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| number = ML082620091
| number = ML082620091
| issue date = 06/03/2008
| issue date = 06/03/2008
| title = Final Status Survey Summary Report, June 3, 2008, Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0, Auxiliary Building, Survey Unit F8131402
| title = Final Status Survey Summary Report, June 3, 2008, Stairwell 3 Rooms 210 and 318, Above Elevation 20- 0, Auxiliary Building, Survey Unit F8131402
| author name = Stein M
| author name = Stein M
| author affiliation = Sacramento Municipal Utility District (SMUD)
| author affiliation = Sacramento Municipal Utility District (SMUD)
Line 16: Line 16:


=Text=
=Text=
{{#Wiki_filter:Rancho Seco Final Status Survey Summary Report June 3, 2008 Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0", Auxiliary Building Survey Unit F8131402 Prepared By:_       __              _      Date:2*     *0   .
{{#Wiki_filter:Rancho Seco Final Status Survey Summary Report June 3, 2008 Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0", Auxiliary Building Survey Unit F8131402 Prepared By:_
FSS Engineer Reviewed By:\,-Date:.k/JL(0i Lead FSS Engineer Approved By:     I   7       _            Date:   7-     -
Date:2*  
Dismantlement Superintendent, Radiological
*0 FSS Engineer Reviewed By:\\,-Date:.k/JL(0i Lead FSS Engineer Approved By: I 7
Date:
7-Dismantlement Superintendent, Radiological


FINAL STATUS SURVEY  
FINAL STATUS SURVEY  
Line 27: Line 29:


== Description:==
== Description:==
Operating History: Stairwell # 3 is located in what used to be considered the radiologically controlled section of the Auxiliary Building. The stairwell was assigned three room numbers as follows. Room # 116 is the section of the stairwell from elevation 0'- 0" (grade level) to elevation 10'- 0". Room # 210 is the section of the stairwell from elevation 10'- 0" to elevation 31'- 3". Room # 318 is the section of the stairwell from elevation 31 '- 3" to elevation 52'- 0".
Operating History: Stairwell # 3 is located in what used to be considered the radiologically controlled section of the Auxiliary Building. The stairwell was assigned three room numbers as follows. Room # 116 is the section of the stairwell from elevation 0'- 0" (grade level) to elevation 10'- 0". Room # 210 is the section of the stairwell from elevation 10'- 0" to elevation 31'- 3". Room # 318 is the section of the stairwell from elevation 31 '- 3" to elevation 52'- 0".
Site Characterization: Scan measurements for beta radiation were taken on the interior surfaces of Stairwell # 3. The measurements showed a mean gross activity level of 18,533 dpm/100 cm 2 and a maximum value of 192,616 dpm/100 cm 2 from grade level to elevation 20'- 0". The measurements showed a mean gross activity level of 4,595 dpmr/100 cm 2 and a maximum value of 10,529 dpm/l00 cm 2 above elevation 20'- 0".
Site Characterization: Scan measurements for beta radiation were taken on the interior surfaces of Stairwell # 3. The measurements showed a mean gross activity level of 18,533 dpm/100 cm 2 and a maximum value of 192,616 dpm/100 cm 2 from grade level to elevation 20'- 0". The measurements showed a mean gross activity level of 4,595 dpmr/100 cm 2 and a maximum value of 10,529 dpm/l00 cm2 above elevation 20'- 0".
Based on the classification procedure (DSIP-0020) and levels of gross activity reported, the interior 'surfaces of Stairwell # 3, from grade level to elevation 20'- 0", were determined to be a Class 1 area and, above elevation 20'- 0", were determined to be a Class 2 area.
Based on the classification procedure (DSIP-0020) and levels of gross activity reported, the interior 'surfaces of Stairwell # 3, from grade level to elevation 20'- 0", were determined to be a Class 1 area and, above elevation 20'- 0", were determined to be a Class 2 area.
Survey Unit Design Information:
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 62 m2 were scanned for approximately 30% coverage. Samples of removable contamination were collected at each direct measurement location. The instrumentation used for the survey along with the MDC values are listed in Tables 2-1 and 2-2 in Attachment 2. -
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 62 m2 were scanned for approximately 30% coverage. Samples of removable contamination were collected at each direct measurement location. 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                             F8131402
Page 2 of 8 FSS Summary Report F8131402


Table 1. Survey Unit Design Parameters Survey Design.                   Value                       Comment Parameter Survey Area:                       F813       Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0", Auxiliary Building Survey Unit:                         1402              Structure Surface Class:                           2              LTP Table 5-4 SU Area (m2):                         205 Evaluator:               Michael Stein DCGL (dpm/100   cm 2):                 43000          Gross Activity DCGL Area Factor:                         N/A                          Class 2 Design DCGLemc                           N/A                          Class 2 (dpm/100 cm 2 ):
Table 1. Survey Unit Design Parameters Survey Design.
LBGR   (dpm/100 cm 2):                 21500          Default = 50% DCGL Design Sigma (dpm/O00 cm 2):                     5461 Type I Error:                         0.05 Type II Error:                         0.05 Predominant Nuclide:                       Cs-137 Sample Area (m2):                         14.6                        Class 2 2                          62 Scan Area   (m ):
Value Comment Parameter Survey Area:
Scan Coverage (%):                         30%                          Class 2 1.645 1.645 Sign P:                   0.99865 Calculated Relative Shift:                           3.9 Relative Shift Used:                             3 Uses 3.0 if Relative Shift is
F813 Survey Unit:
                                                                                    >3 N-Value:                           11 Design N-Value + 20%:                               14    NUREG-1575 Table 5-5 Design Min Samples N:                               14                       Class 2
Class:
                                                    ,3.8                       Class 2 Grid Spacing L:
SU Area (m2):
Page 3 of 8                     FSS Summary Report                         F8131402
Evaluator:
DCGL (dpm/100 cm 2):
Area Factor:
Design DCGLemc (dpm/100 cm2):
LBGR (dpm/100 cm 2):
Design Sigma (dpm/O00 cm 2):
Type I Error:
Type II Error:
Predominant Nuclide:
Sample Area (m2):
Scan Area (m2):
Scan Coverage (%):
Sign P:
Calculated Relative Shift:
Relative Shift Used:
N-Value:
Design N-Value + 20%:
Design Min Samples N:
Grid Spacing L:
1402 2
205 Michael Stein 43000 N/A N/A 21500 5461 0.05 0.05 Cs-137 14.6 62 30%
1.645 1.645 0.99865 3.9 3
11 14 14
,3.8 Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0", Auxiliary Building Structure Surface LTP Table 5-4 Gross Activity DCGL Class 2 Class 2 Default = 50% DCGL Class 2 Class 2 Uses 3.0 if Relative Shift is
>3 NUREG-1575 Table 5-5 Class 2 Class 2 Page 3 of 8 FSS Summary Report F8131402


Survey Results:
Survey Results:
A total of 14 direct measurements were made in F8131402. The results including mean, median, standard deviation and range are shown in Table 2. All direct measurements were less than the DCGL. None of the scan measurements indicated areas of elevated activity. Scan activity ranged from 5,472 to 29,276 dpm/100 cm 2 , based on a surveyor efficiency of 0.5 and no background.subtracted. Samples for removable surface activity were all less than 10% of the DCGL as shown in Table 3. Removable surface activity samples were counted for alpha activity and none was detected at the MDC shown in Table 2-1 of Attachment 2.
A total of 14 direct measurements were made in F8131402. The results including mean, median, standard deviation and range are shown in Table 2. All direct measurements were less than the DCGL. None of the scan measurements indicated areas of elevated activity. Scan activity ranged from 5,472 to 29,276 dpm/100 cm2, based on a surveyor efficiency of 0.5 and no background.subtracted. Samples for removable surface activity were all less than 10% of the DCGL as shown in Table 3. Removable surface activity samples were counted for alpha activity and none was detected at the MDC shown in Table 2-1 of Attachment 2.
Table 2. Direct Measurement Results Measurement ID               Gross Activity (dpm/100 cm)
Table 2. Direct Measurement Results Measurement ID Gross Activity (dpm/100 cm)
F8131402-COOOIBD                             2105 F8131402-CO002BD                             2359 F8131402-CO003BD                             2271 F8131402-CO004BD                             2535 F8131402-CO005BD                             1400 F8131402-CO006BD                             2447 F8131402-CO007BD                             1797 F8131402-CO008BD                             2480 F8131402-CO009BD                             1576 F8131402-CO01OBD                             1587 F8131402-COOIIBD                             2469 F8131402-CO012BD                             2568 F8131402-CO013BD                             2811 F8131402-CO014BD                             2469 Mean:                           2205 Median:                           2403 Standard Deviation:                           440 Range:                 1400-2811 Page 4 of 8                       FSS Summary Report                           F8131402
F8131402-COOOIBD F8131402-CO002BD F8131402-CO003BD F8131402-CO004BD F8131402-CO005BD F8131402-CO006BD F8131402-CO007BD F8131402-CO008BD F8131402-CO009BD F8131402-CO01OBD F8131402-COOIIBD F8131402-CO012BD F8131402-CO013BD F8131402-CO014BD Mean:
Median:
Standard Deviation:
Range:
2105 2359 2271 2535 1400 2447 1797 2480 1576 1587 2469 2568 2811 2469 2205 2403 440 1400-2811 Page 4 of 8 FSS Summary Report F8131402


Table 3. Removable Surface Activity Results Measurement ID         Surface Beta Activity (dpm/100 cm 2 )
Table 3. Removable Surface Activity Results Measurement ID Surface Beta Activity (dpm/100 cm 2)
F8131402C0001SM                       -0.95
F8131402C0001SM
                .F8131402C0002SM                        0.34 F8131402C0003SM                      -3.53 F8131402C0004SM                        -2.24 F8131402C0005SM                        0.34 F8131402C0006SM                        -0.95 F8131402C0007SM                        -2.24 F8131402C0008SM                        4.22 F8131402C0009SM                        1.64 F8131402C0010SM                        -0.95 F8131402C0011SM                        -4.82 F8131402C0012SM                        -2.24 F8131402C0013SM                        -3.53 F8131402C0014SM                        -4.82 Mean:                      -1.41 Median:                      -1.59 Standard Deviation:                      2.51 Range:              -4.82 to 4.22 Page 5 of 8             FSS Summary Report                   F8131402
.F8131402C0002SM F8131402C0003SM F8131402C0004SM F8131402C0005SM F8131402C0006SM F8131402C0007SM F8131402C0008SM F8131402C0009SM F8131402C0010SM F8131402C0011SM F8131402C0012SM F8131402C0013SM F8131402C0014SM Mean:
Median:
Standard Deviation:
Range:
-0.95 0.34
-3.53
-2.24 0.34
-0.95
-2.24 4.22 1.64
-0.95
-4.82
-2.24
-3.53
-4.82
-1.41
-1.59 2.51
-4.82 to 4.22 Page 5 of 8 FSS Summary Report F8131402


Survey Unit Data Assessment:
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 4. 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.
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 4. 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 6 of 8                       FSS Summary Report                         F8131402
Page 6 of 8 FSS Summary Report F8131402


Table 4. Data Assessment Results Survey Results Parameter                 Value           Comment Material Background Used (dpm/I 00 cm 2 ):       N/A Ambient Background Used (dpm/100 cm 2):         N/A Average Ambient BKG   = 0 Actual Direct Measurements (N):             14 Median (dpm/100 cm2):       2403 Mean (dpm/100 cm 2 ):     2205 Direct Measurement Standard Deviation             440 (dpm/100 cm 2):
Table 4. Data Assessment Results Survey Results Parameter Value Comment Material Background Used (dpm/I 00 cm2):
Total Standard Deviation   (dpm/100   2 cm ):     440       Based on samples and backgrounds.
N/A Ambient Background Used (dpm/100 cm 2):
Maximum (dpm/100 cm 2).       2811 Material Type:         N/A   Background Subtract Not Applied 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 2 Total Standard Deviation <= Sigma:           Yes Pass the Sign Test?         Yes Reject the Null Hypothesis?           Yes Does the Survey Unit Pass All Criteria?           Yes Page 7 of 8                     FSS Summary Report                       F8131402
N/A Average Ambient BKG = 0 Actual Direct Measurements (N):
14 Median (dpm/100 cm2):
2403 Mean (dpm/100 cm 2):
2205 Direct Measurement Standard Deviation 440 (dpm/100 cm 2):
Total Standard Deviation (dpm/100 cm 2):
440 Based on samples and backgrounds.
Maximum (dpm/100 cm 2).
2811 Material Type:
N/A Background Subtract Not Applied 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 2 Total Standard Deviation <= Sigma:
Yes Pass the Sign Test?
Yes Reject the Null Hypothesis?
Yes Does the Survey Unit Pass All Criteria?
Yes Page 7 of 8 FSS Summary Report F8131402


Survey Unit Investigations and Results:
Survey Unit Investigations and Results:
Line 68: Line 133:
==
==
Conclusion:==
Conclusion:==
The FSS of this survey unit was properly designed as a Class 2 survey based on Table5-4 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. No direct measurements exceeded the DCGL of 43000 dpm/100 cm 2 and none of the removable surface activity measurements exceeded 10% of the DCGL. No investigations were required.
The FSS of this survey unit was properly designed as a Class 2 survey based on Table5-4 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. No direct measurements exceeded the DCGL of 43000 dpm/100 cm 2 and none of the removable surface activity measurements exceeded 10% of the DCGL. No investigations were required.
The direct measurement data supportrejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and that the data quality objectives were met.
The direct measurement data supportrejection 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 F8131402 meets the release criteria of 10CFR20.1402.
It is concluded that survey unit F8131402 meets the release criteria of 10CFR20.1402.
Page 8 of 8                         FSS Summary Report                             F8131402
Page 8 of 8 FSS Summary Report F8131402 Maps JJune 3, 2008 Survey Unit F8131402
 
Attachment 1 Maps JJune 3, 2008 Survey Unit F8131402


(D EL 40'-0' PLANLVIE ELEV. 201-01             EL 51-W~
(D EL 40'-0' PLANLVIE ELEV. 201-01 EL 51-W~
EL 2S-2" EL 20'-0" LKG NORTH                   LKG SOUTH             LKG WES' S".' 23Y-t&#xfd;j E.EY, 31'-3 0   1   2   3 4 SCALE METERS
EL 2S-2" EL 20'-0" LKG NORTH LKG SOUTH LKG WES' S".' 23Y-t&#xfd;j E.EY, 31'-3
&#xfd;lT                                            AUXILIARY BUILDING EL 20 00                                          STAIR #3   ROOMS 210 & 318 BETA DIRECT/LOOSE SURFACE ACTIVITY MEASUREMENT LOCATIONS F8131 402-M2
&#xfd;lT 00 0
1 2
3 4
SCALE METERS AUXILIARY BUILDING EL 20 STAIR #3 ROOMS 210 & 318 BETA DIRECT/LOOSE SURFACE ACTIVITY MEASUREMENT LOCATIONS F8131 402-M2


(t~
(t~
a KEY PLANS PLAN VIEW               REFLECTED CEILING VIEW     REFLECTED CEILING VIEW ElE. 20-0"                                              m"E. a1 l-0i-cj~                  PLAN VIEW              REFLECTED CEILING VIEW
a cj~
                      .EUV. 27'--6                 0E". t"-3" PLANV, IE EIEV.3V-7,t 00
00 KEY PLANS PLAN VIEW ElE. 20-0" REFLECTED CEILING VIEW REFLECTED CEILING VIEW m"E. a1 l-0i-PLAN VIEW
* SCAN UNWTCosISS STAIR     #3 RMS 210 & 318 FLOOR PLAN OF 3STAIR RIERS                                                                                    BETA SCAN AMD3 SDWJTREWDS                                                                              MEASUREMENT LOCATIONS 0 - SCAL*      3E F8131402-M1
.EUV. 27'--6 REFLECTED CEILING VIEW 0E".
                                                                                      &#xfd;1300o.04c       SHEET 1 of 2     RC RAYM
t"-3" PLANV, IE EIEV. 3V-7,t
 
* SCAN UNWT CosISS OF 3STAIR RIERS AMD 3 SDWJ TREWDS 0 -
0 4-1 EL  0-EL 31-3j' EL 23-2' EL 20-0*
SCAL*
ELEV LKG NORTH                ELEY LKG EAST                  ELEV LKG. SOUTH                    ELEV LXG WEST No~n ofOFL UNE 9.7              AT CO1 LINE R                  AT.VOL UNE 9,7                    WESTOf COL Lm*
3E STAIR #3 RMS 210 & 318 FLOOR PLAN BETA SCAN MEASUREMENT LOCATIONS F8131402-M1
AUXILARY BUILDING EL 20 00                                                                            STAIR    #*  RMS 210 & 31B WALL        ELEV BETA SCAN w.
&#xfd;1300o.04c SHEET 1 of 2 RC RAYM
0 1      2    3 S    MUN                        MEASUREMENT LOCATIONS SCALE HKETE unf DtF81                              31402-M1 Fnir Al A" 00-        SHEET *2of 2          RC RAWIONE
 
Attachment 2 Instrumentation June 3, 2008 Survey Unit F8131402
 
Table 2-1. Survey Unit Instrumentation Instrument                Detector              MDC Static            MDC Scan 2
Model; Serial No.      Model; Serial No.        (dpm/100 cm )          (dpm/100 cm 2 )
M2350; 203486          43-68B; 190476                  433                1033 Tennelec; 0401171                N/A                  5.9 dpm 11.7 dpma,P3          N/A Table 2-2. Investigation Criteria and DCGL Value Param eter                    (dpm/100    cm 2 )2 V l eC Investigation Criteria - Direct                43000 Investigation Criteria - Scan                  43000 DCGLw                                          43000 DCGLEMC                                        N/A Page 2 of 2                      Att. 2 Instrumentation                        F8131402


Attachment 3 Investigation June 3, 2008 Survey Unit F8131402 (none required)
0 4-1 EL 0-EL 31-3j' EL 23-2' EL 20-0*
ELEV LKG NORTH No~n of OFL UNE 9.7 ELEY LKG EAST AT CO1 LINE R ELEV LKG. SOUTH AT. VOL UNE 9,7 ELEV LXG WEST WEST Of COL Lm
* 00 w.
AUXILARY BUILDING EL 20 STAIR #*
RMS 210 & 31B WALL BETA SCAN S
MUN MEASUREMENT LOCATIONS unf DtF81 31402-M1 Fnir Al A" 00-SHEET *2 of 2 0
1 2
3 SCALE HKETE ELEV RC RAWIONE Instrumentation June 3, 2008 Survey Unit F8131402


Attachment 4 Data Assessment June 3, 2008 Survey Unit F8131402
Table 2-1. Survey Unit Instrumentation Instrument Detector MDC Static MDC Scan Model; Serial No.
Model; Serial No.
(dpm/100 cm 2 )
(dpm/100 cm 2 )
M2350; 203486 43-68B; 190476 433 1033 Tennelec; 0401171 N/A 5.9 dpm a, N/A 11.7 dpm P3 Table 2-2. Investigation Criteria and DCGL Value Param eter V l eC 2
(dpm/100 cm 2)
Investigation Criteria - Direct 43000 Investigation Criteria - Scan 43000 DCGLw 43000 DCGLEMC N/A Page 2 of 2 Att. 2 Instrumentation F8131402 Investigation June 3, 2008 Survey Unit F8131402 (none required)
Data Assessment June 3, 2008 Survey Unit F8131402


F8131402 Gross Activity Sample Results Quantile Plot t'j 0                              DCGL = 43000 dpm/1 00cm2 3,000 2,500 2403 2,000 cj&#xfd; I  1,500 4-3J 1,000 500 0
t'j 0
0             20         40           60               80"       100 Percentile 00
cj&#xfd; 00 C)
* Direct Measurements (dpm/100cm2) -medlan -  -. -75th Percentile . 50th Percentile C)
F8131402 Gross Activity Sample Results Quantile Plot DCGL = 43000 dpm/1 00cm2 I
4-3J 3,000 2,500 2,000 1,500 1,000 2403 500 0
0 20 40 60 80" 100 Percentile Direct Measurements (dpm/100cm2)  
-medlan  
-. -75th Percentile.
50th Percentile


F8131402 Gross Activity Sample Results Scatter Plot DCGL = 43000 dpm!100cm' 4000 3500 -      -
F8131402 Gross Activity Sample Results Scatter Plot DCGL = 43000 dpm!100cm' 4000 3500 -
a   - -          a a                   a -a     -                        -            a a- a       a-   -   .
a a a a a a a a a -
a    3524 E 3000 a                                                                                                                       o
a -
  -2500                                               --  o               o             -                    o                   o C) cL2000
3524 E 3000 a
>    ,1500        *1~0 o0                                                0
o
:   1000         a
-2500 o
              *~~~~~ a   a a             am ami,     a     a a,   ,  a a,
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Latest revision as of 15:04, 14 January 2025

Final Status Survey Summary Report, June 3, 2008, Stairwell 3 Rooms 210 and 318, Above Elevation 20- 0, Auxiliary Building, Survey Unit F8131402
ML082620091
Person / Time
Site: Rancho Seco
Issue date: 06/03/2008
From: Stein M
Sacramento Municipal Utility District (SMUD)
To:
NRC/FSME
References
MPC&D 08-064
Download: ML082620091 (19)
v • d • e


Text

Rancho Seco Final Status Survey Summary Report June 3, 2008 Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0", Auxiliary Building Survey Unit F8131402 Prepared By:_

Date:2*

  • 0 FSS Engineer Reviewed By:\\,-Date:.k/JL(0i Lead FSS Engineer Approved By: I 7

Date:

7-Dismantlement Superintendent, Radiological

FINAL STATUS SURVEY

SUMMARY

REPORT Survey Unit:

F8131402, Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0" of the Auxiliary Building Survey Unit

Description:

Operating History: Stairwell # 3 is located in what used to be considered the radiologically controlled section of the Auxiliary Building. The stairwell was assigned three room numbers as follows. Room # 116 is the section of the stairwell from elevation 0'- 0" (grade level) to elevation 10'- 0". Room # 210 is the section of the stairwell from elevation 10'- 0" to elevation 31'- 3". Room # 318 is the section of the stairwell from elevation 31 '- 3" to elevation 52'- 0".

Site Characterization: Scan measurements for beta radiation were taken on the interior surfaces of Stairwell # 3. The measurements showed a mean gross activity level of 18,533 dpm/100 cm 2 and a maximum value of 192,616 dpm/100 cm 2 from grade level to elevation 20'- 0". The measurements showed a mean gross activity level of 4,595 dpmr/100 cm 2 and a maximum value of 10,529 dpm/l00 cm2 above elevation 20'- 0".

Based on the classification procedure (DSIP-0020) and levels of gross activity reported, the interior 'surfaces of Stairwell # 3, from grade level to elevation 20'- 0", were determined to be a Class 1 area and, above elevation 20'- 0", were determined to be a Class 2 area.

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 62 m2 were scanned for approximately 30% coverage. Samples of removable contamination were collected at each direct measurement location. 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 F8131402

Table 1. Survey Unit Design Parameters Survey Design.

Value Comment Parameter Survey Area:

F813 Survey Unit:

Class:

SU Area (m2):

Evaluator:

DCGL (dpm/100 cm 2):

Area Factor:

Design DCGLemc (dpm/100 cm2):

LBGR (dpm/100 cm 2):

Design Sigma (dpm/O00 cm 2):

Type I Error:

Type II Error:

Predominant Nuclide:

Sample Area (m2):

Scan Area (m2):

Scan Coverage (%):

Sign P:

Calculated Relative Shift:

Relative Shift Used:

N-Value:

Design N-Value + 20%:

Design Min Samples N:

Grid Spacing L:

1402 2

205 Michael Stein 43000 N/A N/A 21500 5461 0.05 0.05 Cs-137 14.6 62 30%

1.645 1.645 0.99865 3.9 3

11 14 14

,3.8 Stairwell # 3 Rooms 210 and 318, Above Elevation 20'- 0", Auxiliary Building Structure Surface LTP Table 5-4 Gross Activity DCGL Class 2 Class 2 Default = 50% DCGL Class 2 Class 2 Uses 3.0 if Relative Shift is

>3 NUREG-1575 Table 5-5 Class 2 Class 2 Page 3 of 8 FSS Summary Report F8131402

Survey Results:

A total of 14 direct measurements were made in F8131402. The results including mean, median, standard deviation and range are shown in Table 2. All direct measurements were less than the DCGL. None of the scan measurements indicated areas of elevated activity. Scan activity ranged from 5,472 to 29,276 dpm/100 cm2, based on a surveyor efficiency of 0.5 and no background.subtracted. Samples for removable surface activity were all less than 10% of the DCGL as shown in Table 3. Removable surface activity samples were counted for alpha activity and none was detected at the MDC shown in Table 2-1 of Attachment 2.

Table 2. Direct Measurement Results Measurement ID Gross Activity (dpm/100 cm)

F8131402-COOOIBD F8131402-CO002BD F8131402-CO003BD F8131402-CO004BD F8131402-CO005BD F8131402-CO006BD F8131402-CO007BD F8131402-CO008BD F8131402-CO009BD F8131402-CO01OBD F8131402-COOIIBD F8131402-CO012BD F8131402-CO013BD F8131402-CO014BD Mean:

Median:

Standard Deviation:

Range:

2105 2359 2271 2535 1400 2447 1797 2480 1576 1587 2469 2568 2811 2469 2205 2403 440 1400-2811 Page 4 of 8 FSS Summary Report F8131402

Table 3. Removable Surface Activity Results Measurement ID Surface Beta Activity (dpm/100 cm 2)

F8131402C0001SM

.F8131402C0002SM F8131402C0003SM F8131402C0004SM F8131402C0005SM F8131402C0006SM F8131402C0007SM F8131402C0008SM F8131402C0009SM F8131402C0010SM F8131402C0011SM F8131402C0012SM F8131402C0013SM F8131402C0014SM Mean:

Median:

Standard Deviation:

Range:

-0.95 0.34

-3.53

-2.24 0.34

-0.95

-2.24 4.22 1.64

-0.95

-4.82

-2.24

-3.53

-4.82

-1.41

-1.59 2.51

-4.82 to 4.22 Page 5 of 8 FSS Summary Report F8131402

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 4. 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 6 of 8 FSS Summary Report F8131402

Table 4. Data Assessment Results Survey Results Parameter Value Comment Material Background Used (dpm/I 00 cm2):

N/A Ambient Background Used (dpm/100 cm 2):

N/A Average Ambient BKG = 0 Actual Direct Measurements (N):

14 Median (dpm/100 cm2):

2403 Mean (dpm/100 cm 2):

2205 Direct Measurement Standard Deviation 440 (dpm/100 cm 2):

Total Standard Deviation (dpm/100 cm 2):

440 Based on samples and backgrounds.

Maximum (dpm/100 cm 2).

2811 Material Type:

N/A Background Subtract Not Applied 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 2 Total Standard Deviation <= Sigma:

Yes Pass the Sign Test?

Yes Reject the Null Hypothesis?

Yes Does the Survey Unit Pass All Criteria?

Yes Page 7 of 8 FSS Summary Report F8131402

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), the ALARA criterion has been met.

Changes in Initial Survey Unit Assumptions:

The survey unit was designed as a Class 2 structure 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 2 survey based on Table5-4 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. No direct measurements exceeded the DCGL of 43000 dpm/100 cm 2 and none of the removable surface activity measurements exceeded 10% of the DCGL. No investigations were required.

The direct measurement data supportrejection 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 F8131402 meets the release criteria of 10CFR20.1402.

Page 8 of 8 FSS Summary Report F8131402 Maps JJune 3, 2008 Survey Unit F8131402

(D EL 40'-0' PLANLVIE ELEV. 201-01 EL 51-W~

EL 2S-2" EL 20'-0" LKG NORTH LKG SOUTH LKG WES' S".' 23Y-týj E.EY, 31'-3

ýlT 00 0

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SCALE METERS AUXILIARY BUILDING EL 20 STAIR #3 ROOMS 210 & 318 BETA DIRECT/LOOSE SURFACE ACTIVITY MEASUREMENT LOCATIONS F8131 402-M2

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00 KEY PLANS PLAN VIEW ElE. 20-0" REFLECTED CEILING VIEW REFLECTED CEILING VIEW m"E. a1 l-0i-PLAN VIEW

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1 2

3 SCALE HKETE ELEV RC RAWIONE Instrumentation June 3, 2008 Survey Unit F8131402

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

Model; Serial No.

(dpm/100 cm 2 )

(dpm/100 cm 2 )

M2350; 203486 43-68B; 190476 433 1033 Tennelec; 0401171 N/A 5.9 dpm a, N/A 11.7 dpm P3 Table 2-2. Investigation Criteria and DCGL Value Param eter V l eC 2

(dpm/100 cm 2)

Investigation Criteria - Direct 43000 Investigation Criteria - Scan 43000 DCGLw 43000 DCGLEMC N/A Page 2 of 2 Att. 2 Instrumentation F8131402 Investigation June 3, 2008 Survey Unit F8131402 (none required)

Data Assessment June 3, 2008 Survey Unit F8131402

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F8131402 Gross Activity Sample Results Quantile Plot DCGL = 43000 dpm/1 00cm2 I

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F8131402 Gross Activity Sample Results Scatter Plot DCGL = 43000 dpm!100cm' 4000 3500 -

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