IR 05000344/2002002
| ML030380014 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 02/06/2003 |
| From: | Brockman K Division of Nuclear Materials Safety IV |
| To: | Quennoz S Portland General Electric Co |
| References | |
| +sispmjr200507, -RFPFR IR-02-004 | |
| Download: ML030380014 (64) | |
Text
February 6, 2003
SUBJECT:
ADDENDUM TO NRC INSPECTION REPORT 50-344/2002-004; RESULTS OF CONFIRMATORY SURVEY OF THE ISFSI-IMPACTED AREAS
Dear Mr. Quennoz:
January 2, 2003
SUBJECT:
FINAL REPORT-CONFIRMATORY SURVEY FOR THERISFSI IMPACTED AREAS, TROJAN NUCLEAR PLANT, RAINIER, OREGON
[DOCKET NO. 50-0344; RFTA NO. 02-0121
Dear Mr. Brown:
Enclosed is the final confirmatory survey report for the ISFSI Impacted Areas at the Trojan Nuclear Plant in Rainier, Oregon. The report describes the procedures and results of the confirmatory survey activities conducted October 7 through 10, 2002. U.S. Nuclear Regulatory Commission comments on the draft report have been incorporated.
Please contact me at (865) 576-5073 or Eric Abelquist at (865) 576-3740 if you require additional information.
Sincerely
" Timothy J. gttkus Survey Projects Manager Environmental Survey and Site Assessment Program TJV:ar Enclosure cc:
G. Purdy, NRC/NMSS/TWFN 7F27 E. Knox-Davin, NRC/NMSS/TWFN 8A23 J-C. Dehmel, NRC/NMSS/TWFN 7F27 E. Garcia, NRC/Region IV W. Beck, ORISE/ESSAP E. Abelquist, ORISE/ESSAP File/0832 P. 0. BOX 117, OAK RIDGE, TENNESSEE 37831-0117 Operated by 0akRidge Associated Universities for the U.S. Department of Energy
ORISE 02-1554 CONFIRMATORY SURVEY OF THE ISFSI IMPACTED AREAS TROJAN NUCLEAR PLANT RAINIER, OREGON Prepared by T. J. Vitkus and J. R. Morton Environmental Survey and Site Assessment Program Oak Ridge Institute for Science and Education Oak Ridge, Tennessee 37831-0117 Prepared for the U.S. Nuclear Regulatory Commission Division of Waste Management FINAL REPORT DECEMBER 2002 This report is based on work performed under an Interagency Agreement (NRC FIN No. J-5403)
between the U.S. Nuclear Regulatory Commission and the U.S. Department of Energy. Oak Ridge Institute for Science and Education performs complementary work under contract number DE-AC05 760R00033 withlthe U.S. Department of Energy.
y:essap\\project\\0832\\reports\\Final\\ISFSl ImpactedAreas Trojan Nuclear Plant - December 2002
TABLE OF CONTENTS PAGE L ist of Figures...............................................................
ii List of T ables................................................................
iv Abbreviations and Acronym s.....................................................
v Introduction and Site History.....................................................
Site D escription.............................
.................................
O bjectives...................................................................
D ocum ent R eview.............................................................
Procedures...................................................................
Sample Analysis and Data Interpretation............................................
Findings and R esults...........................................................
Comparison of Results with Release Criteria........................................
Sum m ary....................................................................
F igures......................................................................
T ables......................................................................
R eferences..................................................................
Appendices:
Appendix A:
Major Instrumentation Appendix B:
Survey and Analytical Procedures Trojan Nuclear Plant - December 2002 y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
LIST OF FIGURES PAGE FIGURE 1:
FIGURE 2:
FIGURE 3:
FIGURE 4:
FIGURE 5:
FIGURE 6:
FIGURE 7:
FIGURE 8:
FIGURE 9:
FIGURE 10:
FIGURE 11:
FIGURE 12:
FIGURE 13:
FIGURE 14:
FIGURE 15:
FIGURE 16:
FIGURE 17:
FIGURE 18:
Location of the Trojan Nuclear Plant...................................
Trojan Nuclear Plant - Plot Plan of ISFSI Impacted Areas.................
Turbine Building Interior North Wall Elevation 45' to 63' (TB/CB Walkway),
Survey Unit S02045B-Measurement and Sampling Locations.............
Maintenance Building Interior, Tool Room and Carpenter Shop, Survey Unit S03045A-Measurement and Sampling Locations....................... 12 Maintenance Building Interior, Machine Shop, Survey Unit S03045B--Measurement and Sampling Locations.......................
Fuel Building Interior, Crane Bay North Wall (East and West End) & East Wall, Survey Units S04045A&B-Measurement and Sampling Locations......... 14 RadWaste Annex Interior, Laundry Sort & Corridor Lower Walls and Floor, Survey Unit S04045L-Measurement and Sampling Locations.............
RadWaste Annex Interior, Compacting Area Lower Walls and Floor, Survey Unit S04045M-Measurement and Sampling Locations......................
Fuel Building Interior North Wall 93' Elevation, Survey Unit S04093B-Measurement and Sampling Locations.......................
Auxiliary Building Interior, Part of North Wall 93' Elevation, Survey Unit S05093A-Measurement and Sampling Locations.............
Turbine Building Exterior North Lower Wall, Survey Unit S 12045A-Measurement and Sampling Locations.......................
Maintenance Building Exterior Walls, Survey Unit S13045A-Measurement and Sampling Locations.......................
Fuel Building/RadWaste Annex Exterior North & West Lower Walls, Survey Unit S14045A-Measurement and Sampling Locations...................
Fuel Building/RadWaste Annex Exterior East Lower Walls, Survey Unit S 14045B-Measurement and Sampling Locations........................
Fuel Building Exterior West Upper Wall, Survey Unit S 14063A-Measurement and Sam pling Locations............................................
Auxiliary Building Exterior North Lower Wall, Survey Unit S 15045A-Measurement and Sampling Locations.......................
Auxiliary Building Exterior North Upper Wall, Survey Unit S 15063A-Measurement and Sampling Locations.......................
Control Building Exterior North- & East Lower Walls, Survey Unit S 16045A-Measurement and Sampling Locations.......................
Trojan Nuclear Plant - December 2002 ii y:essap\\proj ect\\0832\\reports\\Final\\ISFSI I mpactedAreas
LIST OF FIGURES (Continued)
FIGURE 19:
FIGURE 20:
FIGURE 21:
FIGURE 22:
FIGURE 23:
Control Building Exterior North Upper Wall, Survey Unit 16063A-Measurement and Sampling Locations....................
Control Building Exterior East Upper Wall, Survey Unit 16063A-Measurement and Sampling Locations....................
Chlorine Building Exterior Walls, Survey Unit
$32045B-Measurement and Sampling Locations...................
Materials Warehouse Exterior Walls, Survey Unit S37045A-Measurement and Sampling Locations...................
ISFSI Impacted Areas-Surveyed Grounds and Soil Sampling Locations December 2002 11v:essap\\project\\0832\\renorts\\Final\\ISFSI Imr Trombeja02n1Nucesalearec\\0P2lantts int SF t
l d*
ra PAGE S.... 27 S.... 28
.... 29 S.... 30 S.... 3 1 actedAreas Trojan Nuclear Plant -
ctedAi-eas
LIST OF TABLES PAGE TABLE 1:
Surface Activity Levels............................................
TABLE 2:
Selected Radionuclide Concentrations in Soil Samples by Gamma Spectroscopy.....................................
..............
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas iv Trojan Nuclear Plant - December 2002
ABBREVIATIONS AND ACRONYMS Ei Es BKG cm cm
cpm DCGL DOE dpm/100 cm2 EML ESSAP FSS ISFSI ITP LTP in2 MAPEP MARSSINM MDC MDCR MeV MWe MWt Nal NIST NRC NRIP ORISE PGE TNP instrument efficiency surface efficiency background centimeter square centimeter counts per minute derived concentration guideline level U.S. Department of Energy disintegrations per minute per 100 square centimeters Environmental Measurements Laboratory Environmental Survey and Site Assessment Program final status survey Independent Spent Fuel Storage Installation Intercomparison Testing Program license termination plan square meter Mixed Analyte Performance Evaluation Program Multi-Agency Radiation Survey and Site Investigation Manual minimum detectable concentration minimum detectable count rate million electron volts megawatt electric megawatt thermal sodium iodide National Institute of Standards and Technology U.S. Nuclear Regulatory Commission NIST Radiochemistry Intercomparison Program Oak Ridge Institute for Science and Education Portland General Electric Trojan Nuclear Plant y:essap\\project\\0832Vreports\\Fina]ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002 V
CONFIRMATORY SURVEY FOR THE ISFSI IMPACTED AREAS TROJAN NUCLEAR PLANT RAINIER, OREGON INTRODUCTION AND SITE HISTORY The Trojan Nuclear Plant (TNP), located in Rainier, Oregon, was jointly owned by the Portland General Electric (PGE), the City of Eugene through the Eugene Water and Electric Board, and Pacific Light/PacifiCorp and achieved initial criticality in December 1975. It began commercial operation in May 1976. The nuclear steam supply system was a four-loop pressurized water reactor that created an output rated at 3411 MWt, with an approximate net electrical output rating of 1130 MWe. After 17 years of operation, 14 fuel cycles, and approximately 3300 effective full-power days, the TNP was shut down for the final time on November 9, 1992 because of a steam generator tube leak precipitated by a failed sleeve. On January 27, 1993, PGE notified the U.S. Nuclear Regulatory Commission (NRC) of its decision to permanently cease power operations and decommission the facility (PGE 1999).
The decommissioning of the TNP was divided into two broad periods: a Transition Period and a Decontamination and Dismantlement Period. The Transition Period began with the plant shutdown in January of 1993 and will continue until the removal of the spent fuel from its temporary location in the spent fuel pool and movement to the Independent Spent Fuel Storage Installation (ISFSI). The Decontamination and Dismantlement Period and Transition Period are being performed concurrently.
Contaminated systems, components, and structural materials have been or are currently being decontaminated or removed. Final status surveys are being conducted in accordance with an NRC-approved License Termination Plan (LTP) and the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), and have been initiated on several surfaces and structures (NRC 1997).
The primary radionuclides of concern which were identified are mixed activation and fission products with Cs-137 as the predominant radionuclide.
PGE is planning to begin the transfer of the spent fuel to the ISFSI before the end of calendar year 2002. In preparation for this transfer, PGE has conducted the final status surveys (FSS) of some building exteriors and interiors. These surveys were performed prior to the spent fuel movement because the expected radiation "shine" from the spent fuel storage casks, once transferred to the ISFSI, will significantly increase the ambient radiation levels and affect the ability to otherwise conduct adequate FSSs in these areas. The areas PGE surveyed included the survey units near the y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002
ISFSI on the exterior of the Fuel, Auxiliary, Warehouse, and Maintenance buildings, and the interior of the Fuel and Auxiliary buildings.
The NRC Headquarters Office, Division of Waste Management requested that the Environmental Survey and Site Assessment Program (ESSAP) ofthe Oak Ridge Institute for Science and Education (ORISE) perform a confirmatory survey on selected building survey units and grounds surrounding the ISFSI.
SITE DESCRIPTION The TNP facility is located on 634 acres along the Columbia River in Columbia County, Oregon, approximately 42 miles north of Portland near the city of Rainier (Figure 1). The ISFSI, together with the Reactor Containment, Turbine, Control, Auxiliary, Fuel and other support buildings are located within the site's industrial area. The ISFSI is sited within the northeast quadrant of the industrial area and surrounded by an 8-foot high fence in the northeast portion and by a six-foot temporary fence around the remaining area (Figure 2). The buildings that are addressed by this report are to the south, east, and west of the ISFSI; a. hillside forms the north border with the Columbia River bank forming the eastern PGE site border.
OBJECTIVES The objectives of the confirmatory survey were to provide independent contractor field data reviews and radiological data for use by the NRC in evaluating the adequacy and accuracy of the licensee's procedures and final status survey results.
DOCUMENT REVIEW ESSAP and NRC personnel reviewed the licensee's available FSS documentation and data for adequacy and appropriateness, taking into account the LTP and MARSSIM considerations. At the time of the survey, PGE had not yet assembled the complete survey results for these areas into FSS survey packages. However, PGE provided the available field data to the NRC/ESSAP team to enable further planning of the confirmatory survey scope. PGE expects to issue the draft FSS reports either late this year or early in 2003.
y:essap\\project\\0832'reports\\Finai\\SFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
ACKNOWLEDGMENTS The authors would like to acknowledge the significant contributions of the following staff members:
FIELD STAFF T. L. Brown LABORATORY STAFF E. M. Ball R. D. Condra J. S. Cox W.P. Ivey CLERICAL STAFF D. K. Herrera K. L. Pond A. Ramsey ILLUSTRATORS T. L. Brown T. D. Herrera y:essap\\project\\0832\\reports\\Finai\\ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002
CONFIRMATORY SURVEY OF THE ISFSI IMPACTED AREAS TROJAN NUCLEAR PLANT RAINIER, OREGON Prepared by:
T. J. VitkuO S;ey Projects Manager Environmer*l Survey and Site Assessment Program Prepared by:
J. R.
oMn, ld Survey Team Leader Environmental Survey and Site Assessment Program Date:/2q a4 Date:/_i,*6/,4z.0 Reviewed by: 2 t
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o0 R. D. Condra, Laboratory Manager Environmental Survey and Site Assessment Program Reviewed by:..
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E A. T. Payne, Quality Mlanager Environmental Survey and Site Assessment Program late: /,\\ /I 71C2.-
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Date:
W. L. Beck, sociate Program Director Environmental Survey and Site Assessment Program Reviewed by:
-
- ,-Date:
0'z/oz E. W. Abetquist, ProgrA Director Environmental Survey and Site Assessment Program y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002
PROCEDURES Survey activities were conducted in accordance with a site-specific survey plan and the ORISE/ESSAP Survey Procedures and Quality Assurance Manuals (ORISE 2002a, 2000 and 2002b). Additional information concerning major instrumentation, sampling equipment, and survey and analytical procedures may be found in Appendices A and B.
The confirmatory surveys were performed on the exterior lower and upper wall survey units of the Auxiliary, Control, and Fuel buildings; and the exterior lower walls of the Turbine Building, RadWaste Annex, Materials Warehouse, Maintenance Building and Chlorine Building. Interior survey units included the RadWaste Annex, 45' and 93' levels of the Fuel Building, Fuel/Auxiliary Building wall gaps, and the 45' level of the Turbine Building. The table below provides the listing and classification of the selected confirmatory survey units.
Survey Unit ID Class Survey Unit ID Class S02045B S12045A
3 Turbine Bldg./interior, north wall Turbine Bldg./exterior, north lower wall S03045A S 13045A Maint. BldgJinterior, Tool Room and Carpenter
Maintenance Bldg.exterior walls Shop
_
S 14045A S03045B
Fuel Bldg. & RadWaste Annex/exterior,
Maint. Bldg./interior, Machine Shop north & west lower walls S 14045B S04045A
Fuel Bldg. & RadWaste Annex/exterior,
Fuel Bldg./interior, north wall, west end east lower walls S14063A S04045B
Fuel Bldg./exterior, north & west upper
Fuel Bldg./interior, north and east wall, east end walls S04045L S15045A RadWaste Annex/interior, Laundry Sort &
I Auxiliary Bldg./exterior, north lower
Corridor, lower walls and floor walls S04045M S15063A RadWaste Annex/interior, Compacting Area, I
Auxiliary Bldg./exterior, north upper
lower walls and floor walls y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
Survey Unit ID.,.,
Class Survey Unit ID I Class S04093B S 16045A
Control Bldg./exterior, north and east
Fuel BldgJinterior, north end walls lower walls S04093C Fuel/Auxiliary Bldg/Exterior Wall Gaps
C603 a3 Control Bldg./exterior, north and east upper walls S05093A S32045B
3 Auxiliary Bldg./north wall Chlorine Bldg./exterior, walls S37045A Materials Warehouse/exterior, walls
REFERENCE SYSTEM Measurements and sampling locations were referenced to either prominent building or land features or the existing PGE-established grid system and documented on facility drawings.
SURFACE SCANS Approximately 10 to 50 % of the accessible surfaces in each selected survey unit were scanned for beta activity using gas proportional or GM detectors. Particular attention was given to cracks and joints in the surfaces and other locations where material may have accumulated. Additionally, 100%
of the soil/gravel areas adjacent to the investigated building exterior walls were scanned for gamma radiation and paved areas were scanned for beta radiation, using Nal scintillation and gas proportional detectors, respectively. All detectors were coupled to ratemeters or ratemeter-scalers with audible indicators.
Locations where direct radiation levels were distinguishable from background or potentially exceeded the derived concentration guideline level (DCGL) for a given area were marked for further investigation.
SURFACE ACTIVITY MEASUREMENTS Direct measurements for total beta activity were performed at 73 locations on building exterior and interior surfaces. Measurement locations-with the exception of those measurements made within the Fuel/Auxiliary Building wall gaps-are on shown on Figures 3 through 22. All measurements were made using gas proportional or GM detectors coupled to portable ratemeter-scalers. Smear samplesfor-determining removable activity levels, were collected from direc-t-measurement locations y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
with the exception of the Fuel/Auxiliary Building wall gap locations. Direct measurements were not made on the grounds.
Normally, ESSAP procedures require collecting background direct measurements on a suitable reference material. The background count rates are then used in the survey unit measurement conversion to net surface activity levels. PGE has elected to conservatively represent final status survey results without a background correction. Therefore, with NRC concurrence, the decision was made to adapt the PGE approach for confirmatory measurements to permit a more direct comparison of the ESSAP and PGE results.
SOIL SAMPLING ESSAP collected two surface (0 to 15 cm) soil samples from soil areas surrounding the 1SFSI (Figure 23).
SAMPLE ANALYSIS AND DATA INTERPRETATION Samples and data were returned to ORISE's ESSAP laboratory in Oak Ridge, Tennessee for analysis and interpretation. Samples were analyzed in accordance with the ESSAP Laboratory Procedures Manual (ORISE 2002c). Smears were analyzed for gross alpha and gross beta activity using a low background gas proportional counter. Smear data and direct measurements for surface activity were converted to units of disintegrations per minute per 100 square centimeters (dpm/100 cm2). Soil samples were analyzed by gamma spectroscopy for gamma-emitting fission and activation products and results reported in units of picocuries per gram (pCi/g).
Confirmatory survey data were then compared with the site-specific derived concentration guideline levels (DCGLw).
The primary contaminants of concern for the TNP are beta-gamma emitters-fission and activation products-resulting from reactor operation. Cesium-137 and Co-60 have been identified during characterization as the predominant radionuclides present on surfaces within the Auxiliary Building. PGE's NRC-approved gross activity DCGL for interior surfaces of the Auxiliary Building is 7,500 beta dpm/100 cm2. PGE has not yet derived DCGLs for building exterior surfaces or for the interior of the Fuel Building. The DCGLs for soil will include the NRC screening DCGL of 3.8 pCi/g for Co-60 and 11.0 pCi/g for Cs-1 37, in addition to the application of the unityrule, and modification of these DCGLs to account for the presence of tritium within the soil.
The modified DCGLs were not finalized at the time of this report.
y:essap\\project\\0832\\reports\\Final\\lSFSt ImpactedAreas
Trojan Nuclear Plant - December 2002
FINDINGS AND RESULTS SURFACE SCANS Surface scans of the exterior and interior surfaces detected minor elevated beta radiation up to five times background levels in two interior locations within the clean laundry area of the RadWaste Annex and one interior location on the north wall of the Fuel Building Crane Bay. These locations were noted for investigative direct measurements (locations 31, 32, and 44 in Figures 6 and 7 and Table 1). Both of these were class 1 survey units. The beta and gamma radiation in the remaining scanned areas were comparable to background levels.
SURFACE ACTIVITY LEVELS Surface activity levels are provided in Table 1. The overall confirmatory measurement activity levels ranged from 620 to 6,500 dpm/100 cm2. The maximum activity levels were 2,300 dpm/l00 cm2 for class 3 survey units, 1,600 dpm/1 00 cm2 for class 2 survey units and 6,500 dpm/100 cm' for the class 1 survey units. Removable activity levels ranged from 0 to 5 dpm/l00 cm2 for gross alpha and from-5 to 30 dpmr/100 cm2 for gross beta.
RADIONUCLIDE CONCENTRATIONS IN SOIL There were no gamma-emitting fission or activation products identified in the soil samples where concentrations exceeded the minimum detectable concentrations (MDC) of the procedure. The maximum individual MDC was 0.23 pCi/g. The results for selected radionuclides, consisting of Co 60 and Cs-137, are provided in Table 2.
COMPARISON OF RESULTS WITH RELEASE CRITERIA Because finalization of approved DCGLs has not been completed for all areas, ESSAP's evaluation of confirmatory survey results does not include a comparative analysis with that of the DCGLs. This evaluation may be conducted at a later time once PGE presents its formal results and NRC authorizes ESSAP to revise this draft report to accommodate this evaluation. A comparison of the confirmatory minimum and maximum activity level ranges for each survey unit was made with those from the preliminary PGE random systematic measurement results. This comparison showed agreement between the two data sets. Furthermore, the confirmatory surface activity levels were also consistent with each survey unit's classification.
y:essap\\project\\0832\\reports\\Final\\lSFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
SUMMARY At the request of the Nuclear Regulatory Commission's Headquarters Office, the Environmental Survey and Site Assessment Program of the Oak Ridge Institute for Science and Education conducted a confirmatory survey of the ISFSI Impacted Areas at the Trojan Nuclear Plant in Rainier, Oregon.
Confirmatory activities performed during the period October 7 through 10, 2002 included reviews of PGE final status survey data, confirmatory surface scans, direct measurements, sampling for removable contamination, and soil sampling and analysis.
The confirmatory surveys did not identify any residual surface activity distinguishable from background on the exterior of surveyed buildings or the area grounds. Three locations of elevated beta radiation were noted on interior structural class 1 survey units in the RadWaste Annex and the Fuel Building Crane Bay. The analytical results for soil samples did not identify any residual TNP derived gamma-emitting fission or activation products. Comparative measurement results again showed general agreement.
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
FIGURES y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002
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Trojan Nuclear Plant - December 2002
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Trojan Nuclear Plant - December 2002
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NORTH WALL (East Section)
NORTH WALL (West Section)
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- " SINGLE-POINT D
SURVEYED AREA NOT TO SCALE FIGURE 16: Auxiliary Building Exterior North Lower Wall, Survey Unit S15045A Measurement and-Sampling Locations y:essap\\project\\0832\\-eports\\Finat\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
832-015 (1)
El. 118'
El. 63 MEASUREMENT/SAMPLING LOCATIONS 0# SINGLE-POINT
[]SURVEYED AREA NOT TO SCALE FIGURE 17: Auxiliary Building Exterior North Upper Wall, Survey Unit S15063A I.........
.Measurement and -Sampling Locations-y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas i~i~i~iii~i~ii~i
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Trojan Nuclear Plant - Decemlser 2002
NORTH WALL EAST WALL MEASUMENIT/SAMIPLING LOCATIONS 0* SINGLE-POINT
[]SURVEYED AREA NOT TO SCALE FIGURE 18: Control Building Exterior North and East Lower Walls, Survey Unit S16045A
...-..-..
Measurement and Sampling Locations y:essap\\project\\0832\\reports\\Final\\lSFSI ImpactedAreas 832-016 (1)
832-016 (1)
Trojan Nuclear Plant - December 2002
832-017 (2)
i9...
i~i*~ii*ii MEASUREMENT/SAMPLING LOCATIONS SINGLE-POINT
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SURVEYED AREA NOT TO SCALE FIGURE 19:
Control Building Exterior North Upper Wall, Survey Unit S 16063A Measurement and Sampling Locations y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas El. 63'
...........
Trojan Nuclear Plant - December 2002
El. 188'
'DOOR'
El. 63'
MEASUREMENT/SAMPLING LOCATIONS 0* SINGLE-POINT SURVEYED AREA NOT TO SCALE FIGURE 20: Control Building Exterior East Upper Wall, Survey Unit S 16063A
...
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-- Measurement-and-Sampling-Locations.
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas 832-018 (1)
Trojan Nuclear Plant - December 2002
832-021 (1)
ROLL-UP DOOR r
rw-r ROLL-UP NORTH WALL SOUTH WALL 1I EAST WALL MEASUREMENT/SAMPLING LOCATIONS S# SINGLE-POINT
[SURVEYED AREA NOT TO SCALE FIGURE 21: Chlorine Building Exterior Walls, Survey Unit S32045B
Measurement and-Sampling Locations -....
..
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas ROLL-UP DOOR
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-
.
Trojan Nuclear Plant - December 2002
832-022 (1)
FIGURE 22: Materials Warehouse Exterior Walls, Survey Unit S37045A S..
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Trojan Nuclear Plant - December 2002
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TABLES y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002
TABLE 1 SURFACE ACTIVITY LEVELS ISFSI IMPACTED AREAS TROJAN NUCLEAR PLANT RANIER, OREGON Total Beta Activity (dpm/100 cm2)
Removable Activity (dpm/100 cm2)
Alpha Beta Turbine Building/Interior, TB/CB Walkway - S02045B class 3 North Wall
620
-1 North Wall
970
1 Maintenance Building/Interior, Tool Room and Carpenter Shop - S03045A class 2 East Wall
970
-1 Floor
1300
3 West Wall
920
6 Floor
1300
-1 Floor
1300
3 Maintenance Building/Interior, Machine Shop - S03054B class 3 Floor
1300
-4 West Wall
930
3 Floor
1300
1 Floor
1300
-2 Fuel Building/Interior, Crane Bay - S04045A class 1 North Wall
6500
30 North Wall
1600
-2 North Wall
620
4 Fuel Building/Interior, Crane Bay - S040045B class 2 North Wall
1100
2 North Wall
810
-5 East Wall
760
2 RadWaste Annex/Interior, Clean Laundry & Corridor - S04045L class 1 FloorQr-Grid 259 31.570_
-3 y:essap\\project\\0832\\reports\\Final]\\ISFS ImpactedAreas
33 Trojan Nuclear Plant - December 2002
TABLE 1 (Continued)
SURFACE ACTIVITY LEVELS ISFSI IMPACTED AREAS TROJAN NUCLEAR PLAN RANIER, OREGON
Total Beta Activity (dpm/100cm2)
Removable Activity (dpm/100cm2)
Alpha i
Beta RadWaste Annex/Interior, Clean Laundry & Corridor - S04045L class 1 (continued)
Floor @ Drain-Grid 266
West Wall
North Wall
South Wall
6400 940 960 870
! RadWaste Annex/Interior, Waste Compacting - S04045M class 1 Floor - Grid 174
1500 North Wall
1100 Floor - Grid 146
1100 North Wall
980
3
-5
14
3 Fuel Building/Interior - S04093B class 2 North Wall
1600
15 North Wall
740
3 Fuel/Auxiliary Building Wall Gaps - S04093C class 3'
Horizontal I-Beam N/A 1200
---*C East Wall 97'
I-Cross Beam - East Wall 97'
N/A 1300
......
Horizontal Main Beam N/A 1200 North Wall 97'
Horizontal I-Beam N/A 930
--
North Wall 97'
Top of Inner Block Wall-N/A 1700 West 97'
Concrete Ledge - West 93'
N/A 1400
--
Outer Wall-North 93'
N/k 1200 y:essap\\project\\0832\\reports\\Fina[\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
TABLE 1 (Continued)
SURFACE ACTIVITY LEVELS ISFSI IMPACTED AREAS TROJAN NUCLEAR PLAN RANIER, OREGON I
Removable Activity Survey Unit/Area Total Beta Activity Locationa (dpm/100cm2)
_________
_ IAlpha Beta Fuel/Auxiliary Building Wall Gaps - S04093C class 3' (continued)
Inner Wall - North 93'
N/A 1800 Auxiliary Building/Interior - S05093A class 2 North Wall
780
-2 North Wall
740
4 North Wall
660
-4 Turbine Building/Exterior - S12045A class 3 North Wall
1100
-2 North Wall
1200
-3 North Wall
960
-2 Maintenance Building/Exterior - S13045A class 3 West Wall
2300
5 North Wall
830
-1 West Wall
1200
2 West Wall
1300
-2 East Wall
1600
-1 South Wall
820
-3 Fuel Building/RadWaste Annex/Exterior ' S14045A/B & S14063A class 3 West Wall
830
5 West Wall
1100
-4 North Wall
1200
-1 East Wall
1300
-3 East Wall
1500
1 Trojan Nuclear Plant - December 2002
y:essap\\project\\0832\\repor ts\\Ffinal\\lS FSI I mpactedAreas
TABLE 1 (Continued)
SURFACE ACTIVITY LEVELS ISFSI IMPACTED AREAS TROJAN NUCLEAR PLAN RANIER, OREGON Total Beta Activity (dpm/100cm2)
Removable Activity (dpm/100cm2)
Alpha Beta Auxiliary Building/Exterior - S15045A & S15063A class 3 North Wall
1300
3 North Wall
1200
-2 North Wall
1500
-2 North Wall
720
-3 North Wall
710
2 Control Building/Exterior - S16045A & S16063A class 3 North Wall
830
-1 North Wall
1000
-I East Wall
890
-3 North Wall
1100
-4 North Wall
1400
-1 East Wall
1100
1 Chlorine Building/Exterior - S32045B class 3 West Wall
1700
-2 North Wall
1300
2 West Wall
2100
3 South Wall
2100
-1 y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
36 Trojan Nuclear Plant - December 2002
TABLE 1 (Continued)
SURFACE ACTIVITY LEVELS ISFSI IMPACTED AREAS TROJAN NUCLEAR PLAN RANIER, OREGON Removable Activity Survey Unit/Area Locationa Total Beta Activity (dpm/100cm2)
(dpm/100cm2 )
Alpha Beta Material Warehouse - S037045A class 3 East Wall
1400
-4 East Wall
1400
6 East Wall
1400
-2 North Wall
1400
3 South Wall
1300
-4
'Refer to Figures 3 through 22.
'No Figure.
'--- = Smear not collected.
y:essap\\project\\0832\\reports\\Final\\ISFSl ImpactedAreas
.Trojan Nuclear Plant - December 2002
TABLE 2 SELECTED RADIONUCLIDE CONCENTRATIONS IN SOIL SAMPLES BY GAMMA SPECTROSCOPY TROJAN NUCLEAR PLANT RANIER, OREGON Radionuclide Concentrations (pCi/g)
Co-60 Cs-137 S832S001 0.00 +/- 0.0 2 b,c 0.00 +/- 0.01 832S002 0.01 +/- 0.02 0.00 +/- 0.01
'Refer to Figure 23.
bZero value due to rounding.
'Uncertainties represent the 95% confidence interval, based on total propagated uncertainties.
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
REFERENCES Portland General Electric (PGE). Trojan Nuclear Plant License Termination Plan, Rainier, Oregon.
August 5, 1999.
Oak Ridge Institute for Science and Education (ORISE).
Survey Procedures Manual for the Environmental Survey and Site Assessment Program. Oak Ridge, TN; September 2000.
Oak Ridge Institute for Science and Education. Confirmatory Survey Plan for the ISFSI Impacted Areas, Trojan NuclearPlant, Rainier, Oregon [Docket No. 50-0344; RFTA No. 02-012]. OakRidge, TN; September 30, 2002a.
Oak Ridge Institute for Science and Education. Quality Assurance Manual for the Environmental Survey and Site Assessment Program. Oak Ridge, TN; April 2002b.
Oak Ridge Institute for Science and Education. Laboratory Procedures Manual for the Environmental Survey and Site Assessment Program. Oak Ridge, TN; January 2002c.
U.S. Nuclear Regulatory Commission (NRC). Multi-AgencyRadiation Survey and Site Investigation Manual (MARSSIM). Washington, DC; NIJREG-1575; December 1997.
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
Trojan Nuclear Plant - December 2002
APPENDIX A MAJOR INSTRUMENTATION Trojan Nuclear Plant - December 2002 y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas
APPENDIX A MAJOR INSTRUMENTATION The display of a specific product is not to be construed as an endorsement of the product or its manufacturer by the authors or their employer.
SCANNING INSTRUMENT/DETECTOR COMBINATIONS Beta Ludlum Floor Monitor Model 239-1 combined with Ludlum Ratemeter-Scaler Model 2221 coupled to Ludlum Gas Proportional Detector Model 43-37, Physical Area: 550 cm2 (Ludlum Measurements, Inc., Sweetwater, TX)
Ludlum Ratemeter-Scaler Model 2221 coupled to Ludlum Gas Proportional Detector Model 43-68, Physical Area: 126 cm2 (Ludlum Measurements, Inc., Sweetwater, TX)
Beta-Gamma Ludlum Ratemeter-Scaler Model 2221 coupled to Eberline GM Detector Model HP-260, Physical Area: 20 cm 2 (Eberline, Santa Fe, NM)
Gamma Eberline Pulse Ratemeter Model PRM-6 (Eberline, Santa Fe, NM)
coupled to Victoreen Nal Scintillation Detector Model 489-55, Crystal: 3.2 cm x 3.8 cm (Victoreen, Cleveland, OH)
DIRECT MEASUREMENT INSTRUMENT/DETECTOR COMBINATIONS Beta Ludlum Ratemeter-Scaler Model 2221 coupled to Ludlum Gas Proportional Detector Model 43-68, Physical Area: 126 cm2 (Ludlum Measurements, Inc., Sweetwater, TX)
Ludlum Ratemeter-Scaler Model 2221 coupled to Eberline GM Detector Model HP-260, Physical Area: 20 cm2 (Eberline, Santa Fe, NM)
y:essap\\project\\0832\\reports\\Final\\ISFSl ImpactedAreas A-2 Trojan Nuclear Plant - December 2002
LABORATORY ANALYTICAL INSTRUMENTATION Low Background Gas Proportional Counter Model LB-5100-W (Tennelec/Canberra, Meriden, CT)
High Purity Extended Range Intrinsic Detector CANBERRA Model No: ERVDS30-25195 (Canberra, Meriden, CT)
Used in conjunction with:
Lead Shield Model G-1 1 (Nuclear Lead, Oak Ridge, TN) and Multichannel Analyzer DEC ALPHA Workstation (Canberra, Meriden, CT)
High Purity Extended Range Intrinsic Detector CANBERRA Model No: ERVDS30-25195 (Canberra, Meriden, CT)
Used in conjunction with:
Lead Shield Model G-11 (Nuclear Lead, Oak Ridge, TN) and Multichannel Analyzer DEC ALPHA Workstation (Canberra, Meriden, CT)
High Purity Extended Range Intrinsic Detector Model No. GMX-45200-5 (EG&G ORTEC, OAK RIDGE, TN)
used in conjunction with:
Lead Shield Model SPG-16-K8 (Nuclear Data)
Multichannel Analyzer DEC ALPHA Workstation (Canberra, Meriden, CT)
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas A-3 Trojan Nuclear Plant - December 2002
APPENDIX B SURVEY AND ANALYTICAL PROCEDURES y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas Trojan Nuclear Plant - December 2002
APPENDIX B SURVEY AND ANALYTICAL PROCEDURES PROJECT HEALTH AND SAFETY All survey and laboratory activities were conducted in accordance with ORISE health and safety and radiation protection procedures. Additionally, PGE provided general site training, fall protection training, and lift training.
CALIBRATION AND QUALITY ASSURANCE Calibration of all field and laboratory instrumentation was based on standards/sources, traceable to NIST, when such standards/sources were available. In cases where theywere not available, standards of an industry-recognized organization were used.
Analytical and field survey activities were conducted in accordance with procedures from the following documents of the Environmental Survey and Site Assessment Program:
"*
Survey Procedures Manual, (September 2000)
"*
Laboratory Procedures Manual, (January 2002)
"*
Quality Assurance Manual, (April 2002)
The procedures contained in these manuals were developed to meet the requirements of Department of Energy (DOE) Order 414. 1A and the U.S. Nuclear Regulatory Commission Quality Assurance Manual for the Office of Nuclear Material Safety and Safeguards and contain measures to assess processes during their performance.
Quality control procedures include:
"*
Daily instrument background and check-source measurements to confirm that equipment operation is within acceptable statistical fluctuations.
"*
Participation in MAPEP, NRIP, ITP, and EML Laboratory Quality Assurance Programs.
- Training and certification of all individuals performing procedures.
- Periodic internal and external audits.
y:essap\\project\\0832\\reports\\Final\\lSFSI ImpactedAreas B-2 Trojan Nuclear Plant - December 2002
Detectors used for assessing surface activity were calibrated in accordance with ISO-7503'
recommendations.
The total efficiency (Etoa) was determined for each instrument/detector combination and consisted of the product of the 27c instrument efficiency (E1) and surface efficiency (Es): Etotal = Ei X Eý The 2ni instrument efficiency factor (E1) was 0.40 for the gas proportional detectors and 0.18 for the GM detectors calibrated to Tc-99.
The surface efficiency factor (Es) was 0.5. The total beta efficiency factor for gas proportional detectors was 0.20 and was 0.09 for the GM detectors. Tc-99 was selected as the calibration source as it provides a conservative representation of the beta energy distribution of the radionuclide mixture reported for the site, consisting of predominantly Cs-137.
ISO-7503' recommends an E. of 0.25 for beta emitters with a maximum energy of less than 0.4 MeV and an E. of 0.5 for maximum beta energies greater than 0.4 MeV. Although the beta energy of the calibration source is less than the 0.4 MeV threshold, the estimated beta energy of the mixture, approximately 0.440 MeV, justifies the use of 0.5 for the E.
SURVEY PROCEDURES Surface Scans Surface scans were performed by passing the detectors slowly over the surface; the distance between the detector and the surface was maintained at a minimum - nominally about 1 cm. A large surface area, gas proportional floor monitor and a NaJ scintillation detector were used to scan the paved surfaces and gravel/soil areas, respectively, of the surveyed areas. Wall surfaces were scanned using small area (20 cm2 or 126 cm 2) hand-held detectors. Identification of elevated levels was based on increases in the audible signal from the recording and/or indicating instrument.
Scan minimum detectable concentrations (MDCs) were estimated using the calculational approach described in NUREG-1507.2 The MDCScan is a function of many variables, including the background level. Alpha plus beta background levels averaged 250 cpm for the hand-held gas proportional detector. Additional parameters selected for the calculation of MDC*, included a one-second observation interval, a specified level ofperformance at the first scanning stage of 95% true positive rate and 25% false positive rate, which yields a d' value of 2.32 (NUREG-1507, Table 6.1), and a
'International Standard. ISO 7503-1, Evaluation of Surface Contamination - Part 1: Beta-emitters (maximum beta energy greater than 0.15 MeV) and alpha-emitters. August 1, 1988.
...NUREG-l507.
MinimumDetectable CocentratioinsWithTyypicatIadiation Survey Instruments for Various Contaminants and Field Conditions. US Nuclear Regulatory Commission. Washington, DC; June 1998.
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas B-3 Trojan Nuclear Plant - December 2002
surveyor efficiency of 0.5. The instrument efficiency (Ei) for the hand-held gas proportional detectors calibrated to Tc-99 was 0.40. To illustrate an example for the hand-held gas proportional detectors, the minimum detectable count rate (MDCR) and scan MDC can be calculated as follows:
si = d'Vi = 4.7 counts MDCR = (si)(60 )i =284 cpm where:
si =minimum number of net source counts in the interval bi = number of background counts in the observation interval (i) = (250 counts minute-') (i seconds/60 seconds minute')
The MDCscan is calculated assuming a surface efficiency (E) of 0.5 and in this example an instrument efficiency (Ei) of 0.40:
MDC,,
7 MDCR
= 2,000 dpm /100 cm2 The MDC for the floor monitor was approximately 4,400 dpm/100 cm2.
Scan MDCs for the NaI scintillation detector for Cs-137 and Co-60 would approximate those contained inNUREG-1507. Respectively, these MDCs are 5.8 and 10.4 pCi/g for Co-60 and Cs-137.
Surface Activity Measurements Measurements of total beta surface activity levels were performed using gas proportional detectors with portable ratemeter-scalers. Surface activity measurements were made on steel and concrete.
Count rates (cpm), which were integrated over one minute with the detector held in a static position, were converted to activity levels (dpm/ 100 cm2) by dividing the gross rate by the total efficiency (E*xE)
and correcting for the active area of the detector. No background correction was made in order to accurately compare ESSAP results with PGE's, who has elected to not subtract a material specific background.
y:essap\\project\\0832\\reports\\Final\\ISFSI ImpactedAreas B-4 Trojan Nuclear Plant - December 2002
The minimum detectable concentrations (MDC) were 300 and 310 dpm/100 cm2 for the gas proportional detectors and 1900 dpm/100 cm2 for the GM detector. The physical surface area assessed was 126 cm2 the gas proportional detectors and 20 cm2 for the GM detector.
Removable Activity Measurements Removable gross alpha and gross beta activity levels were determined using numbered filter paper disks, 47 mm in diameter. Moderate pressure was applied to the smear and approximately 100 cm 2 of the surface was wiped. Smears were placed in labeled envelopes with the location and other pertinent information recorded.
RADIOLOGICAL ANALYSIS Detection Limits Detection limits, referred to as MDCs, were based on 3 plus 4.65 times the standard deviation of the background count [3 + (4.65,JBKG)]. Because of variations in background levels, measurement efficiencies, and contributions from other radionuclides in samples, the detection limits differ from sample to sample and instrument to instrument.
Gross Alpha/Beta Smears were counted for two minutes on a low-background gas proportional system for gross alpha and beta activity. The MDCs of the procedure were 9 dpm/100 cm 2 and 15 dpm/100 cm2 for gross alpha and gross beta, respectively.
Gamma Spectroscopy Soil samples were dried, homogenized as necessary, and a portion sealed in 0.5-liter Marinelli beakers or other appropriate container. The quantity placed in the beaker was chosen to reproduce the calibrated counting geometry. Net material weights were determined and the samples counted using intrinsic germanium detectors coupled to a pulse height analyzer system. Background and Compton stripping, peak search, peak identification, and concentration calculations were performed using the computer capabilities inherent in the analyzer system. All photopeaks associated with the y:essap\\project\\0832\\reports\\Final\\lSFSI ImpactedAreas B-5 Trojan Nuclear Plant - December 2002
radionuclides of concern were reviewed for consistency of activity. Photopeaks used for determining the activities ofradionuclides of concern and the typical associated MDCs for a one hour count time were:
Radionuclide Ag-l11m Ba-133 Ce-144 Co-57 Co-60 Cs-134 Cs-137 Eu-152 Eu-154 Eu-155 Mn-54 Na-22 Sb-125 Zn-65 MDC soil (pOi/1)
Photopeak 0.658 MeV 0.356 MeV 0.134 MeV 0.122 MeV 1.173 MeV 0.796 MeV 0.662 MeV 0.344 MeV 0.723 MeV 0.105 MeV 0.834 MeV 1.275 MeV 0.428 MeV 1. 115 MeV 0.05 0.04 0.22 0.03 0.05 0.06 0.05 0.11 0.13 0.07 0.03 0.06 0.07 0.17 Spectra were also reviewed for other identifiable photopeaks.
y:essap\\project\\0832\\reports\\Finai\\ISFSI ImpactedAreas B-6 Trojan Nuclear Plant - December 2002