ML081580576

Final Status Survey Summary Report, April 3, 2008, North Retention Basin, Survey Unit F8480011

ML081580576
Person / Time
Site:	Rancho Seco
Issue date:	04/03/2008
From:	Sacramento Municipal Utility District (SMUD)
To:	NRC/FSME
References
MPC&D 08-032
Download: ML081580576 (26)

Text

Rancho Seco Final Status Survey Summary Report April 3, 2008 North Retention Basin Survey Unit F8480011 Prepared B*

Date:

FSSnger Reviewed By:

Date:A/ 4 //

f Lead FSS Engineer Approved By:

Date:

Dismantlement Su erintendent, Radiological

FINAL STATUS SURVEY

SUMMARY

REPORT Survey Unit:

F848001 1, North Retention Basin Survey Unit

Description:

Operating History: This area is located at the southwest corner of the site. The area surrounds the structures that were used for containment and final treatment of liquid effluents prior to their release from the site. Contaminated resin was reported to have been found in the basins. Operating records and the HSA document occurrences of radioactive material with the potential for a release of radioactivity associated with this survey area. Records confirmed the presence of radioactive material within the area and basin sediment/soil contamination levels up to -290 pCi/g. In addition, soil contamination levels up to -5 pCi/g prior to some decontamination activities.

Site Characterization: Soil samples were collected and showed Cs-137 at mean activity levels of 0.086 pCi/g and a maximum activity of 0.196 pCi/g. Based on the classification procedure (DSIP-0020) and previously reported levels of gross activity, the area was determined to be Class 1.

HSA Events: LER-8812.

Survey Unit Design Information:

The Survey Unit Design Parameters are presented in Table 1 below. The survey unit and measurement locations are depicted on the maps in Attachment 1. Direct measurement locations were determined using a random-start, fixed grid pattern and 1432 m2 were scanned for approximately 10 0% 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 8 FSS Summary Report F8480011

Table 1. Survey Unit Design Parameters Survey Design Parameter Value Comment Survey Area:

F848 North Retention Basin Survey Unit:

0011 Open Land Area Class:

1 LTP Table 5-4 SU Area (m2):

1432 Evaluator:

Gary Frank DCGL for Cs-137 surrogate (pci/g):

52.6 DCGL for Co-60 (pCi/g):

12.6 Area Factor:

1.2 Class 1 Design DCGLemc ýpci/g):

64.6 Class 1 LBGR (pCi/g):

25.6 Adjusted Design Sigma (pCi/g):

0.49 DTBD-06-001, Table 5-4A or B Type I Error:

0.05 Type II Error:

0.05 Sample Area (m2):

102.3 Class 1 Total Area Scanned (m2):

1432 Scan Coverage (%):

100%

Class 1 Zi-. :1.645 Zj-P :1.645 Sign P:

0.99865 Calculated Relative Shift:

55.1 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:

10.1 Class 1 Page 3 of 8 FSS Summary Report F8480011

Survey Results:

A total of 29 direct measurements were made in F84800 11. The results are shown in Table 2-1. Statistical data including the mean, median, and standard deviation are shown in Table 2-2. All of the direct measurements were less than Unity. None of the scan measurements indicated areas of elevated activity. Soil samples were counted to the MDCs shown in Table 2-1 of Attachment 2.

In situ gamma spectroscopy (ISOCS) was performed on the soil on the floor of the basin.

Forty-three ISOCS scans were made and the maximum as left value for Cs-137 was 3.28 pCi/g and for Co-60 0.275 pCi/g. In addition, 117 scan measurements were performed with the 2350-1 and 44-10 detector to look for discrete particles in the basin floor, walls, and trench which resulted in 100% coverage. Seventy-one of the particle scans had count rates greater then the investigation criterion of 8200 c/m. Fifteen scan grids (Grid 1, 3, 13, 29, 30, 47, 67, 76, 79, 90, 91, 93, 95, 115, and 116) showed initial soil activity greater than the DCGLw and were remediated below the DCGLW. Grids exceeding the investigation criteria were sampled and evaluated as shown in Table 3-1. Selected grids greater than the DCGLw (Grids 1, 29, and 30) were sampled at depth to ensure there was no downward migration of activity, Page 4 of 8 FSS Summary Report F8480011

Table 2-1. Direct Measurement Results (all activity values in pCi/g)

.*>Cs 137 Co6O Sample ID MDA Activity Uncertainty Unity MDA Activity Uncertainty Value Unity

-Value MD ciiy Ucrany Value Total F8480011SOOO1SS 4.74E-02

<4.74E-02 0.0009 3.98E-02

<3.98E-02 0.0032 0.0041 F8480011S0002SS 4.02E-02

<4.02E-02 0.0008 3.OOE-02

<3.00E-02 0.0024 0.0031 F8480011S0003SS 9.16E-02 3.51E00 1.82E-01 0.0668 6.26E-02 1.41E-01 3.91E-02 0.0112 0.078 F8480011S0004SS 7.83E-02 1.34E-01 5.63E-02 0.0025 6.74E-02

<6.74E-02 0.0053 0.0079 F8480011S0006SS 6.75E-02 1.33E00 1.08E-01 0.0253 8.48E-02

<8.48E-02 0.0067 0.0321 F8480011S0007SS 5.18E-02 1.01E-01 4.04E-02 0.0019 3.79E-02

<3.79E-02 0.003 0.0049 F8480011S0008SS 7.91E-02 2.21E00

.1.47E-01 0.042 1.09E-01

<1.09E-01 0.0087 0.0506 F8480011S0009SS 5.94E-02

• 1.60E00 1.14E-01 0.0305 6.13E-02

<6.13E-02 0.0049 0.0354 F8480011SOOlOSS 6.86E-02 1.98E00 1.40E-01 0.0377 5.64E-02 1.80E-01 4.01E-02 0.0143 0.052 F8480011SO011SS 7.35E-02 2.20E00 1.45E-01 0.0418 5.39E-02 1.81E-01 4.06E-02 0.0143 0.0562 F8480011S0012SS 6.11E-02 1.37E00 1.16E-01 0.026 8.30E-02

<8.30E-02 0.0066 0.0326 F8480011S0013SS 8.62E-02 9.02E00 2.88E-01 0.1714 3.93E-02 1.71E-01 3.75E-02 0.0136 0.185 F8480011S0014SS 4.74E-02 9.15E-02 3.77E-02 0.0017 5.43E-02

<5.43E-02 0.0043 0.006 F8480011S0015SS 9.32E-02 9.29E00 2.88E-01 0.1767 5.27E-02 1.98E-01 4.16E-02 0.0157 0.1924 F8480011S0016SS 7.02E-02 2.54E00 1.58E-01 0.0483 5.64E-02 1.68E-01 3.92E-02 0.0133 0.0617 F8480011S0017SS 8.91E-02 3.58E00 1.87E-01 0.0681 1.24E-01

<1.24E-01 0.0098 0.0779 F8480011SO018SS 7.36E-02 1.56E00 1.26E-01 0.0296 8.06E-02

<8.06E-02 0.0064 0.036, F8480011S0018SS 7.36E-02 1.56E00 1.26E-01 0.0296 8.06E-02

<8.06E-02 0.0064 0.036 F8480011S0019SS 8.18E-02 4.15E00 1.99E-01 0.079 5.25E-02 1.10E-01 3.35E-02 0.0088 0.0878 F8480011S0020SS 5.44E-02 3.17E-01 5.83E-02 0.006 5.79E-02

<5.79E-02 0.0046 0.0106 F8480011S0021SS 7.07E-02 1.47E-01 5.32E-02 0.0028 3.97E-02

<3.97E-02 0.0032 0.006 F8480011S0022SS 6.89E-02 1.36E00 1.26E-01 0.0258 9.54E-02

<9.54E-02 0.0076 0.0334 F8480011S0023SS 8.72E-02 3.45E00 1.81E-01 0.0655 4.09E-02 1.88E-01 4.12E-02 0.0149 0.0805 F8480011S0024SS 6.75E-02 1.52E00 1.28E-01 0.0288 9.85E-02

<9.85E-02 0.0078 0.0366 F8480011S0025SS 7.17E-02

<7.17E-02 4.58E-02 0.0014 6.11E-02

<6.1 tE-02 0.0048 0.0062 F8480011S0026SS 6.01E-02 4.46E-01 7.09E-02 0.0085 8.68E-02

<8.68E-02 0.0069 0.0154 F8480011S0027SS 5.79E-02

<5.79E-02 0.0011 5.39E-02

<5.39E-02 0.0043 0.0054 F8480011S0028SS 7.47E-02

<7.47E-02 0.0014 6.19E-02

<6.19E-02 0.0049 0.0063 F8480011S0029SS 7.56E-02

<7.56E-02 0.0014 5.87E-02

<5.87E-02 0.0047 0.0061 Page 5 of 8 FSS Summary Report F8480011

Table 2-2. Direct Measurements Results Summary Cs 137 Co6O Activity Activity Cs137 Unity Co60 Unity Unity Total DCGLw 52.6 12.6 1

~j7$2 4

Mean 1.86E00 9.67E-02 0.0353 0.0077 0.043 Median 1.37E00 8.30E-02 0.026 0.0066 0.0334 Standard 2.37E00 5.1OE-02 0.0451 0.004 0.0483 Deviation Cs137 Activity Range (pCi!9) 4.02E-02 to 9.29E00 Co60 Activity Range (pCi/g) 3.OOE-02 to 1.98E-01 Cs137 Unity Range 0.0008 to 0.1767 Co60 Unity Range 0.0024 to 0.0157 Total Unity Range 0.0031 to 0.1924 Sample Count 29 Survey Unit Data Assessment:

The survey design required 29 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 greater than the design standard deviation, but no additional samples were required.

Page 6 of 8 FSS Summary Report F8480011

Table 3. Data Assessment Results Survey Results Parameter Value Comment Actual Direct Measurements (N):

29 Median (unity):

0.033 Mean (Unity):

0.043 Direct Measurement Std Deviation (Unity):

0.048 Maximum (Unity):

0.192 Sign Test Final N Value:

29 S+ Value:

29 Critical Value:

19 Sufficient Samples Collected:

Yes Maximum Value < Unitized DCGL:

Yes Median Value < Unitized DCGL:

Yes Mean Value < Unitized DCGL:

Yes Maximum Value < DCGLemc (Unity):

Yes Class I Standard Deviation <= Sigma:

Investigate All values <0.5 DCGLw Pass the Sign Test?

Yes Reject the Null Hypothesis?

Yes Does the Survey Unit Pass All Criteria?

Investigate Survey Passes Page 7 of 8 FSS Summary Report F8480011

Survey Unit Investigations and Results:

Seventy-one investigations were required for the scan measurements and the results are reported in Attachment 3'. The EMC unity rule was not exceeded as shown in Table 3-1.

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, the ALARA criterion has been met.

Changes in Initial Survey Unit Assumptions:

The survey unitwas designed as a Class 1 land survey and the sample results are consistent with that classification. The variability of the survey results was greater than the characterization data used for survey design. Seventy-one areas of elevated activity were detected. The EMC unity rule was not exceeded as shown in Table 3-1 therefore the EMC criterion was met.

==

Conclusion:==

The FSS of this survey unit was properly designed as a Class 1 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 Unity. 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 weremet.

It is concluded that survey unit F8480011 meets the release criteria of 10CFR20.1402.

Page 8 of 8 FSS Summary Report F8480011

Attachment I Maps April 3, 2008 Survey Unit F8480011

CD North Retention Basin Gamma Scan Survey 6812378E 1888205N 117 Gamma Scans for 100% coverage.

Final Basin Basin floor gamma scans are performed with a 44-10/SPA-3 and the western portion are 1m in width and 11m in length.

The eastern portion of the basin floor are 1 m in width and 12.5m in length with the exception of the northeast portion which ends at the basin wall.

00 00 OO F8480011-M1

North Retention Basin Survey Gamma/Soil Sample Directs 6812378E 1888205N,,

5

'26:""2 o Random start point W-E 6, S-N 25 determined using Random Trials 25 2

3 24 spreadsheet.

1.. -..

X.....

6812384E -

"*"Start point is 1.5 meters from west edge 1888175N 20 0...

.of the basin and 9.3 meters from the 15 16 87 19 "north edge of the basin.

X X X

C X

.Sample points on 7.5 meter grid.

08 09 10 11 12

,o:x.....

X

...x x.....

x

01.

.4 Final Effluent-\\"

En Basin 00 00 1`4Q40011 640

0 North Retention Basin ISOCS Gamma Scan Survey 6812378E 1888205N 109 Gamma Scans for 100% coverage.

Gamma scans are 4 meters center to center cj~j Final Effluent-Basin I

"t 00 00 F8480011-M3

CD 0

rjI rj~

00 00 North Retention Basin Gamma Scan Survey 6812378E 1888205N 117 Gamma Scans for 100% coverage.

68 44-10 Gamma Scans for 100% coverage of the basin floor.

Basin floor gamma scans are performed with a 44-1O/SPA-3 and the western portion are Im in width and 11m in length.

The eastern portion of the basin floor are 1 m in width and 12.5m in length with the exception of the northeast portion which ends at the basin wall.

F8480011-M4 Instrumentation April 3, 2008 Survey Unit F8480011

Table 2-1. Survey Unit Instrumentation Detector Detector Serial Instrument Model MDC No.No.

SN/A 05069128 Soil - 0.288 pCi/g Cs-137 Soil - 0.124 pCi/g Co-60 N/A 2983947 Soil - 0.201 pCi/g Cs-137 SC Soil - 0.223 pCi/g Co-60 2350-1 44-10 171992 5.2 pCi/g Cs-137 2350-1 44-10 171995 5.2 pCi/g Cs-137 Table 2-2. Investigation Criteria and DCGL Instrument Parameter Value ISOCS Investigation Criteria - Scan Soil - 26.3 pCi/g Cs-137 Soil - 6.3 pCi/g Co-60 52.6 Cs-137 All DCGLw 12.6 Co-60 All DCGLEMc 64.6 Cs-137 Investigation Criteria -

Nal Scan 8055 cpm Page 2 of 2 Att. 2 Instrumentation 1

F8480011 Investigation April 3, 2008 Survey Unit F8480011

Table 3-1 Survey Unit Investigation Investigation Initial Value Investigation Elevated Area

.Investigation DCGLemc Grid T

mUnity Grid Level (pCi/g)

(pCi/g)

Result (pCi/g) Area (m2)

Factor DCGLemc Result (pCig)

Fractioni 1

52.6 136 11.9 0.5 11.3 1188.76 11.9 0.0084 051

.295

__D___

126 1

4.99.

0.644 0

0.5 I

0.644-0.0019 2

52.6 18.5 18.5 0.5 11.3 1188.76 18.5 0.0140 2

261.07 1.07

.0.5 1:1.8....295 1..07 O'.008' 3

52.6 58 2.17 0.5 11.3 1188.76 2.17 0.0003 3

12.6.....1.32'.

0.17 0.-5 11.8

~

295 0.17 0.0002ý 4

52.6 17.3 17.3 0.5 11.3 1188.76 17.3 0.0130 4

260.9ý21 0.2 05 A 1.B 295

-0.921

-0.0028 5

52.6 18.8 18.8 0.5 11.3 1188.76 18.8 0.0143 5

1.6>

0.926' 0.96:~

11.8 295x 0!926 002 9

52.6 42.9 9.44 0.5 11.3 1188.76 9.44 0.0064 69 12.6

- 0662 3.75-0.5

.1:.8 29...

375.

0.0124 10 52.6 10.6 10.6 0.5 11.3 1188.76 10.6 0.0074 10 1.'

0.147014 0.5.

111.ý8-2:95 0O.1.41 0.01002:

11 52.6 26.7 26.7

.0.5 11.3 1188.76 26.7 0.0209 1 1.1 6

0.798 0 :.798 -

0.5.5 118.

295 0798.

024 13 52.6 0.512 0.512 0.5 11.3 1188.76 0.512 0.0000 130.188 0.1.88-:.:;.

0.5.

11.8 295 0.188 0.0003 15 52.6 17.5 17.5 0.5 11.3 1188.76 17.5 0.0132 151:2.6 0.394 0

-9 05 1.8 ~.

295 0.394 0.0010

-17 52.6 13.2 13.2 0.5 11.3 1188.76 13.2 0.0095 17 1226.......0.148 0D.148 0.5 11.8 295 0.148 00002 19 52.6 8.28 8.28 0.5 11.3 1188.76 8.28 0.0054 19 12.6 0.278 0.278&

0.5 11.8*

295 0,278 0.0006 Page 2 of 7 Att. 3 Investigation F8480012

Investigation Initial Value Investigation Elevated Area Investigation DCGLemc Grid Level (pCi/g)

(pCi/g)

Result (pCi/g) Area (m2)

Factor DCGLemc Iesut (pCigg)

Fractionity 23 52.6 24 24 0.5 11.3 1188.76 24 0.0186

.23 12.6 0.19 "0.196 05.7:

11.8 295 0.196 O.0003k 27 52.6 18.1 18.1 0.5 11.3 1188.76 18.1 0.0137

-27::

12.6-O. 483 0.483

0.

7 11.8, 295 0.483 0.0013 29 52.6 139 8.27 0.5 11.3 1188.76 8.27 0.0054 29 12.6.

2.8'.

0.473 0.5 1 1.a 295 0.473 000-13 30 52.6 99.4 8.27 0.5 11.3 1188.76 8.27 0.0054 30 12.6 0.613 0.473 0.5 -

11....

2295 0:473.

0.0013 31 52.6 37.6 1.61 1.61 11.3 1188.76 1.61 0.0000 31:12-.!6 2.*0:9 0.0951 01295 0.09.5 0.0000 32 52.6 39.8 1.61 0.5 11.3 1188.76 1.61 0.0000 32 12.6 0.251, 0.0951 0.5

1. 1.8 295 0.0.951,*

0M0000..

33 52.6 12 12 0.5 11.3 1188.76 12 0.0085 33

0.

12O....09 0.99 1 1.8 295 0.099.1 G 0.0000 35 52.6 7..58 7.58 0.5 11.3 1188.76 7.58 0.0048 35 12'.6 0.309 0.,309 0.5.I.?

1

.8 295

o. 039 0.0007, 43 52.6 4.96 4.96 0.5 11.3 1188.76 4.96 0.0026 43 12.6 01:

018 0.48, 0.5

>17.1,:8:

295 0.18 o0.0003ý 45-52.6 24.2 24.2 0.5 11.3 1188.76 24.2 0.0188

.4.

26.:.

0.328 0.2 11'.8 295.

y 0-..328:

0.0008 47 52.6 52.5 7.76 0.5 11.3 1188.76 7.76 0.0050

=:47 12.6 0:.--.

O.'906 3.04 0

<*5

-11.8 295 3.04 0.0100 50 52.6 14.7 14.7 0.5 11.3 1188.76 14.7 0.0108 50 12.6*

.559..*

0.559 0::.05

!8 295 0.559 0.0016; 52 52.6 23.3 23.3 0.5 11.3 1188.76 23.3 0.0180 52-12.6 0.58 0.58 0.5-11-.8 295

0.58 0.001:6 Page 3 of 7 Att. 3 Investigation F8480012

DCGLemc Grid Investigation Initial Value Investigation Elevated Area DCGLemc Investigation Unity L Level (pCi/g)

(pCiig)

I Result (pCi/g) Area (m2)

Factor Result (pCi/g)

Unity I

I Fraction 54 52.6 18.6 18.6

• 0.5 11.3 1188.76 18.6 0.0141 S. 54 260.766

.766 0.5*5 11.8 76.2950.766 0.0023 58 52.6 17.8 17.8 0.5 11.3 1188.76 17.8 0.0134 58 12.6 0.723 0.723 0.5 11.8

.295 0.723 0-::ý1,0021 60 52.6 20.1 20.1 0.5 11.3 1188.76 20.1 0.0153 60 12.6

~

0.8,54 0.854

.0.5 11.8.1:

295 0.854ý:-'

0.00.26 63 52.6 10.9 10.9 0.5 11.3 1188.76 M109 0.0076 63-12.6 0.213 0.213 0.5.

11.8 295 0.2130......0004 65 52.6 42.2 3.3 0.5 11.3 1188.76 3.3 0.0012 651.

12~.6 0.685..:

0.104

~

0.5 11.8 295

0.104.

0.0000-67 52.6 86.8 3.3 0.5 11.3 1188.76 3.3 0.0012

.67 12.6 0.794 0.10405 11.8..295 0.104..

0.0000 71 52.6 12.8 12.8 0.5 11.3 1188.76 12.8 0.0092 71.........12 1

0.061 0.0611 11.8

29. 5.0.0611:

0.0000 72 52.6 32.5 32.5 0.5 11.3 1188.76 32.5 0.0258

ý.72 1261.39 390.5 11.8,

- 295 1.3'0004

-4 74 52.6 17.8 17.8 0.5 11.3 1188.76 17.8 0.0134 74 1.2.6 0.494.

OA.94 0.5 118295 0.494 001 75 52.6 1.27 1.27 0.5 11.3 1188.76 1.27 0.0000

':ii75 :i012.6 0.329

.-0.329i 0.5 11.8 2

295 0.329 0.0008 76 52.6 82.1 7.08 0.5 11.3 1188.76 7.08 0.0044 76 12.*6 2.4

,0.186 0.5 11.8, 2 9.5 0.186 0.00 03 77 52.6 6.1 6.1 0.5 11.3 1188.76 6.1 0.0036 7712.6 0.132 0.132~.;.0.5 11.8.

295 0.132 0.0001 79 52.6 54.9 7.08 0.5 11.3 1188.76 7.08 0.0044 79 12.6 6.28 0i86 0.5, 11.8 295 0.186,

.0003 Page 4 of 7 Att. 3 Investigation F8480012

~DCGLemc Grid Investigation Initial Value Investigation Elevated Area DCGLerc Investigation Unity Level (pCiig)

(pCiig)

Result (pCiig) Area (m 2)

Factor Result (pCiig)

Unity

• jFraction 80 52.6 15.5 15.5 0.5 11.3 1188.76 15.5 0.0115 80:

12.6

0.1T55

0;.155 0.5

11. 8 295 0.155 0.0,002 81 52.6 8.79 8.79 0.5 11.3 1188.76 8.79

.0.0058

81.

12.6 01.1.79 0.179.

. 0.5 11.8

'295 01-79 0..0003 82 52.6 1.81 1.81 0.5 11.3 1188.76 1.81 0.0000 82 12.6 40.169 0.169 0.5 11.8 295 0.16 2.9 0.0002 85 52.6 40.3 2.98 0.5 11.3 1188.76 2.98 0.0009 85 12.6 2

1.28 0.5 11.8 295

1. 28 0.0040 86 52.6 45 2.98 0.5 11.3 1188.76 2.98 0.0009 86 12.6 2.57 1.28 0.5 11.8 295 1.2:8 0.0040 87 52.6 23 23 0.5 11.3 1188.76 23 0.0178

,87 12.6 0.339~

0.339 0.5

>11.8 295

~

0.339ý 0.0008 90 52.6 95.4 0.791 0.5 11.3 1188.76 0.791 0.0000 90 12.6 8.74 0.161 0.5 11.8 295 0.161 0.0042 91 52.6 96.7 0.761 0.5 11.3 1188.76 0.761 0.0000 91 126607 0.161 0.5 11.8 295 011000 92 52.6 43.31 0.0681 0.5 11.3 1188.76 0.0681 0.0000 92

,12.6 0,846 1

0.0741 0.5 1'1.8 295:

0.0741 0.0000 93 52.6 94.5 0.0681 0.5 11.3 1188.76 0.0681 0.0000 93, 12.6 2.811 0.0741 0.5 11.8, 295

0. 0741

-D.0000.

95 52.6 82.4 7.48 0.5 11.3 1188.76 7.48 0.0047 95:

12.6 0.997' 0.07,34 0.'5 11.8 295 0.0734 0.0000 96 52.6 37.7 7.48 0.5 11.3 1188.76 7.48 0.0047_

9612.6 1.7 0'.0734 0.5 11.8

.295 0.0734 000 97 52.6 12.1 12.1 0.5 11.3 1188.76 12.1 0.0086 97 1260290.289 0.5 11.8 2955-j 0.289 0 0007 Page 5 of 7 Att. 3 Investigation F8480012

Gri

',Investigation Unitym Investigation Initial Value Investigation Elevated Area DC G-emc Resu t i (p og Frc tnit Level (pCi/g)

(pCi/g)

Result (pCi/g) Area (m2)

Factor Result (pCi/g).

Fati 98 52.6 32.8 32.8 0.5 11.3 1188.76 32.8 0.0260 98 12.6 0.406

4016':..

0.:5 11-8:,

295 0406

-0.0010 101 52.6 35 4.92 0.5 11.3 1188.76 4.92 0.0026 101 12.60.547 410.5.

11 8 295.

.1004 102 52.6 25.7 25.7 0.5 11.3 1188.76 25.7 0.0201 102 12.6-0.43 0.4 0.5 11.8 295 0.43 0.0011 103 52.6 19.8 19.8 0.5 11.3 1188.76 19.8 0.0151 103 12.6 1.01 1.01 0.5 6

18 21 0.0031 104 52.6 13.7 13.7 0.5 11.3 1188.76 13.7 0.0100 101 12.6 0.263 0.2634 0.5 11.8 1295 0.263 0.0006 105 52.6 11.9 11.9 0.5 11.3 1188.76 11.9 0.0084 105 12.6 4

0.454 0.5 11.8 29.5.

0.454

,-'0.0012 106 52.6 13.7 13.7 0.5 11.3 1188.76 13.7 0.0100 1-06 12.6 0.4016 0.406 0.5 i11K8

295, 0.406 0.0010 107 52.6 9.49 9.49 0.5 11.3 1188.76 9.49 0.0064 1,07

.12.6 0.305 0.305-11.8 295

ý0.305 0.0007 108 52.6 33.6 11.6 0.5 11.3 1188.76 11.6 0.0082

108 12.6 0.6,67

ý0. 0995":

0-.5.

11.8

.295 0:.099,5 0.0Q00 109 52.6 2.08 2.08 0.5 11.3 1188.76 2.08 0.0002 109 126 0.098 0.9 0.5 11.8

~

29,5 0.098 0.06000 110 52.6 25.4 25.4 0.5 11.3 1188.76 25.4 0.0198 110 126

-0.737

.01737r

0. 5 11.8.....295 0.737.

0. 0022 i11 52.6 31.7 31.7 0.5 11.3 1188.76 31.7 0.0251 1112:.6 0.78 0.78.

0.5

-11.8 295 0.80.0023 112 52.6 16.6 16.6 0.5 11.3 1188.76 16.6 0.0124 112 2.6-0.51.

0.511" 0.5

1.

2:95 0.51 0.0014 Page 6 of 7 Att. 3 Investigation F8480012

Investigation Initial Value Investigation Elevated Area D

r Investigation DCGLenc Grid Level (pCiig)

(pCi/g)

Result (pCiig) Area (W2)

Factor DCGLemc Result (pCi/g)

Unity IFraction 113 52.6 42.4 7.6 0.5 11.3 1188.76 7.6 0.0048

.. ý11..

3 1 2.6 1.6 8 0.1 0 8

0.5.-

1 1..8 12 9 5 :.

-0.1 0 8 :

0 0i 8 : :. * : :..0005 01 00;.

1.

2 5 *..: :;i 1"

:,. : :,O08.: -..:O Go O : O 114 52.6 48.5 7.6 0.5 11.3 1188.76 7.6 0.0048 12.42.0 0.10&

0.5 118250000.0 114 12.6__

2.41.0.108 0

115 52.6 53.7 0.811 0.5 11.3 1188.76 0.811 0.0000 ii*5 12.6 2.84.

.0824 0.5.

11.8 295

.0.0824 0-.0000:

116 52.6 77.4 0.811 0.5 11.3 1188.76 0.811 0.0000 116ý 121.6 2.1 0.084 05

1.

295..

008 24:

0.0000 117 52.6 39.1 0.811

-0.5 11.3 1188.76 0.811 0.0000 11: i*

7 12.6.

2.48 0.0824 I

5:

11,.82 029 4*

0o00001 118 52.6 0.0446 0.0446 0.5 11.3 1188.76 0.0446 0.0000

.118 12.6 0.0326 0.0326 1-5 11.8 0

2935!

00526 0.0000 119 52.6 0.0408 0.0408 0.5 11.3 1188.76 0.0408 0.0000 1:19 12.6 0.0485 0.0485 04;5 f1.1.8 2951--ý 0.0485 0.0000.

DCGL =

SU Mean =

Survey Unit Remainder

• 52.6 1.86 0.0431

• • 12.6 0.0967 EMC Unity Sum 0.7099 Initial soil analysis found fifteen (15) grids (1, 3, 13, 29, 30, 47, 67, 76, 79, 90, 91, 93, 95, 115, and 116) exceeding the DCGLw. All grids exceeding the DCGLw were remediated below the DCGLw.

• Cs-137 and **Co-60 Survey Unit Remainder is 0.0431 The first result for each grid is the Cs-1 37, the second result (shaded) is Co-60.

Page 7 of 7 Att. 3 Investigation F8480012 Data Assessment April 3, 2008 Survey Unit F8480011

CD 00 4Cl Cl) 2r 00J 00 F8480011 Quantile Plot 0.250 -

0.200 -

0.150 N

S0.100 0.050 0.000 0.033 100

]

0 20 40 60 Percentile 80 Unitized Total Value -

Median -

- 75th Percentile -

- 50th Percentile

('D F8480011 Scatter Plot 0.250 0.200

--188 0.150 0.100 0

0 0.050 o

N 0

0 0 0-.00-0 0°o

-0.050 CD

• -0.100-------------------------------------------------------0o2

-0.150 1

i 1

I i l 1 i.

Measurement Locations 0

Unized Total Vakle

_ Average - -

+3StDeV'

-3StDev" 00 00

00 00 F8480011 Frequency Plot 24 23 22 21 20

>, 19 c18 (D 17 16 CT 15 L

14 LL 13 C-12 0

1.1 10 9

38 af) (17

.nQ 6

0 5

4 3

2 1

0 Bins - Upper End Value (Unitized Total)