ML17065A035

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Final Status Survey Report, September 26, 2016, Iosb Storage Cell B-2, Survey Unit F8300203
ML17065A035
Person / Time
Site: Rancho Seco
Issue date: 11/23/2016
From:
Sacramento Municipal Utility District (SMUD)
To:
Office of Nuclear Material Safety and Safeguards
Shared Package
ML17065A032 List:
References
DPG 17-038, F8300203
Download: ML17065A035 (16)
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Text

Rancho Seco Final Status Survey Summary Report September 26, 2016 IOS8 Storage Cell 8-2 Survey Unit F8300203 FSS Engineer Approved 8y:-~~--..::~~ltff~~==--- Date:

ncho Seco Assets

FINAL STATUS SURVEY F8300203 Survey Unit:

F8300203, [nterirn Onsite Storage Building (IOSB) Storage Cell B-2 Survey Unit

Description:

Operating History: Designed primarily to store packaged radioactive waste containers safely, protected from the elements, and :maintain radiological dose as low as reasonably achievable {ALARA), each storage cell possibly stored media of many types, including filters, resins, contaminated chemicals, DAW, contaminated plant components and other contaminated items.

Site Characterization: Static measurements were made of the interior :surfaces of the storage cell, to confirm the absence or presence of plant-derived radionuclides.

Static measurements showed a mean gross activity level of 2,756 dpmllOO cm 2 and a maximum value of 3,155 dpm/100 cm2

  • Based on the levels of gross activity reported, tlne area was determined to be a Class 3 area.

survey-unit-Oesignlnformation:

  • 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. Static :measurement locations were randomly determined and 26 m2 were scanned for approximately 32%

coverage. The instrumentation used for the survey along with the MDC values are listed in Table 2-1Attachment2.

1 FSS Storage Cell B-2 f 8300203

FINAL STATUS SURVEY F8300203 Table 1, Survey Unit Design Parameters

'. .
  • _ >: *- EvaltiaJi9n<1nbufV~lu~,s *-~*-_ *_*_

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. t<>rom~ntS ,

Survey Package: F830 Storaqe Cell B-2 Survey Unit: 20 Class 03 SU Area (m 2 ) 24 Evaluator: JR DCGLw: 43,000 Gross Activity DCGL Area Factor N/A Class 3 Design DCGLemc (dpm/100cm 2 ): NIA Class 3 DCGLemc: N/A Class 3 LBGR: 21,500 Default = 50% DCGL Sigma: 183 Scoping Survey Data Type I error: 0.0'5 Type II error: 0.05 Predominant Nuclide Cs-137 Sample Area (m 2 ) N/A Total Instrument Efficiency: 0.129 Total Area Scanned (m 2 ): 7.51 Scan Coverage(%)

!- */32'.%/ Class 3 Choosing 'N/A' set$ material Material Type: N/A background to "O"

' .,)\ :/xt.-, *. * ': *

. _-._,_
cafo:u1@fo'~'\vai:ue.~>J-'._;-~::i,:.:;:**;\,:. >-- *. ,** _;_ *:;comm'e'niS*?--~~--:: /> <r Z1-o:: 1.645 Z1-13: .1.645 Sign p: 0.9986.5 Calculated Relative Shift: 117.4 Relative Shift Used: 3.0 Uses 3.0 if Relative Shift >3 N-Value: 1J N-Value+20%: 14 2 FSS Storage Cell B-2 F8300203

FINAL STATUS SURVEY F8300203 Survey Results:

A total of 15 direct measurements were made in f 8300203. The results of the static measurements are shown in Table 2. All of the static measurements were less than the DCGL. None of the scan measurements indicated areas of elevated activity. Swipe data did not indicate elevated activity levels above the MDA.

Table 2, Static Measurement Results Number

  • Sanfple#: Beta (cpm) . **.
  • Be~a (dpm) 1 F8300203X0001 223 1,729 2 F8300203X0002 277 2,147 3 F8300203X0003 255 1,977 4 F8300203X0004 282 2,186 5 F8300203X0005 238 1,845 6 F8300203X0006 254 1,969 7 F8300203X0007 264 2,047 8 F8300203X0008 285 2,209 9 F8300203X0009 255 1,977 10 F8300203X0010 245 1,899 11 F8300203X0011 301 2,333 12 F8300203X0012 231 1,791 13 F8300203X0013 257 1,992 14 F8300203X0014 284 2,202 15 F8300203X0015 244 1,891 Table 3 contains the statistical summary of the static measurement data for the Storage Cell B-2 Table 3, Beta Summary Statistics Beta Static Cell B-2 Mean 2,013 Median 1,977 Standard Deviation 173 Minimum 1,729 Maximum 2,333 Count 15 3 FSS Storage Cell B-2 f 8300203

FINAL STATUS SURVEY F8300203 Survey Unit Data Assessment:

The survey design required 14 static measurements for the Sign Test. A total of 15 static measurements were collected. 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.

Table 4, Data Assessment Results

  • . **coriimeiit5 Number of Samples: 15 Median: 1,977 Mean: 2,01 :3 .

Static Data Standard Deviation: 173 Maximum: 2,3:33 ,

Adjusted N Value: 14 S+ Value: *. 15 Critical Value: to Sufficient samples collected: *Pas:S Maximum value <DCGLw: Pass Median value <DCGLw: Pa~s .*

Mean value <DCGLw: *Pass Maximum value <DCGLemc:

  • NIA Sign test results: * **Pass

. *_;::; ;.fJ >{'. '(>~<J#.fr)~t $.&'tu{\:::,:,: : *;:.;;;;,: ;J; ;~.1.t~ ;: ".;: :_ :** -.* .*.. f:: ¢9m_ITI~nis~;* . *:.: :*. >/ _'.

The survey unit passes all conditions: Pass 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, the ALARA criterion has been met.

Changes in Initial Survey Unit Assumptions:

The survey unit was designed as a Class 3 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.

4 FSS Storage Cell B-2 f 8300203

FINAL STATUS SURVEY F8300203

==

Conclusion:==

The FSS of this survey unit was properly designed as a Class 3 survey based on the results of the scoping survey. 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 static measurements were less than the DCGL. No investigations were required.

The static 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 F8300203 meets the release criteria of 10CFR20.l402.

5 FSS Storage Cell B-2 f 8300203

Attachment 1 Maps September 26, 2016 Survey Unit F8300203

A- 1 A-2 A-3

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e 8-3 C-J o.J

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=:-1 !:-:2:  !:-3 F8.3002GJllOO 11

' !l

  • Z, lJ3~/1000'ti' ' f!l300203X0006

~ II * ,96$< pm* !:::JO CM l'530Q20.1)(0013 ~

- 992 Oj)I!" 100 cm ~ F&30020.l 9 13

  • 1,WT~lODcm"

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SMUD TIDEWATER Iii SMUD Pagel Att. l Maps f 8300203

Attachment 2 Instrumentation September 26, 2016 Survey Unit F8300203

Table 2-1. Survey Unit Instrumentation M~asu1'eme~t . :*:Mi.ni~tim Detectable Activity*~ *. J?.~frct~r Calibra.ti(m Pu~ oat~"*

1 . . * .

  • .' TY;p.e

.. ~ .

E;ffi~i¢D!!iCS Beta Static Ludlum Model Beta - 523 dpm/I 00 cm 2 12.9% 317899/33 I 973 Measurement 2350-1 2/10/17 Ludlum Model 44-116 B Detector Swipe Ludlum Model 2929 Alpha - 7 dpm/l 00 cm 2 36.9% 166716/170380 Measurements Ludlum Model 44- Beta - 78 dpm/ 100 cm 2 42.8% 11/3/16 10-1

  • Minimum detectable activities for the count rate instrumentation were calculated in accordance with NUREG-1507, "Minimum Detectable Concentrations with Typical Radiation Survey Instruments for Various Contaminants and Field Conditions (U.S. NRC, 1997).

b Detectors are required to be calibrated once every 12 months. Calibration due date indicates the date by which the detector must be calibrated again.

cm 2 =square centimeters cpm = counts per minute dpm =disintegrations per minute Page 1 Att. 2 Instrumentation f 8300203

Static Measurement MDA Variables Beta Survey Type 317899 Detector Number 195 Background count rate (cpm) 1 Count Time (min) 0.130 Efficiency 100 Area of Detector (cm 2)

Constants 60 sec/min 2.54 cm/in Assumptions Background count time and sample count time are equivalent Calculate Static MDA Static MDA =3 + 4.65(Br

  • t}°- 5/t
  • E

Where: Br Background Countrate t Count Time (min)

E Efficiency A Area of detector (cm 2 )

Static MDA 523 dpm/100 cm 2 Page 2 Att. 2 Instrumentation f 8300203

Attachment 3 Investigation September 26, 2016 Survey Unit F8300203 (none required)

Att. 3 Investigation f 8300203

Attachment 4 Data Assessment September 26, 2016 Survey Unit F8300203

Histogram for Beta Static Activity Storage Cell B-2 ~ Ac t ivity

NixnbcfdVllltics M......,,

Maicini.m so Skewo8\'t Kutmi:t 1~

1.728.681 2,333.33, 172.59

~~!

0Meon 2.on921 f;'IM.o.n 1.97b.7' 1 0 NonMI OmrbAion 0 Lett8i'is 0Moie8nt

/

/

1753 1814 1874 1935 1995 2116 zm 2237 Page 1 Att. 4 Data Assessment F8300203

Q-Q Plot for Beta Static Activity Storage Cell B-2 Aciivity N

  • 15 Mean.,2013 Sd .. 1726 Slope* 1733 2300 1r1erc.ept*20i3 Cooelat1on,B*0.007
  • aMtnl#"l6 2200 2100 1~

1800

  • 1.0 *0.5 QO Q5 1.0 1.5 Th eoretical Qu antiles (Standard Normal)

Page 2 Att. 4 Data Assessment f 8300203

Smea r_ Data_Ca lcul atio n_Sheet _101316 I IOSB Fin al Stat us Survey I LCl LC2 LC3 LC4 LC6 LC5 p CPM I~ d pm Date/Tim e of Count Sam p le Com m ents 1 F830 020 3 x 00001 SM Cell S- _ 49 1 09/1 6/16 10 :34 2 F830 020 J x 00002 SM Cell B-2 40 -20 09/16/16 10:3 5 3 F830 020 3 x 00003 SM Cell B-2 43 -13 09/ 16/16 10:36 4 F830 020 3 x 00004 SM Cell B- 2 53 10 09/16/ 16 10:3 7 5 F830 020 3 x 00005 SM Cell B-2 49 1 09/16/16 10:38 6 F830 020 3 x 00006 SM Cell B-2 56 17 09/1 6/1 6 10:39 7 I F830 I 020 3 x 000 0 7 SM Ce!! B-2 44 -10 09/ 16/ 16 10:40 8 F830 020 3 x 00008 SM Cel! B-2 38 -24 09/16/16 10:1.12 9 F830 020 3 x 00009 SM Cell B-2 59 24 09/16/16 10:43 10 F830 020 3 x 00010 SM Cell B-2 46 -6 09/16/16 10:46 11 F830 020 3 x 00011 SM Cell B-2 64 36 09/16/16 10:48 12 F8 30 0 20 3 x 00012 SM Cell 13-2 46 -6 09/16/16 10:49 I 13 FS30 020 3 x 00013 SM Celi B 2 43 -13 09/16/ 16 I 10:50 I 14 F830 0 20 3 x 00014 SM Cell 13 -2 47 -3 09/16/16 10:51 15 F830 020 3 x 00015 SM Ce ll B-2 47 -3 09/16/1 6 10:53 Co mm ents Gy sign atu re belo w , th e req uire d o urce check an d b ackgro und checks w e re satisfactorily p erformed prio r t o use o f th e in st ru m ent id en tified below.

Ludlum 2929 Benchtop Instrument bkg eff iciency bkg count 2929 S/N : 182597 rate time MDA 0.1 1 7 .0 4 10-1 S/ N:188736 a 0.364 cpm min dpm per are~

  • Date ~.11';'1 Tech A Sign/ //kA _//L_,, / lht-r. 9 10 48.5 1 77 .6 Tec h B Sien/ Da t e NIA Ca l Du e Date: 5/ 13/ 2017

~ 0.434 cpm mi n dpm per ar -.;1 Page 1of1

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