ML043640278

Maine Yankee Final Status Survey Release Record FR-0400 Forebay Survey Unit 2

ML043640278
Person / Time
Site:	Maine Yankee
Issue date:	12/20/2004
From:	Pillsbury G, Randall D B, Tozzie N Maine Yankee Atomic Power Co
To:	NRC/FSME
References
MN-04-060, RA-04-118 FR-0400-02, Rev 0
Download: ML043640278 (23)

Text

MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-0400 FOREBAY SURVEY UNIT 2 ,-. Date: Prepared By: C9t: °. Twxt 9jf-/3- 'N St FSS Engineer -Signature/12al-e .,dct4l .i/Printed Name Date: Reviewed By: MSS S-igalisfSignature SS S e Printed Name Reviewed By: /6/A, 4 4 Iiiidcpendeit Reviewcr -Signature Pted Name Date: Approved By: ___Date./_M 1up SS, A1r'P -Signature Printed Name MAINE YANKEE FINAL STATUS SURVEY RELEASE RECORD FR-0400 FOREBAY SURVEY UNIT 2 A. SURVEY UNIT DESCRIPTION Survey Unit 2 is located within Survey Area FR-0400, the Forebay. The Forebay is located south of the site radiologically Restricted Area at coordinates 407,250 N and 623,700 E (see map FRO400-SITE, Attachment 1). The Forebay is a large, rock-lined basin in which condenser cooling water collected prior to its release through the diffuser system out to the ocean. During plant operation, the Forebay/Diffuser system wvas the licensed discharge path for liquid, radiological effluent.

After plant shutdown, stop logs were set in place at the Forebay end of the diffuser to isolate the Forebay in order to prevent the release of Forebay sediment into the river during remediation activities.

Two earthen dikes make up the north-south running wvalls of the Forebay with concrete walls at the extreme north and south ends to support the circulating water and diffuser pipes. The dike walls form a V at the southern end of the Forebay (adjacent to Foxbird Island). The diffuser discharge pipes originate at the notch of the V. A concrete dam, or weir, runs in the east west direction at the northern end of the Forebay and creates a small, water-filled area called the sealpit. The sealpit maintained a water seal over the circulating water pipes to prevent loss of flow with tidal fluctuations.

Survey Unit 2 consists of the upper walls of the sealpit above an elevation of 4.5 feet. The sealpit wvalls consist of exposed ledge, gravel and native soil matrix materials.

The upper walls were normally above the water level of the sealpit. The Survey Unit has a surface area of approximately 1,475 m 2.B. SURVEY UNIT DESIGN INFORMATION The Forebay received the liquid radioactive discharges from the plant. It was known to have been contaminated to levels in excess of the release limits and extensive remediation activities including underwater dredging, underwater vacuuming, and dry surface vacuuming were performed.

Given the high probability of residual contamination, the Forebay was classified as Class 1.Revision 3 of the Maine Yankee License Termination Plan (LTP) ' states that the Forebay dose from residual radioactivity "is so insignificant and the probability so low that an individual would be able to successfully place a viable well within the Forebay, survey measurements of the Forebay surfaces including rip-rap will be limited".

As a result, the survey design for the Forebay is a reasonable approach to demonstrate compliance with the release criteria while not necessarily meeting all of the requirements for a "MARSSIM" survey.LTP, Revision 3 refers to the LTP submitted in October 2002 (Reference I) as amended by the MY's addenda of November 2002 (Reference 2). LTP, Revision 3 was approved by the NRC in February 2003 (Reference 3).FR-0400-02, Revision 0 Page 2 of 23 The survey unit design parameters are shown in Table 1. The values shown in this Table reflect those used for the design and implementation of the survey. Changes to several key parameters (i.e., DCGL and AF) occurred after the survey was complete.

These changes were used to evaluate the data, are discussed in Section HS, and shown in Table 2-2.Given a relative shift of 1.6, a minimum number of 17 direct samples were required for Survey Unit 2. The survey design was based on 20 samples. Nineteen points actually fell within the survey unit using a random start point and a square grid to determine sample locations.

These locations are presented on survey map FRO400-02a and FRO400-02b (Attachment 2). Direct measurements consisting of soil samples collected from required locations were analyzed With laboratory gamma spectroscopy instrumentation.

In accordance with the LTP, scans covering 100% of the 1475 m 2 area were required for this Class I survey unit. This was accomplished by use of an ISOCS in situ gamma spectroscopy system positioned 4.3 m from the surface to obtain an approximate 58 m field of view to a depth of 15 centimeters for each scan. A total of 52 measurements, located on a 6 m x 6 m grid pattern, were designed to achieve the 100% scan coverage.

Each grid was scanned with detection limits well below the design DCGLEMc. The investigation level was set equal to the design DCGLEMC. To avoid the safety hazard to personnel posed by the steep wvalls around the sealpit, a crane was used to lower the ISOCS into position.

The survey instruments used, their MDC values, and investigation levels are provided in Attachment 2.TABLE I SURVEY UNIT DESIGN PARAMETERS Survey Unit Design Criteria Basis Area 1,475 m'Based on an LBGR of 3.5 pCi/g, Number of Direct sigma 2 of 2.18 pCi/g, and a Measurements Required relative shift of 1.6.Type I = Type II = 0.05 Sample Area 73.8 m" 1,475 / 20 samples Sample Grid Spacing 8.55 m (73.8)v2 Area Factor (AF) 3.48 Forebay technical basis document Area__Factor______3.48_(Reference 4)Scan Survey Area 1475 m' -100% accessible areas Background N/A In situ gamma spec used Scan Investigation Level 24.4 pCi/g Co-60 -DCGLEMlc DCGL7 p~/g C-60Forebay technical basis document ADCGL 7 pCi/g Co-60 (Reference 4)Design DCGLENIC 24.4 pCi/g Co-60 Area Factor x DCGL 2 Sigma was determined using post remediation survey results.FR-0400-02, Revision 0 Page 3 of 23 C. SURVEY RESULTS Nineteen measurements wvere required by the survey instruction.

Eighteen were actually obtained due to the inaccessible location of sample R004. The direct measurement data are presented in Table 2 below. All direct measurements were belowv the DCGL.The survey wvas designed for 52 ISOCS measurements to provide 100% scan coverage.

Five of the measurement locations (ROOI through R005) were inaccessible due to the proximity of the waterline along the western boundary.

Forty-seven measurements were made with all results below the investigation level. Therefore, no investigations wvere required.TABLE 2 DIRECT MEASURMENTS

[ Sample Number l Cs-137 (pCilg) l Co-60 (pCi/g) J Utilized Values 3 FR0400-02-1-ROOlRS

-<2.76E-02

<3.61E-02 9.51E-04 FRO400-02-1-R002RS

-<3.39E-02

<3.21E-02 9.13-E04 FRO400-02-1-R003RS

-<2.77E-02

<2.81E-02 7.85E-04 FR0400 I -R004RS Not Accessible Not Accessible N/A FR0400-02-1-RO05RS

<5.85E-02

<6.88E-02 1.85E-03 lFRO400-02-1 -R006RS <2.98E-02

<2.94E-02 8.27E-04-FR0400-02-1-R007RS

<2.83E-02

<2.81E-02 7.89E-04 FR0400-02-1-R008RS 6.40E-02 + L.1E-02 1.13E-01 +/- 1.38E-02 2.82E-03 FR0400-02-1-R009SS

<6.77E-02

<9.02E-02 2.37E-03 FRO400-02-1-ROIOSS 3.70E-01 + 3.50E-02 <4.86E-02 3.68E-03 FR0400-02-1-ROlISS 2.55E-01 + 2.44E-02 <3.69E-02 2.60E-03 FRU400-02-1-RO12RS

<2.66E-02

<3.02E-02 8.20E-04 FR0400-02-1-RO13SS 3.38E-01 + 3.86E-02 4.64E-01 d3.45E-02 1.21E-02 FR0400-02-1-R014RS

<2.68E-02

<3.41E-02 9.03E-04 FR0400-02-1-ROI5RS

<5.18E-02

<5.05E-02 1.42E-03 FR0400-02-1-R016RS

<3.84E-02

<4.1 OE-02 1.13E-03 FR0400-02-1-R017SS 2.61E-01 +7.44E-02

<1.37E-01 4.73E-03 FRO400 1-RU18RS <2.531E-02

<2.49E-02 7.01 E-04 FRO400-02-1-R019RS

<2.76E-02

<2.8 1E-02 7.84E-04 Mean 9.77E-02 7.34E-02 J 2.23E-03 Median 3.62E-02 3.65E-02 1.04E-03 Standard Deviation 1.18E-01 1.03E-01 l 2.72E-03 Range l 2.53E-02 -3.70E-01 2.49E-02-4.64E-01 7.01E-04-1.21E-02

"<" indicates MDA value. Bold indicates positive detection value.3 These values were adjusted to account for the contamination depth used in the excavation scenario (60 cm).Refer to Section E for additional discussion.

FR-0400-02, Revision 0 Page 4 of 23 D. SURVEY UNIT INVESTIGATIONS PERFORMED AND RESULTS No investigations were required.E. SURVEY UNIT DATA ASSESSMENT The Forebay dike soil DCGL was developed assuming that a 2 foot (24 inch) band of soil contaminated at the DCGL exists underneath the rip-rap in the Forebay dikes. The 2 foot assumption was arbitrarily made based upon a minimum amount of data. In order to determine the actual extent of contamination within this band of soil, Maine Yankee performed extensive characterization using samples obtained from inclined core bores beneath the rip-rap as close to the rip-rap as possible.

Overall, the Forebay dike soil coring campaign showed that radiological contamination had not penetrated into the Forebay dikes beyond the rip-rap to any substantial depth (likely less than several inches).The ISOCS measurements of the Forebay dike soil through the rip-rap were geometrically configured such that the entire photon spectra was attributed to a contaminated soil band of 6 inches. Thus, this activity, attributed to a 6-inch band, should be divided by a factor of four in order to appropriately compare it to a DCGL which was developed assuming a 24-inch band of contaminated soil. This adjustment is also applicable to soil samples obtained at depths of 0" to 6" and is justified since the Forebay dike core boring campaign demonstrated that contamination had not penetrated into the Forebay dike beyond the rip-rap to any significant extent. The survey results for FR-0400 Survey Unit 2 were evaluated using this methodology.

An analysis of the direct sample measurement results, including the mean, median, standard deviation, and sample result range, are provided in Table 2. The sampling results yielded three samples with Cs-137 and two samples with both Cs-137 and Co-60. All samples were well below the Cs-137 and Co-60 DCGLs of 34.76 pCi/g and 12.01 pCi/g, respectively.

The maximum combined Cs-137 and Co-60 results were approximately 1.2% of the unitized DCGL.The ISOCS scan data was evaluated using the DCGLs stated above. All results were below the Cs-137 and Co-60 DCGL. Therefore, no investigations were required.

The results also ensure that there are no unevaluated areas exceeding the DCGLENIC values shown in Table 2-2.For illustrative purposes, as inidicated in LTP Section 5.9.3, a simplified general retrospective dose estimate can be calculated from the average residual contamination level by subtracting the established mean fallout Cs-137 background value of 0.19 pCi/g (Reference

5) for disturbed soil from the survey unit mean (0.098 pCi/g) yields a negative value which is equivalent to 0.0 mrem/y. Conversely, the annual dose contribution from Co-60 is determined by dividing the survey unit mean (0.07 pCi/g) by the DCGL and the factor of four as discussed above. This value is multiplied by the survey unit dose (9 mrem/y) assuming the survey unit mean is equal to the DCGL. The result is an annual dose of 0.014 mrern/y.This annual dose equivalent is based on the revised Forebay technical basis document (Reference

6) which shows that the excavation scenario DCGL equals 9 mrem/y (0.07/12.01 x V/ x 9 = 0.014 mrem/y).FR-0400-02, Revision 0 Page 5 of 23 F. ADDITIONAL DATA EVALUATION Attachment 4 provides additional data evaluation associated with this Survey Unit, including relevant statistical information.

Based on survey unit direct measurement data, this attachment provides the Sign Test Summary, Quantile Plot, Histogram, and Retrospective Power Curve.I. The Sign Test Summary provides an overall summary of design input and resulting calculated values used to determine the required number (N) of direct measurements (per LTP Section 5.4.2). The Sign Test Summary is a separate statistical analysis that also calculates the mean, median, and standard deviation of the direct measurements.

The critical value and the result of the Sign Test are provided in the Sign Test Summary table, as well as a listing of the key release criteria.

As is shown in the table, all of the key release criteria were clearly satisfied for the FSS of this survey unit.2. The Quantile Plot was generated from direct measurement data listed in Table 2. The data set and plot are consistent with expectations for a Class I survey unit. All of the measurements are well below the DCGL of 12 pCi/g Co-60 and 34.76 pCi/g Cs-I 37.3. A Histogram Plot was also developed based on the direct measurement values. This plot shows that the direct data -were essentially by a log-normal distribution with one outlier.4. A Retrospective Power Curve was constructed, based on FSS results. The curve shows that this survey unit having a mean residual activity at a small fraction of the DCGL has a high probability

("power")

of meeting the release criteria.

Thus, it can be concluded that 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 were met.G. CHANGES IN INITIAL SURVEY UNIT ASSUMPTIONS ON THE EXTENT OF RESIDUAL ACTIVITY The survey was designed as a Class I area. The FSS results were consistent with that classification.

Due to remediation activities, the source term appears to have increased Cs-137 to Co-60 ratios. This was addressed by including Cs-137 in the evaluation of the survey results. As discussed in Section E, a soil boring campaign demonstrated that the depth of contamination in the Forebay dikes was much less than the assumed value in the dose model. The data evaluation removed this conservatism.

The direct measurement sample standard deviation wvas less than the design sigma. Thus, a sufficient number of samples were obtained.FR-0400-02, Revision 0 Page 6 of 23 Il. LTP CHANGES SUBSEQUENT TO SURVEY UNIT FSS The FSS of Survey Unit 2 was designed and performed using the criteria of the approved Forebay Technical Basis Document (Reference

4) and LTP Revision 3 Addenda (Reference I and 2). Because of the FR 0400 EMC issues identified during the final data review (Reference Condition Report, CR 04-161), the soil excavation scenario was modified to increase the Forebay soil DCGL to a value which was equivalent to 90% (9 mrem/y) of the limit (10 mrem/y) allowed for soil outside the RA. This change raised the DCGLs for Co-60 and Cs-137 to 12.01 and 34.76 pCi/g respectively.

The soil area factors were applied to these values to derive the appropriate DCGLENIC.

These changes are documented in Reference 6.There were no other LTP changes that affected the survey design or results for the survey unit.l. CONCLUSION The FSS of this survey unit was designed based on the LTP designation as a Class I area.The survey design parameters are presented in Table 1. The required number of direct measurements was determined for the Sign Test in accordance with the LTP. As presented in Table 2, all direct measurements were less than the DCGL of 12 pCi/g Co-60 and 34 pCi/g Cs-I 37.A Sign Test Summary analysis demonstrated that the Sign Test criteria were satisfied.

The direct measurement sigma was determined to be less than that used for design, thus indicating that a sufficient number of samples was taken.The Retrospective Power Curve shown in Attachment 4 confirmed that sufficient samples were taken to support rejection of the null hypothesis, providing high confidence that the survey unit satisfied the release criteria and the data quality objectives were met. Attachment 4 also revealed that direct measurement data represented essentially a log-normal distribution, with variance consistent with expectations for a Class I survey unit.The scan survey design for this survey unit wvas developed in accordance with the Forebay Technical Basis Document with significant aspects of the design discussed in Section B and Table 1. Scanning resulted in no areas with activity above the investigation levels; therefore, no investigations were required.It is concluded that FRO400 Survey Unit 2 meets the release criteria of IOCFR20.1402 and the State of Maine enhanced criteria.FR-0400-02, Revision 0 Page 7 of 23 J. REFERENCES

1. Maine Yankee License Termination Plan, Revision 3, October 15,2002 2. Maine Yankee letter to the NRC, MN-02-06 1, dated November 26, 2002 3. NRC letter to Maine Yankee, dated February 28,2003 4. Maine Yankee letter to the NRC, MN-03-05 1, "Forebay Technical Basis Document," dated September 3, 2003 5. Approach for Dealing with Background Radioactivity for Maine Yankee Final Status Surveys, Attachment E to Maine Yankee Procedure PMP 6.7.8, FSS Data Processing and Reporting 6. Maine Yankee Calculation EC-041-01, Diffuser and Forebay Dose Assessment

7. Maine Yankee Calculation EC-003-04, Use of Canberra In Situ Object Counting System (ISOCS) for FSS Surveys FR-0400-02, Revision 0 Page 8 of 23 Attachment 1 Survey Unit Maps FR-0400-02, Revision 0 Page 9 of 23 Maine Yankee Ali akeDcmisoigPoetSryFomMap ID #: FRO400 SITE Decommissioning Team Afaine Yankee Decomnhissioning PIoject Surv Revised: 12/16104 Survey Type: 0 Remediation 0 Turnover U Final Status Survey Survey Area Name: Forebay Seal Pit Site Map SURVEY AREA (PARTIAL), FR 0400 FOXBIRD /ISLAND 623= OE eA 624.000 E z 0 z 0 0-z 2 Z 2 Z 2 SCALE I I MN D- ED N I 0 400 800 1200 Note: Grid based on Maine State Coordinate System (West Zone) NAD 1927 FR-0400-02, Revision 0 Page 10 of 23 Maine Yankee Maine Yankee Decommissioning Project Surv FormI Map ID #: FRO400 REF Decommissioning Team O TumoerDecomina siotang Iuivey Surve a m FRm Revised: 11A04P03 Survey Type: 5 investigation 5 Turnover X Final Status Survey ISurvey Area Name: FRO400 -FOREBAY SEAL PIT Seal Pit FSS Survev Unit Reference

1. 1 -3 BAILEY COVE CONC. ",!45DUHAMWU i_-- JSPILLWAv-.

-: --7-;EGEND:---- -- EDM or 1 AK> (\-- -N L-r-//I i. -.. --,- -- FDON--msa" (M CONTOWE OfUMAE BOTTIW Or GAW coNC anO& 8UO (\I., 'sj SURVEY UNIT 1 -FLAT SEDIMENTAREA' SURVEY UNIT 2 -LEDGE SLOPE(S)SURVEY UNIT 3 -CONCRETE t-7 S \N I-2 I'\s \8 r I. ;. 11 t ;,\ \\ 'I FOREBAY 2--/****R**N'"*\\\\I'1 SEAL PIT C 7 5- '.7 I-':- -" GRAPHIC SCALE:*- I:- L1 11' -U =L I I' )/7/XI.I ,~.4. , -'-Q. -FR-0400-02, Revision 0--. Page 11 of 23 I Maine Yankee aine D #- FIR 0400-02a Decommissioning Team I eRevised:

2-12-04 Survey Type: O Investigation O Turnover U Final Status Survey ISurvey Area Name: FR 0400, Forebay Seal Pit FRO400 SU2: Forebay Seal Pit East Bank Direct Points R001-R003 2Is I-CIRC WATER DISCHARGE K'Ledge (covered by Backfill)*10to1

• R002 4 Ledge 3RO3 p)0-I----- -At 12 6f7 CS IC 69 GRAPHIC SCALE: 0 10 I 20 30 I g 40 50(ft)FR-0400-02, Revision 0 Page 12 of 23 Survey Unit 2 Surface Area = 1475 sq-m L=8.55 N=20 r-=

Maine Yankee M P Map ID #: FRO400-02b Decommissioning Team Maine Yankee Deconimissioning Project Surve' Forin Revised: 12-16-04 Survey Type: O Investigation 0 Turnover W Final Status Survey lSurvey Area Name: Forebay Seal Pit West Slope-I FRO400 SU2: Forebay Seal Pit West Bank/Spillway Area Direct Points R004 -R019 0 2~~.t .........

... , .i Le8'I) _,_ --., -.--6 10 2 I 0 R019* R018 0 S017 DO Po Ledge* R014$; jQC Split-ISo Sample t

• S013 Ledge Ledge* R015

• R016 I..1 .Ledge Soil* R012 *so7J 1 1'1 16 18 20 s, 22 44 10 2 4 24 z y soil SrOgs N.--Ledge<

• ROOS It Soil solo.l k, IV 92 i.1~L 1;Ledge 0 R007\Ledge'.

• R006\ ROO\ Ledge\R005 \Ledge fi9t *R004 l11S urv X Surve-63 el 6;5 2 4 6 FR-0400-02, Revision 0 Page 13 of 23 8 10 ey Unit 2 Surface Area = 1475 sq-n L=8.55 N=20 Maine Yankee D P c F Map ID#: FR 0400-02c Decommissioning Team awIa e eonsinn ProectSurey rm IRevised:

2-12-04 Survey Type: O Remediation O Turnover

• Final Status Survey I Survey Area Name: FR 0400, Forebay Seal Pit FRO400 SU2: Forebay Seal Pit East Bank ISOCS Scan Locations

1. R045 -R052 0 1RO46 (\,_, R045 CIRC WATER DISCHARGE R047 0 R048 0 p R051 0 R049 R00 R052 R050 >--, 0 Ar 63 Alt 66 6?4f 69; FR-0400-02, Revision 0 f/ F Page 14 of 25 GRAPHIC SCALE: Q , 1,0 20 30 11 1 , 40 , 50(ft)PM -Survey Unit 2 Surface Area = 1475 sq-m East Slope = 220 sq-m West Slope/Spillway

= 1255 sq-m Maine Yankee .,... .Map ID #: FR0400-02d Decomain g Yankee Maine Yankee Decommissioning Project Survey Forin Revised: 2-12044 Decommissioning Team IRvsd -20 Survey Type: 0 Characterization 0 Turnover U Final Status Survey Survey Area Name: Forebay Seal Pit West Slope FRO400 SU2: Forebay Seal Pit West Bank/Spillway Area ,s, ISOCS Scan Locations

1. R001 -R044 Afj 4 1 0 RO*0 R0 _ RO06R00 R.OPI0 R07R008 0 RO14 R012 14 R01 4 16 RO15 R013 18 R016 2 ,D pRO19 R1 20 SRO20 R017 RS2 Rl O24RQj 22 60 R226 24 2 \R028 R027 R024 22 S R30.R032 RO51 204 R034 C -R35 7. _ \RO37\; //R003 SO3 RO38j /\ R033S t R0340 66 R041 R -5/6,7 e \ RO433t R043 /6 (FR-0400-02, Revision 0\ -Page 15 of 25 8 l Survey Unit 2 Surface Area = 1475 sq-n 10-East Slope = 220 sq-rn' West Slope/Spillway

= 1255 sq-r Attachment 2 Survey Unit Instrumentation FR-0400-02, Revision 0 Page 16of23 TABLE 2-4 INSTRUMENT INFORMATION Detector Design Scan MDC 605 See Table 2-2 1 7607__ _I See Table 2-2 IIPGe Detectors for Lab Analysis of Volumetric Samples I Detector Number I MDC (pCilg)T FSS-1 (HPGe) 0.05 -0.10 FSS-2 (HPGe) 0.05 -0.10 DET-2 (HPGe) 0.05 -0.10 TABLE 2-2 INSTRUMENT SCAN MDC AND COMPARISION WITH DCGLV AND DESIGN DCGLEr:sc Detector ISOCS J Comments ISOCS Sean MDC MDC < 7 pCi/g Co-60 DCGL 12 pCi/g Co-60 Reference 6 34.76 pCilg Cs-137 _ _ _ _ _ _ _ _ _ _ _Investigation Level 32 pCi/g Co-60137 < DCGLEMrC 1 6.8 pCi/g Co-60 DCGL x 1.4 (1.4 is the Design DCGLEMC 48.7 pCi/g Cs 137 actual AF for surface soil, 48.7p~ig Cs137LTP Table 6-12)FR-0400-02, Revision 0 Page 17of23 Attachment 3 Investigation Table (No Investigations Required)FR-0400-02, Revision 0 Page 18 of 23 Attachment 4 Statistical Data FR-0400-02, Revision 0 Page 19 of 23 Survey Package FRO400 Unit 2 Soil Sign Test Summary Survey Package: FRO400 Sealpit banks Survey Unit: 02 Evaluator:

DR DCGL,: 1 .OOE+OO DCGLemc: 1.40E+00 LBGR: 5.OOE-01 Sigma: 1.82E-01 (2.1 8 pCi/g 1 2pCi/g)Type I error: '0.05 Type II error: 0.05 Nuclide: UNITY Soil Type: N/A 1.645 ZI0: .:1.645 Sign p: 0.99379 Calculated Relative Shift: 2.71 Relative Shift Used: 4. .2.7 Uses 3.0 if Relative Shift is >3 N-Value: ' -12 N-Value+20%:-

,',: ,' -'__15 Number of Samples: t 18 Median: ,,, ;1 04E 03 Mean: :;> ' .i2 23E03 Net Sample Standard Deviation:

`.>.--,2.72E-03 Total Standard Deviation:

iZr E2 72E 03 SRSS Maximum: .e1 .21E-02__Adjusted N Value: C-. s , _ _ _ _ _ _ _ _ _ _ _ _ _S+ Value: .Critical Value: 2 Sign test results: , .Pass Sufficient samples collected:

iS' ' Pass Maximum value <DCGL.,: ; -VPaU Median value <DCGLN: P ';ass Mean value <DCGLg .a s __ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _Maximum value <DCGL,,,:

,:. -.ass Total Standard Deviation

<=Sigma. : a as_Criteria comparison results: , The survey unit passes all conditions:

X .-.-Fas_FRO400-SU2-SoiISIgn 11/30A34 12:56 PM FR-0400-02, Revision 0 Page 20 of 23 FR-0400 SU-2 Quantile Plot 0.01400 -0.01200 -11:0 a 0 cj o 0 W" x 0 0 0)N Ra*-1-4.'C., 0.01000 .- _. .-0.00800 0.00600 0.00400[* Activity (Unitized)

I Median (Unitized) 0.00200 0.00000._* _ _ _ __+ V9 0 25 50 75 100 Percent Page/Date/Time Database Variable One-Sample T-Test Report 2 12/16/04 5:18:01 AM C:\Program Files\NCSS97\FRO400SU2.SO C2 Plots Section Histogram of FR-0400. SU-2 4)0L E co E Z 15.II: a 4 J. --oX :.0.000 0oo04 ' ' O.oo .. X Activity (unitized) 0.611 ..0 214 FR-0400-02, Revision 0 Page 22 of 23 One-Sample T-Test Power Analysis 2 12116/04 5:19:02 AM Page/Date/Time Chart Section a)0-1.0 0.8 0.6 0.4 0.2 0.0 0.1 Retrospective Power Curve--- -------3 0!2 0!4 0.6 0.8 1.0 Survey Unit Mean (unitized)

FR-0400-02, Revision 0 Page 23 of 23