Changes in Initial Survey Unit Assumptions:
The survey unit was designed as a Class 3 land survey and the sample results are consistent with that classification. The variability of the survey results was less than the characterization data used for survey design. No potential areas of elevated activity were detected..
==
Conclusion:==
The FSS of this survey unit was properly designed as a Class 3 survey based on Table 5-4 of the LTP. The required number of direct measurements was made and the scan coverage met the requirement of Table 5-6 of the LTP. All of the direct measurements were less than the DCGL. No investigations were required 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.
It is concluded that survey unit F8000071 meets the release criteria of 10CFR20.1402.
Page 7 of 7 FSS Summary Report F8000071 Maps April 2, 2008 Survey Unit F8000071
t'J 0
00 6813088E 1889258N
\\
RIGHT HATCHED AREAS ARE NOT INCU.IDED IN THIS SURVEY UNIT KEY PLAN
- /
~1 X--6812858E
.1 *88~65N 6812776E 185859IN 6812497E 1889620N 81765 SM SOIL I
6812703E 1885323N OOi 00 0 10 20 30 40 50 SCALE.
METERS ON, SACRAMENTO MUNICIPAL UTILFIY DISTRICT WEST INDUSTRIAL AREA LAND AREA 800007
-o 0
00 00 oZ
>D 0
0.20 30 40 50 SCALE METER.
SS:MU13 SACRAMENTO MUNICIPAL UTILiTY DISTRICT WESTERN IA PAVED/LAND AREAS DIRECT MEASUREMENT/SOIL SAMPLE LOCATIONS 8000071-MI
CD
-41 0
00 00 c:)
(* S:MUD SACRAMENTO MUNICIPAL UTILITY DISTRICT WESTERN IA PAVED/LAND AREAS GAMMA SCAN LOCATIONS 8000071 -M2 L: 8000007 SHT 1 OF 5 RC RAI
0 00 D
MATCH LINE SHEET 3 OF 5 SACRAMENTO MUNICIPAL UTILITY DISTRICT WESTERN IA PAVED/LAND AREAS GAMMA SCAN LOCATIONS 8.000071-M2 FILE: 800007 SHT 2 OF 5 RC RAY 0
5 10 15 20 SCALE METERS MOND i
C'D 0
00 0328
.1/
- 029,
/
0732
/
071>
08*
MAI(..
LINE. SHEET 2 OF 5
/
/
\\
I--
~(02Y /
/
te0 2
1 o9:
///
/1" 1ý 07.
ID6 61, 7,
/
/
/
1k.
/
V'-
0179 C8)
I>
/V/*LI I,/-
/
\\
0ri 00 0
0 0
MATCH LINE SHEET 4 OF 5 I#
/ J 0
5 10 15 20 SCALE METERS
( IND
- )" smum SACRAMENTO MUNICIPAL UTILITY DISTRICT WESTERN IA PAVED/LAND AREAS GAMMA SCAN LOCATIONS 8000071-M2 LE: 800007 SHT 3 OF 55 RC RAY i, -
¢t-* t"] I'*1 r*
Fl
,MOND.
"--a 0
00 00 C)
C)*L r2 v-'
4AT~HLN.E/ SHEET: 3 OF 5
\\
//
A/V A
/
/'
142 15145 (0i), 08 1709 CID4 /13 I 3 MATCH LINE SHEET 5 OF 5 0
5 1215 20 SCALE METERS SmU*
SACRAMENTO MUNICIPAL UTIUT-Y DISTRICT WESTERN IA PAVED/LAND AREAS GAMMA SCAN LOCATIONS 8000071-M2 FILE: R00007 SHT 4 OF 5 RO RAYMOND
00 000
ý-t 00 0
0 C)
C) i/
I WESTERN IA PAVED/LAND AREAS CONFIRMATORY GAMMA SCAN LOCATIONS 80000t1 -M2
-E: 800007 SHT 5 OF 5 RO CRA) o 10 15 go SCALE METERS Instrumentation April 2, 2008 Survey Unit F8000071
Table 2-1. Survey Unit Instrumentation Detector Detector Detector Serial Instrument Model No.
MDC No.No.
HPGe N/A 9987008 Soil - 0.0723 pCi/g Cs-137 Soil - 0.0732 pCi/g Co-6O HSoil
- 0.0638 pCi/g Co-60 Soil - 0.344 pCi/g Cs-137 ISOCS N/A 2983947 Soil - 0.249 pCi/g Co-60 Asphalt -0.727 pCi/g Cs-137 Asphalt - 0.479 pCi/g Co-60 Table 2-2. Investigation Criteria and DCGL Instrument Parameter Value
- Soil - 23 pCi/g Cs-137 Soil - 5 pCi/g Co-GO ISOCS Investigation Criteria - Scan Sphl - 5pCi/g Co-60 Asphalt - 23 pCi/g Cs-13 7 Asphalt - 5 pCi/g Co-60 All DCGLw.
51.2 Cs-137 1 D12.6 Co-60 Page 2 of 2 Att. 2 Instrumentation F8000071 Investigation April 2, 2008 Survey Unit F8000071 (none required)
Data Assessment April 2, 2008 Survey Unit F8000071
IQ 0
F8000071 Quantile Plot Cs137 DCGL 51.2 pClg 0.090 0.080,~
0.0700.066 60.060
>, 0.050 nc cn 0.040 00 0.020'~
0.01 0..
0.000 0
20 40 60 80 100 Percentile Actfiiý* -
Median ---
- 75th Percentile ----
50th Percentile
~I1 0o 0
0
0 Ci2 (12 F8000071 Scatter Plot Cs137 DCGL = 51.2 pCiIg 1.20E-01
-109 1.001E-01 0
o S8.OOE,.02 6,00E -*
D.6 00 o
o 4.00E-02 o
2.00E -
. )D1e O.OOE+OO Measurement Locations o
Activity -
Average
"+3StDev"....-
3SiDer 00I 00 C)
0T 00 C)j F8000071 Frequency Plot Cs1 37 DCGL = 51.2 pCi/g 7
6
- 5 d1) 4 3
22
-_Q 0.1 0
r53-Co A4~.
cb.
Bins - Upper End Value (pCi/g)