ML17065A061

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Final Status Survey Summary Report, January 25, 2017, Iosb Loading Dock, Survey Unit F8300071
ML17065A061
Person / Time
Site: Rancho Seco
Issue date: 02/09/2017
From:
Sacramento Municipal Utility District (SMUD)
To:
Office of Nuclear Material Safety and Safeguards
Shared Package
ML17065A032 List:
References
DPG 17-038
Download: ML17065A061 (15)


Text

Rancho Seco Final Status Survey Summary Report January 25, 2017 IOSB Loading Doc~

Survey Unit F8300071 FSS Engineer Approved By: ~~ Date: *J~

~anager, R:nhOSeco Assets

FINAL STATUS SURVEY F8300071 Survey Unit:

F8300071, Interim Onsite Storage Building (IOSB) Loading Dock Class 1 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, activated reactor components, contaminated plant components and other contaminated items.

Site Characterization: Based upon the scanning results of the Truck Bay an elevated area was identified on the floor around and including the loading dock. Certain spots in the area exceeded the DCGLw but not the DCGLEMC* This area required remediation. The Truck bay was divided into a small Class 1 Survey Unit, buffered by a Class 2 Survey Unit. The remainder of the Bay was designated as a Cla$S 3 Survey Unit. The Class 3 and Class 2 areas are the subject of separate reports.

Survey Unit Design Information:

In accordance with MARSSIM Section 4.6, special considerations may be necessary for survey units with structure surface areas less than I 0 m2 or land areas less than I 00 m 2 . In this case, the number of data points obtained from the stati$tical tests is unnecessarily large and not appropriate for smaller survey unit areas. The data generated from these smaller survey units should be obtained based on judgment, rather than on systematic or random design, and compared individually to the DCGLs. This survey unit meets this criterion as the size is less than ten square meters (7 .5 m2).

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 based upon professional judgment and approximately I 00% of the area scanned. The instrumentation used for the survey along with the MDC values are listed in Table 2-1 Attachment 2.

FSS Loading Dock Class 1 F8300071

FINAL STATUS SURVEY F8300071 Table 1, Survey Unit Design Parameters

~! : ' .- *

  • Survey Packaqe: F830 Loadinq Dock Class 1 Survey Unit: 007 Class 1 SU Area (m 2) 7.5 Evaluator: JR DCGLw: 43,000 Gross Activity DCGL Area Factor 3.4 DTBD-05-003 DesiQn DCGLemc (dpm/100cm 2 ): 146,200 DCGLemc: 146,200 LBGR: 21,500 Default= 50% DCGL Sigma: 466 Truck Bay ScopinQ Type I error: 0:05 Type II error: 0.05 Predominant Nuclide Cs-137 Sample Area (m2) N/A Total Instrument Efficiency: 0.130 Total Area Scanned (m 2): 7.5 Scan Coveraqe (%) '.:X:1o6o/d:: Class 1 Choosing 'N/A' sets material Material Type: NIA backQround to "O"
,
* ,J <.:;\**.** *:c~icuiat:eava1l.i~_~\i:  :;  :;:,;:~;v/ . *' ~?':*. >tJ ':,::cBmmeiit$:* .,.; /,~,  :.:'**~.  ;:.
  • Z1-a: 1:645.

Z1-a: 1.645 SiQn p: 0.99865 Calculated Relative Shift: 46.1 ,

Relative Shift Used: 3.0 Uses 3.0 if Relative Shift >3 Values selected based upon N-Value: 15 Judqement Values selected based upon N-Value+20%: 15 Judqement Survey Results:

A total of 15 direct measurements were made in f 8300071. 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.

2 FSS Loading Dock Class 1 F8300071

FINAL STATUS SURVEY F8300071 Table 2, Static Measurement Results Nurri~er . :*$ample# B~t,~ (yP!ll) .. ., B~t~ (dpm), *.

1 F8300071C00001 959 7,265 2 F8300071C00002 360 2,727 3 F8300071C00003 377 2,856 4 F8300071C00004 407 3,083 5 F8300071C00005 533 4,038 6 F8300071C00006 477 3,614 7 F8300071C00007 390 2,955 8 F8300071C00008 331 2,508 9 F8300071C00009 254 1,924 10 F8300071C00010 321 2,432 11 F8300071MOOO11 280 2, 121 12 F8300071 MOOO 12 634 4,803 13 F8300071 M00013 425 3,220 14 F8300071 M00014 532 4,030 15 F8300071 M00015 249 1,886 Table 3 contains the statistical summary of the static measurement data for the Loading Dock Class l.

Table 3, Beta Summary Statistics Beta Static Loading Dock Class 1 Mean 3,297 Median 2,955 Standard Deviation 1,376 Minimum 1,886 Maximum 7,265.

Count 15 Survey Unit Data Assessment:

The survey design was based upon professional judgement and resulted in 15 static measurements. Following the guidance in MARSSIM Section 4.6, these values are compared directly to the DCGLw.

The comparison and the results are presented in Table 4. The sample mean and median values were less than the DCGL.

3 FSS Loading Dock Class l F8300071

FINAL STATUS SURVEY F8300071 Table 4, Data Assessment Results

.comment's*

Number of Samples: 15 Median: 2,955, Mean: 3,297 Static Data Standard Oeviation: 1,376 Maximum: 7,265

': -.c_riterla 5atista~tfo'n .* . -. Comrti~nt~

.,. '. *i Sufficient samples collected: Pass Maximum value <DCGLw: Pass Median value <DCGLw: Pass

  • Mean value <DCGLw: Pass Maximum value <DCGLemc: N/A Si!:in test results: N/A 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 I 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. However, no individual measurement exceeded the DCGL. No potential areas of elevated activity were detected.

==

Conclusion:==

The FSS of this survey unit was properly designed as a Class I 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 F830007 l meets the release criteria of I OCFR20. l 402.

4 FSS Loading Dock Class 1 F8300071

Attachment 1 Maps January 30, 2017 Survey Unit F8300071

F8300071 M00009 I~= 1,924 dpm/100 cm 2 F8300071 M00015 F8300071 M00006 I~= 1.886 dpm/100 cm 2 0 = 3 ,614 dpm/100 cm 2 F8300071 M00012 p = 4,803 dpm/100 cm 2 F8300071C0000 1 F8300071 M00014 p = 7,265 dpm/100 cm 2 P= 4,030 dpm/100 cm 2 F8300071 M00011 l

p = 2, 121 dpm/100 cm 2 F8300071C00004

~ = 3.083 dpm/100 cm'

-)

F8300071C00008 B= 2,508 dpm/100 cm 2 F8300071C00003 I~ = 2,856 dpm/100 cm 2 0

F8300071C00005 _/

p = 4,038 dpm/100 cm2 F8300071C00002 SMUD TIDEWATER IN I R /\ OIOU';GtCA L SCnvlCC:S I\ = 2,727 dprn/100 cm/

oottoc No.: A e~ 'J ldl f SMUD Location: -t.:m rhn *u~!" o Approved by.

F8300071C00007 /

Dro w'n g t~o .: W\

O.escriptlcn : LcJd .. 111: t)o c:'< l ~ ;i!.~* l 13 = 2,955 dpm/100 crn 2 Orown B . *. / l ro:. F8300071C00010 Approval dole: B=2,432 dpm/100 crn 2 Rev No.:

Page J Att. 1 Maps F8300071

Attachment 2 Instrumentation January 30, 2017 Survey Unit F8300071

Table 2-1. Survey Unit Instrumentation

  • Me~sure~ent.
  • Mini mu. rrt*,. Petecta hie Activify~ . *Detedor .
  • C~Hbrat.ion
  • **
  • JnstrumenfType ,*

.Effici°~~cies Type

  • *,* * 'F' nue 'i>ateb Beta Static Ludlum Model Beta - 566 dpm/100 cm 2 13.2% 317897/331972 Measurement 2350-1 2/10/17 Ludlum Model 44-1 16 B Detector Swipe Ludlum Model 2929 Beta - 76 dpm/l 00 cm 2 43.4% 182597/188736 Measurements Ludlum Model 44- 5/13/17 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

~pm= disintegrations per minute Page I Att. 2 Instrumentation F8300071

Static Measurement MDA Beta Survey Type PR331972 Detector Number 238 Background count rate {cpm)

Count Time (min) 0.132 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) 0 *5/t
  • E

Where: Br Background Countrate t Count Time (min)

E Efficiency A Area of detector (cm2)

Static MDA 566 dpm/100 cm 2 Page 2 Att. 2 Instrumentation F8300071

.Attachment 3

,Investigation January 30, 2017 Survey Unit F8300071 (none required)

Att. 3 Investigation F8300071

Attachment 4 Data Assessment January 30, 2017 Survey Unit F8300071

Histogram for Beta Static Activity (dpm/100crn2) Loading Dock Class 1 1 A ctiv~

I 6 Numbe1 of Values 15j Minimum 1.886.31

/"' Ma-.:irnum 7.265.15

/ SD 1.376.271 5 Skewne** 1.84 5

Ku1tosis 4.32 I BMean BMedian B Nounal 0 isllibulion 0Less Bins OMoreBins 3.297.47 2.954.551 g

3

~3 u..

2 1 1 2152 2689 3227 3765 0

4303

  • 4841 0

5379 0

5917 0

6455 6992 Page I Att. 4 Data Assessment F8300071

Acliv~

Q-Q Plot for Beta Static Activity (dpm/100cm2) Loading Dock Class 1 lh15

'7200

  • Mean= 3297 Sd = 1376 Slope* 1305 lnteicept = 3297 6400 *cooelalion, R =0.906 l!lil Best Fit Line 5600

~

4800

  • u

<(

4000 3200 2400

-1.5 -1.0 45 00 05 1.0 1.5 Theoretical Quantiles (Standard Normal)

Page2 Att. 4 Data Assessment F8300071

F8300071 Smear _calc IOSB Final Status Survey I I1 LCl F830 lC2 007 LC3 lC4 1 c LC6 00001 lC5 SM load Dock f3CPM 39 f3dpm

-18 Date/TI me of Count 12/29/16 1303 Sample Comments 2 F830 007 1 c 00002. SM Load Dock 44 -6 12/29/16 1304 3 F830 007 l c 00003 SM Load Dock 42 -11 12/29/16 1305 4 F830 007 1 c 00004 SM Load Dock 36 -25 12/29/16 1306 s F830 007 1 c 00005 SM Load Dock 45 -4 12/29/16 1307 6 F830 007 1 c 00006 SM load Dock 46 -2 12/29/16 1308 7 f830 007 1 c* 00007 SM* Load Dock 57 24 12/29/15 1311 8 f830 007 1 c (){J()()8 SM Load Dock 50 31 12/29/15 1312 9 f830 007 1 c 00009 SM Load Dock 36 -25 12/29/16 1313 10 f830 007 1 c 00010 SM Load Dode 43 -9 12/29/16 1314 11 F830 007. 1 c Oooll SM load Dock 53 15 12/29/15 1315 12 F830 007 1 c 00012 SM Load Dock 40 -15 12/29/15 1315 13 f830 007 1 c. 00013 SM Load.Dock 42 -11 12/29/16 1317 14 F830 007 1 .c ~4 SM. Load Dock 45 -4 12/29/16 1319 15 F830 007 1 *c 00015 SM Load Dode 41 -13 12/29/16 1320 Comments By signl!ture below, the required source check and background checks were satisfactorily performed prior to use of the instrument identified below.

Ludlum 2929 Benchtop Instrument

..l'<t:

dl'~ll'r"-'\' bkg lO~nl 2929 S/N: 182597 rate t'.:nc: MDA 0.1 1 7.0 43-10-1 S/N: 188736 ex 0.364 cpm min d:-.~11 p ...... df(..,

Tech A Sign/ Date ":*"'-1-. 12/29/20Hi 46.7 1 76.2 Tech B Sign/ Date Cal Due Date: 5/13/2017 0 0.434 cpm min dp'11 p<:o~ ::i:of'i1 Page 3 Att. 4 Data Assessment F8300071