ML082620091: Difference between revisions

From kanterella
Jump to navigation Jump to search
← Older editNewer edit →
VisualWikitext
Created page by program invented by StriderTol
Created page by program invented by StriderTol
Line 16: Line 16:


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


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


== Description:==
== Description:==


Operating History: Stairwell  
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".
# 3 is located in what used to be considered the radiologically controlled section of the Auxiliary Building.
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".
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:
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.
Scan measurements for beta radiation were taken on the interior surfaces of Stairwell  
Survey Unit Design Information:
# 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".Based on the classification procedure (DSIP-0020) and levels of gross activity reported, the interior 'surfaces of Stairwell  
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. -
# 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:
Page 2 of 8                         FSS Summary Report                             F8131402
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 m 2 were scanned for approximately 30% coverage.
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 ):
Samples of removable contamination were collected at each direct measurement location.
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 ):
The instrumentation used for the survey along with the MDC values are listed in Tables 2-1 and 2-2 in Attachment
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
: 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:
                                                                                    >3 N-Value:                           11 Design N-Value + 20%:                               14    NUREG-1575 Table 5-5 Design Min Samples N:                               14                      Class 2
DCGL (dpm/100 cm 2): Area Factor: Design DCGLemc (dpm/100 cm 2): LBGR (dpm/100 cm 2): Design Sigma (dpm/O00 cm 2): Type I Error: Type II Error: Predominant Nuclide: Sample Area (m2): Scan Area (m 2): 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
                                                    ,3.8                      Class 2 Grid Spacing L:
# 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.
Page 3 of 8                      FSS Summary Report                          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.
Survey Results:
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:
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.
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:
Table 2. Direct Measurement Results Measurement ID                Gross Activity (dpm/100 cm)
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:
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
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 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 cm 2): 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:
Table 3. Removable Surface Activity Results Measurement ID        Surface Beta Activity (dpm/100 cm 2 )
Yes Maximum Value < DCGL: Yes Median Value < DCGL: Yes Mean Value < DCGL: Yes Maximum Value < DCGLemc: N/A Class 2 Total Standard Deviation
F8131402C0001SM                        -0.95
<= Sigma: Yes Pass the Sign Test? Yes Reject the Null Hypothesis?
                .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
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:
Survey Unit Data Assessment:
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 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 unit was designed as a Class 2 structure survey and the sample results are consistent with that classification.
Page 6 of 8                        FSS Summary Report                          F8131402
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 1OCFR20.1402.
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):
Page 8 of 8 FSS Summary Report F8131402 Attachment 1 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-t&#xfd;j E.EY, 31'-3&#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~a cj~00 KEY PLANS PLAN VIEW ElE. 20-0" REFLECTED CEILING VIEW REFLECTED CEILING VIEW m"E. a1 l-0i-PLAN VIEW.EUV. 27'--6 REFLECTED CEILING VIEW 0E". t"-3" PLANV, IE EIEV. 3V-7,t* SCAN UNWT CosISS OF 3STAIR RIERS AMD 3 SDWJ TREWDS 0 -3E STAIR #3 RMS 210 & 318 FLOOR PLAN BETA SCAN MEASUREMENT LOCATIONS F8131402-M1
Total Standard Deviation    (dpm/100    2 cm ):      440      Based on samples and backgrounds.
&#xfd;1300o.04c SHEET 1 of 2 RC RAYM 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 Attachment 2 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 Attachment 3 Investigation June 3, 2008 Survey Unit F8131402 (none required)
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
Attachment 4 Data Assessment June 3, 2008 Survey Unit F8131402 t'j 0 cj&#xfd;00 C)F8131402 Gross Activity Sample Results Quantile Plot DCGL = 43000 dpm/1 00cm 2 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
Survey Unit Investigations and Results:
.50th Percentile F8131402 Gross Activity Sample Results Scatter Plot DCGL = 43000 dpm!100cm' 4000 3500 -a ---a a .--a a -a a a -a --a -3524 E 3000 a o-2500 --o o -o o C) cL2000*1~0 0> ,1500 o 0: 1000*~~~~~ a a a a ami, am a a a , , a a, , a a a* a. aw a a, t a a a a am a ,- 887 500 0 " " In M ImMeawuremenwtMLw MtMons 0 CA 00 0 0 0 0 0 Measurement Locationis 0- o Gross Activity -Average -"+3StDev --"3StDev k ) I i i i ! l i i l il I. l l i l li l[ I i W I ..
No investigations were required for either direct or scan measurements and no investigation results are reported.
CD F8131402 Gross Activity Frequency Plot DCGL = 43000 dpm/I OOcm 2 At)0 6 5 4 3 2 1 " ID- CT)2 0D IN-T- T- CO-0-cc Itj 00 Bins -Upper End Value (dpm/l 00cm2)}}
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
 
Attachment 1 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-t&#xfd;j E.EY, 31'-3 0  1  2   3 4 SCALE METERS
&#xfd;lT                                            AUXILIARY BUILDING EL 20 00                                          STAIR #3    ROOMS 210 & 318 BETA DIRECT/LOOSE SURFACE ACTIVITY MEASUREMENT LOCATIONS F8131 402-M2
 
(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
                      .EUV. 27'--6                0E". t"-3" PLANV, IE EIEV.3V-7,t 00
* SCAN UNWTCosISS STAIR    #3 RMS 210 & 318 FLOOR PLAN OF 3STAIR RIERS                                                                                    BETA SCAN AMD3 SDWJTREWDS                                                                              MEASUREMENT LOCATIONS 0 - SCAL*      3E F8131402-M1
                                                                                      &#xfd;1300o.04c        SHEET 1 of 2     RC RAYM
 
0 4-1 EL  0-EL 31-3j' EL 23-2' EL 20-0*
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*
AUXILARY BUILDING EL 20 00                                                                            STAIR    #*  RMS 210 & 31B WALL        ELEV BETA SCAN w.
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)
 
Attachment 4 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
0            20        40          60              80"        100 Percentile 00
* Direct Measurements (dpm/100cm2) -medlan  -  -. -75th Percentile . 50th Percentile C)
 
F8131402 Gross Activity Sample Results Scatter Plot DCGL = 43000 dpm!100cm' 4000 3500 -      -
a  - -          a a                  a -a      -                        -            a a- a      a-  -    .
                                                                                                                                  -
a    3524 E 3000 a                                                                                                                        o
  -2500                                                --  o              o              -                    o                  o C) cL2000
>    ,1500        *1~0 o0                                                0
:  1000        a
              *~~~~~  a  a a            am ami,    a     a a,    ,  a  a,
                                                                        ,    a a  a*        a. aw  a   a,t      a a a a am  a
                                                                                                                                  ,-   887 500 0                                          "                                            "
0        CA        00                                  0 0    00            0 In  ImMeawuremenwtMLw M                                                                          MtMons Measurement Locationis 0-                             o   Gross Activity -               Average -    "+3StDev              -  -      "3StDev k)                            I      i ii    ! l i il    il I.                   l l i l li l[            I                  iW  I    . .
 
F8131402 Gross Activity Frequency Plot 2
DCGL = 43000 dpm/I OOcm 6
5 CD At) 4 0
3 2
1 "
ID-   CT)2  0D    IN-             0-T-     T-   CO-                         cc Itj 00 Bins - Upper End Value (dpm/l 00cm2)}}

Revision as of 12:50, 14 November 2019

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 cm 2 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 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 ):

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 ):

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

>3 N-Value: 11 Design N-Value + 20%: 14 NUREG-1575 Table 5-5 Design Min Samples N: 14 Class 2

,3.8 Class 2 Grid Spacing L:

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 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.

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

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

F8131402C0001SM -0.95

.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

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 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):

Total Standard Deviation (dpm/100 2 cm ): 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

Attachment 1 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 0 1 2 3 4 SCALE METERS

ýlT AUXILIARY BUILDING EL 20 00 STAIR #3 ROOMS 210 & 318 BETA DIRECT/LOOSE SURFACE ACTIVITY MEASUREMENT LOCATIONS F8131 402-M2

(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

.EUV. 27'--6 0E". t"-3" PLANV, IE EIEV.3V-7,t 00

  • SCAN UNWTCosISS STAIR #3 RMS 210 & 318 FLOOR PLAN OF 3STAIR RIERS BETA SCAN AMD3 SDWJTREWDS MEASUREMENT LOCATIONS 0 - SCAL* 3E F8131402-M1

ý1300o.04c SHEET 1 of 2 RC RAYM

0 4-1 EL 0-EL 31-3j' EL 23-2' EL 20-0*

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*

AUXILARY BUILDING EL 20 00 STAIR #* RMS 210 & 31B WALL ELEV BETA SCAN w.

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)

Attachment 4 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 cjý I 1,500 4-3J 1,000 500 0

0 20 40 60 80" 100 Percentile 00

  • Direct Measurements (dpm/100cm2) -medlan - -. -75th Percentile . 50th Percentile C)

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

a - - a a a -a - - a a- a a- - .

-

a 3524 E 3000 a o

-2500 -- o o - o o C) cL2000

> ,1500 *1~0 o0 0

1000 a
  • ~~~~~ a a a am ami, a a a, , a a,

, a a a* a. aw a a,t a a a a am a

,- 887 500 0 " "

0 CA 00 0 0 00 0 In ImMeawuremenwtMLw M MtMons Measurement Locationis 0- o Gross Activity - Average - "+3StDev - - "3StDev k) I i ii  ! l i il il I. l l i l li l[ I iW I . .

F8131402 Gross Activity Frequency Plot 2

DCGL = 43000 dpm/I OOcm 6

5 CD At) 4 0

3 2

1 "

ID- CT)2 0D IN- 0-T- T- CO- cc Itj 00 Bins - Upper End Value (dpm/l 00cm2)

Retrieved from "https://kanterella.com/w/index.php?title=ML082620091&oldid=2153241"