ML011060191

Request to Release Certain Portions of General Atomics Facility to Unrestricted Use and Delete Them from License: Namley, the Building 2 Service Corridor Drain Line Trench

ML011060191
Person / Time
Site:	07000734
Issue date:	04/04/2001
From:	Asmussen K General Atomics
To:	Adams M, Rogus R NRC/NMSS/FCSS, State of CA, Dept of Health Services
References
-RFPFR, 696/CAL- 3353
Download: ML011060191 (32)

Text

+ GENERAL ATOMICS April 4, 2001 696/CAL-3353 VIA EXPRESS MAIL SERVICE Ms. Mary Adams (in Duplicate)

Licensing Section 1/Licensing Branch Division of Fuel Cycle Safety and Safeguards, NMSS U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Docket No.70-734; SNM-696: Request to Release Certain Portions of General Atomics' Facility to Unrestricted Use and Delete them from License: Namely, the Building 2 Service Corridor Drain Line Trench and ATTN: Dr. Ronald Rogus (in Duplicate)

State of California Department of Health Services Radiologic Health Branch Mail Stop 178 601 North 7th Street Sacramento, CA 95814-0208

Subject:

Radioactive Materials License No. 0145-37:

Request to Release Certain Portions of General Atomics' Facility to Unrestricted Use and Delete them from License: Namely, the Building 2 Service Corridor Drain Line Trench

Dear Ms. Adams and Dr. Rogus:

As you are aware, General Atomics (GA) is continuing its efforts to decontaminate, as appropriate, and obtain the release to unrestricted use of selected facilities and land areas on its site. Most recently, GA completed the Final Radiological Survey of a trench inside the service corridor of Building 2. The trench was created during removal of the underground drain lines associated with the sewerage system within Building 2. The resulting sewer line trench runs though the entire service corridor (see attached figure) for a total length of approximately 1,030 feet.

Some of these sewer drain lines were known to be radioactively contaminated. Because of this, and the fact that the lines were mainly cast iron pipes which were deteriorating, it was decided to conservatively assume that the drain lines were contaminated, and to remove and replace all of the drain lines with new, plastic pipe. The cast iron pipes which were removed in sections at a time, are being disposed of as low level radioactive waste.

During the removal of the drain lines, the concrete floor was cut in sections and the concrete and top soil removed in order to expose the underground drain lines. The concrete and soil removed were placed in GA's Temporary Soil Staging Area, Bins T-48 and T-31, respectively.

The concrete and soil in these bins were subsequently surveyed and released by the NRC to unrestricted use by letter dated November 16, 2000 signed by Ms. Mary Adams.

Radiation measurements inside the trench were taken on both the bottom and the sides of the trench. Additionally, a total of 104 soil samples were collected from the bottom of the 3550 GENERAL ATOMICS COURT, SAN DIEGO, CA 92121-1122 P0 BOX 85608, SAN DIEGO, CA 92186-5608 (8

W 455-380

)

Mary Adams, U.S. NRC/Ronald Rogus, State April 4, 2001 696/CAL-3353 Page 2 trench and analyzed by gamma spectroscopy. These results are summarized in the enclosed report titled, "General Atomics' Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench," dated March 2001. The results of these surveys and analyses demonstrate that this trench meets the NRC-and State-approved criteria for release to unrestricted use.

The drain line trench is currently covered with large plywood boards. However, due to safety and other concerns, GA would like to backfill the trench with clean soil and pour a new concrete floor as soon as possible. The remainder of the Building 2 service corridor will be the subject of a future separate release request.

Accordingly, GA hereby requests that the NRC release the trench to unrestricted use and allow GA backfill the trench as soon as possible. GA believes that it is appropriate for the NRC to take the lead regulatory oversight role for the release of GA's Building 2 service corridor, including conducting confirmatory surveys, (if deemed appropriate), for the following reasons:

(1)

The NRC took the lead on the last groups of labs released in Building 2, (2)

NRC licensed materials were used in a many of the labs in Building 2, (3)

The NRC took the lead in surveying and releasing the concrete and soil which came from this trench (SSA Bins T-31 and T-48), and (4)

The NRC has already surveyed other trenches in Building 2 (e.g., three trenches which were lead outs from the main sewer drain lines were surveyed and sampled by NRC; which allowed GA to backfill those trenches).

If you should have any questions regarding this information, please contact Laura Q.

Gonzales at (858) 455-2758, or me at (858) 455-2823. Your assistance in responding to our request is very much appreciated.

Very truly yours, Keith E. Asmussen, Ph.D., Director Licensing, Safety and Nuclear Compliance Attached Figure: Building 2 Service Corridor Drain Line Trench

Enclosure:

Report titled: "General Atomics' Final Radiological Survey Report for Building 2 Service Corridor Drain Line Trench," dated March 2001.

cc:

Dr. D. Blair Spitzberg, Chief, NMSS Branch 3, Region IV Mr. Wayne L. Britz, Fuel Cycle Inspector, NRC Region IV Mr. Emilio Garcia, Fuel Cycle Inspector, NRC Region IV Ms. Kathleen Henner, State of CA, Brea, CA

Building 2 03/14/2001 Approodmately 1030 feet in length

= Denotes Sewer drainline pipe removed and replaced with new piping Section A Secti Section C 0

C>

Bld2

+

GENERAL ATOMIC5 FINAL RADIOLOGICAL SURVEY REPORT FOR THE BUILDING 2 SERVICE CORRIDOR DRAIN LINE TRENCH Prepared by: Laura Gonzales, Paul R. Maschka and Cornelius Stanley March 2001

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench

+vEN,,LATMMC Table of Contents L ist of T ables ii L ist of F igures...............................................................

ii Introduction..................................................................

1 Site D escription...............................................................

1 Criteria for Release to Unrestricted Use............................................

2 Exposure Rate Guideline 2

Soil R elease C riteria.....................................................

2 Instrum entation...............................................................

2 Previous Activities (History of Use)...............................................

3 Final Survey Plan.............................................................

3 Objectives and Responsibilities 3

Classification of A rea....................................................

3 Final Survey R esults...........................................................

4 Soil Sam ples...........................................................

4 Trench Exposure Rate Survey..............................................

5 Background Pit Exposure Rate Measurements and Background Soil Sample Results..........

5 B ackground............................................................

5 L ocation of Pit..........................................................

5 Surveys Performed and Results 6

C onclusion...................................................................

6 List of Tables Table 1:

Gamma Spectroscopy Results of Soil Samples from the Trench in Building 2 Service Corridor - Post Drain Line Removal (PDRL).....................

7 Table 2:

Background Soil Sample Results....................................

14 List of Figures (unpaged)

Figure 1:

Main Site and Sorrento Valley Figure 2:

Building 2 Service Corridor Drain Line Trench Soil Sample Locations Figure 3:

Building 2 Section A, (A2 through Al5) - Trench Exposure Rate Survey Figure 4:

Building 2 Section A, (A16 through A28) - Trench Exposure Rate Survey Figure 5:

Building 2 Section B, (B29 through B37) - Trench Exposure Rate Survey Figure 6:

Building 2 Section B, (B38 through B49) - Trench Exposure Rate Survey ii

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench +VEMZWIU ATO.CS Introduction General Atomics (GA) is continuing its efforts to decontaminate, as appropriate, and obtain the release to unrestricted use of selected facilities and land areas on its site. GA has completed the Final Radiological Survey of a trench inside the service corridor of Building 2. The trench was created during removal of the underground drain lines associated with the sewerage system within Building 2 (See Figure 1). Some of the drain lines were known to be radioactively contaminated. Because of this, and the fact that the lines were old and deteriorating, it was decided to remove all of them and dispose of them as radioactive waste. The drain lines were removed and replaced (with new plastic pipe) in sections at a time. The resulting sewer line trench runs though the entire service corridor (see Figure 2A), for a total length of approximately 1,030 feet.

After approval to backfill the trench has been received from the NRC, GA will backfill the trench with clean soil and pour a new concrete floor. A request to release the rest of the service corridor in Building 2 will be submitted sometime in the future. At the current time, it is important, for safety and other reasons, to backfill the trench caused by the drain line removal project.

This report documents the results of radiological measurements and gamma spectroscopy analyses of 104 soil samples collected from inside the trench after removal of the drain lines. The results of the surveys and analyses performed demonstrate that the trench meets the NRC-and State-approved criteria for release to unrestricted use. A summary of the results is provided in this report.

Site Description A plan view of the site is provided in Figure 1. Figure 2A shows the location of the trench in the service corridor.

The concrete floor in the service corridor was surveyed and contaminated areas were cleaned to levels below the approved release criteria. The floor was then cut into slabs and the concrete and top soil removed in order to expose the underground drain lines. The concrete and soil removed were placed in GA's Temporary Soil Staging Area, Bins T-48 and T-3 1, respectively. These bins have been surveyed and released by the NRC to unrestricted use by letter dated November 16, 2000 signed by Ms. Mary Adams. The underground drain lines which were mainly cast iron pipes, were removed and disposed of as radioactive waste and new plastic pipe installed. Post drain line removal (PDRL) soil samples were collected from the bottom of the trench in order to determine whether the soil was contaminated. Soil samples were processed (rocks and other debris removed, soil samples dried and weighed) and counted by gamma spectroscopy for at least 30 minutes.

I

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench

+CE*NE*RUAL*,CS Criteria for Release to Unrestricted Use Exposure Rate Guideline The guideline value for exposure rates measured at 1 m above the surface, is 10 IR/hr above background levels.

Soil Release Criteria The predominant radionuclides found in soil at GA and the soil release criteria (above background concentrations) in pCi/g for each of these radionuclides is provided below:

Cs-137 15 pCi/g Co-60 8 pCi/g Thorium (Th-228 + Th-232) 10 pCi/g Enriched Uranium (U-234 + U-235) 30 pCi/g Depleted Uranium 35 pCi/g If more than one radionuclide exists, the sum of the fractions of the concentrations is calculated as follows:

SC E

<1 j=1 L

Where Ci

=

The average concentration of radionuclides i in the soil above background levels.

Li =

The release criteria for radionuclides i.

The sum of the fractions must be less than one in order for the soil to meet the release criteria.

The U-235 concentrations determined by gamma spectroscopy will be used to ensure that concentrations of enriched uranium are below the given limit. The ratio of U-234 to U-235 is conservatively assumed to be' 30:1. The depleted uranium is estimated based on the amount of U-238 present since most of depleted uranium is U-238.

Instrumentation The only instrument used for exposure rate measurements was a calibrated microR meter (serial number 123930) manufactured by Ludlum Measurements which has a RCA 6199 coupled to a 1" x 1" Nal (TI) Scintillator. It has five ranges which go from 0-5 mR/hr and a typical background reading (measured at 1 m above the surface) of 10-18 /R/hr, unless building materials, geometry or other factors are involved. Exposure rate meters are calibrated quarterly.

2

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench +G,,m,.

A-,mm Previous Activities (History of Use)

Building 2 used to house GA's Science Laboratories which were involved mainly in research and development. Under normal operations, liquid radioactive waste was not permitted to be disposed of into the sanitary sewerage system. However, trace quantities could enter the sewerage system by the washing of glassware or other materials and supplies. As a result of this and because the sewer drain lines were old, the sewerage system was assumed to be contaminated (and measurements confirmed that a few portions of the system were contaminated). Consequently, the drain lines were removed and disposed of as radioactive waste.

Final Survey Plan Objectives and Responsibilities The objectives of the final survey plan were (1) that the exposure rates are less than 10 IR/hr above background measured at 1 meter above the surface, and (2) that the soil concentrations were below the approved soil release criteria.

Surveys were taken only by qualified Health Physics Technicians having a minimum of three years Health Physics experience in accordance with approved Survey Plans. Samples were counted in GA's Health Physics Laboratory which maintains an effective QA program.

The Survey Plan included (1) exposure rate surveying and (2) analyses of soil samples prior to and after the removal of the drain lines. The "prior to" samples represent soil that was stored in the SSA and has since been released by the NRC to unrestricted use. The results of soil samples collected after removal of the drain lines are provided in this report. In addition, the Survey Plan required that 100%

of the bottom surface of the trench and 10% of the sides of the trench be scanned using a microR exposure rate meter.

Classification of Area There was potential for the drain lines to have leaked and the soil to become contaminated. For this reason, the trench was surveyed as a suspect affected area which required samples to be taken - every 5 m (-15 feet) and the bottom of the trench scanned so that 100% coverage was obtained. The potential for the side of the trench to be contaminated was much less, therefore, only 10% of the sides needed to be scanned.

3

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench

+GFHMRAL ATP*cs Final Survey Results Soil Samples Table 1 provides the gamma spectroscopy results of the 104 post drain line removal soil samples.

All of the results are well below the applicable release criteria. The approximate locations where these soil samples were collected are shown in Figure 2B. The results are not discemable from background soil concentrations (see background pit soil sample results below).

Activation Product Concentrations - Evaluation The maximum Cs-137 detected in any of the soil samples measured 0.41 +/- 0.06 pCi/g (sample ID B2 C55-3). Co-60 was not detected in any of the soil samples (concentrations were < 0.1 pCi/g based on a 30 minute count and the 500 ml marinelli beaker sample geometry). See Table 1.

Therefore, the sum of the fractions assuming these concentrations were present, but not measured, is as follows: 0.1 pCi/g Co-60/8 pCi/g (limit) + 0.41 pCi/gm Cs-137 (maximum concentration found)/15 pCi/g (limit) = 0.02 or = 2% of the limits.

Thorium Concentrations - Evaluation All thorium results were at or near normal background levels and well below the 10 pCi/g limit. A comparison of the thorium soil concentrations for the trench soil samples with the thorium soil concentrations of the background pit samples indicates that the trench thorium concentrations are at or near background levels.

Enriched Uranium Evaluation All soil sample results were not discernable from background radiation levels for a 30 minute count; the maximum U-235 concentration in a soil sample was 0.38 pCi/g (soil sample ID B2 C54) and the maximum U-235 concentration in a background soil sample was 0.34 pCi/g, see Tables 1 and 2, respectively.

An evaluation of the soil samples results was performed (beyond reporting that the results are below the release criteria). The highest U-235 concentration was 0.38 pCi/g. For a 30 minute count, this value is not discernable from background. However, without subtracting background (assuming that this concentration is all due to contamination rather than background radiation), the maximum enriched uranium possible is as follows:

The enriched uranium limit (30 pCi/g) applies to the sum of the U-234+U-235 concentrations after background concentrations are subtracted. For enriched uranium, the ratio of U-234:U-235 can be as high as 30:1. Assuming a ratio of 30:1 (conservative), the maximum enriched uranium present when 0.38 pCi/g of U-235 is measured (without background subtraction) is 11.78 pCi/g (0.38 pCi/g of U 235 plus 11.4 pCi/g U-234); 11.78/30 =0.39 or -39% of the limits. If background is subtracted, then the value becomes much less than 39% of the limits.

4

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench +GE.AL *.OMCS Depleted Uranium Evaluation The maximum U-238 concentration (which is either natural uranium or depleted uranium), was 3.67 pCi/g (see Table 1). The maximum U-238 concentration in a background soil sample was 3.32 pCi/g.

See Tables I and 2, respectively.

An evaluation of the soil samples results was performed (beyond reporting that the results are below the release criteria). The highest U-238 concentration was 3.67 pCi/g. For a 30 minute count, this value is not discernable from background. However, without subtracting background (assuming that this concentration is all due to contamination rather than background radiation), the maximum depleted uranium possible is 3.67 pCi/g; the limit for depleted uranium is 35 pCi/g. Therefore, this result, without background subtraction, is = 10% of the allowable limits.

Trench Exposure Rate Survey Exposure rate surveys were performed on the soil surfaces of the trench. Scans covering essentially 100% of the soil surfaces along the bottom of the trench were performed. Scans covering about 10% of the soil surfaces of the walls of the trench were also conducted. The results of these scans are provided in Figures 3 through 8. The highest surface reading was 30 MuR/hr on the sides of the trench along I-beam B45. The exposure rate surface readings ranged from 20-30 MR/hr. These readings are consistent with background readings taken inside the "background pit" described below.

Background Pit Exposure Rate Measurements and Background Soil Sample Results

Background

A 4' x 4' x 4' hole, called the "background pit" was previously dug in a non-impacted area on GA's site called the Torrey Pines West Land Area on February 17-18, 2000. The underlying clay substrate was exposed in the pit. The background pit was used to gather background data in a similar environment as the data collected inside the trench of the Building 2 service corridor.

Radiation levels inside a hole or trench are naturally higher than they are on the soil surface due to the geometry of a trench. GA could then show that the radiation readings and uranium and thorium soil concentrations were due to naturally occurring radioactivity and not due to GA activities involving the use of radioactive materials.

Location of Pit The approximate location of the background pit in the Torrey Pines West Land Area is shown in Figure 9.

5

Final Radiological Survey Report for the Building 2 Service Corridor Drain Line Trench +-E",,,.,.s Surveys Performed and Results Measurements were taken in the "background pit" with two types of radiation survey instruments.

The instruments used and the results of the measurements are as follows:

1)

For the Ludlum Model 19 with a 1" X 1" Nal(T1) detector, exposure measurements ranged from 13 - 14 pR/hr outside the pit and 21 - 25 pR/hr inside the pit as shown in Figure 10.

2)

For the Ludlum Model 3 with the 2" X 2" NaI(TI) detector, exposure rate measurements ranged from 13 - 15 [tR/hr outside the pit and 25 - 27 jiR/hr inside the pit (contact) as shown in Figure 11. An exposure rate measurement taken 1 m from the pit soil surface (taken at the center of the pit) read 20 /.R/hr (as shown in Figure 11).

A study was also conducted using three different types of pipe; pvc, steel and aluminum. The pipes were each 6" in diameter and were buried in a vertical position with the deep end being 6' below the surface of the ground. This was done in the Torrey Pines West area. Radiation dose rate measurements were taken inside the pipes and the readings were as high as 31 /tR/hr inside the pipes. This is significantly higher than the normal background of 15 /.R/hr measured I m above the soil surface. The dose rate varied depending upon the type of pipe being used with the steel pipe providing more shielding than PVC or aluminum. See Figure 10.

A total of 21 soil samples were collected from the inside of the background pit and analyzed by gamma spectroscopy to determine natural uranium and thorium concentrations in clay soil. The locations are shown in Figure 12 and the results are provided in Table 2.

Conclusion The exposure rate surveys and the results of soil samples collected from the bottom of the drain line trench in GA's Building 2 service corridor demonstrate that the radiation levels inside the trench (formed after removal of the underground sewer drain line pipes) are well below the NRC-and State-approved release criteria for unrestricted use.

After approval to backfill the drain line trench in GA's Building 2 service corridor has been received from the NRC, GA will backfill the trench with clean soil and pour a new concrete floor. The rest of the Building 2 service corridor will be requested to be released sometime in the future.

6

TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCi/g) -

Resuits +/ Background not Subtracted - 30 minute counts Sample ID Beam Column Sam.ple 13 "Cs 60Co 2 *Th 228 Ra Total 23,U 235U Evaluaon and Location 662 keV Average of Average of (232Th)

Thorium 92.77 keV 186 (144)

Comments peak 1173/1332 238/583keV Average of 228Th+

peak keV peak keV peaks peaks 338/911 232Th keV peaks i _

B2 A2 A2 PDLR ND ND 1.31 +/- 0.12 2.06 +/- 0.42 3.36 2.70 + 0.93 0.23 +/- 0.26 Below Release Criteria B2 A3 A3PDLR ND ND 1.37+-0.14 2.06 +/- 0.40 3.43 3.67 +/- 0.99 0.19 +/- 0.07 Below Release Criteria B2 A4 A4 PDLR ND ND 1.21 +/- 0.12 1.88 +/- 0.35 3.09 2.09 +/- 0.59 0.23 +/- 0.06 Below Release Criteria B2 A5 A5PDLR 0.14 +/- 0.06 ND 1.14 +/- 0.30 2.02 +/- 0.44 3.16 2.51 +/- 0.81 0.24 +/- 0.06 Below Release Criteria B2 A6 A6PDLR ND ND 1.15 +/- 0.11 1.61 +/- 0.42 2.76 2.78 +/- 0.73 0.16 +/- 0.08 Below Release Criteria B2 A7 A7 PDLR 0.26 +/- 0.07 ND 1.18 +/- 0.12 1.82 +/- 0.64 3.00 2.26 +/- 0.09 0.29 +/- 0.07 Below Release Criteria B2S A8 A8 PDLR ND ND 1.24 +/- 0.12 1.71 +/- 0.29 2.94 2.64 +/- 0.63 0.17 +/- 0.08 Below Release Criteria B2 A9 A9 PDLR ND ND 1.25 +/- 0.16 2.42 +/- 0.54 3.67 2.10 +/- 0.73 0.21 +/- 0.10 Below Release Criteria B2S A1O A1O PDLR ND ND 1.27 +/- 0.12 1.79 +/- 0.38 3.07 3.24 +/- 0.70 0.16 +/- 0.08 Below Release Criteria B2A11 All PDLR ND ND 1.15 +/- 0.13 1.81 +/- 0.33 2.96 3.07 +/- 0.80 0.20 +/- 0.06 Below Release Criteria B2 A12 A12 PDLR ND ND 1.17 +/- 0.13 1.83 +/- 0.53 3.00 2.60 +/- 0.86 0.22 +/- 0.10 Below Release Criteria B2 A12-A A12 PDLR ND ND 1.15 +/- 0.11 2.17 +/-0.33 3.32 2.48 +/- 0.53 0.19 +/- 0.07 Below Release Criteria B2 A13 A13 PDLR ND ND 1.23 +/- 0.14 2.07 +/- 0.48 3.30 3.16 +/- 0.92 0.23 +/- 0.09 Below Release Criteria B2 A13-A A13 PDLR ND ND 1.09 +/- 0.12 1.64 +/- 0.51 2.73 1.97 +/- 0.86 0.14 +/- 0.08 Below Release Criteria B2SC A13-B A13 PDLR ND ND 1.18 +/- 0.10 1.86 +/- 0.33 3.04 2.65 +/-- 0.42 0.23 +/- 0.06 Below Release Criteria 7

TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCi/g) -

Results +/- 2o - Background not Subtracted - 30 minute counts Sample ID Beam Column :_..___...

S Saimple

"¢s 60Co 2 8Th I

28ýRa Total 238U t

35U Evaluation and Location 662 keV Average of Average of (232Th)

Thorium.

92.77 keV 186 (144)

Comments peak 1173/1332 238/583 keV Average of 228Th+

peak keV peak keV peaks peaks 338/911 2 IlTh keV peaks B2 SC A14 A14 PDLR ND ND 1.12 +/- 0.14 1.90 +/- 0.51 3.02 2.14 +/- 0.74 0.13 +/- 0.09 Below Release Criteria B2A15 A15 PDLR ND ND 1.17+/-0.13 1.94+/-0.41 3.11 3.05+/-0.92 0.24+/--0.11 Below Release Criteria B2 A16 A15 PDLR ND ND 1.58 +/- 0.18 2.96 +/- 0.65 4.54 1.34 +/- 1.21 0.18 +/- 0.13 Below Release Criteria B2A17 A17 PDLR ND ND 1.31 +/- 0.12 1.99 +/- 0.43 330 2.91 +/- 0.76 0.22 +/- 0.08 Below Release Criteria B2A18 A18 PDLR ND ND 1.09 +/- 0.11 1.74 +/- 0.36 2.83 2.72 +/- 0.72 0.24 +/- 0.07 Below Release Criteria B2-019 A19-PDLR ND ND 1.19 +/- 0.12 1.91 +/- 0.34 3.10 3.02 +/- 0.65 0.30 +/- 0.07 Below Release Criteria B2-020 A20-PDLR ND ND 1.28 +/- 0.12 2.01 +/- 0.39 3.29 3.44 +/- 0.78 0.26 +/- 0.08 Below Release Criteria B2 A20 A20 PDLR ND ND 1.00 :L 0.11 1.84 +/- 0.34 2.85 1.95 +/- 0.55 0.22 +/- 0.07 Below Release Criteria B2 A20-A A20 PDLR ND ND 1.01 +/- 0.07 1.31 +/- 0.16 2.42 1.66 +/- 0.38 0.18 +/- 0.05 Below Release Criteria B2 A21 A21 PDLR ND ND 1.18 +/-- 0.12 2.01 +/- 0.39 3.19 2.78 +/- 0.74 0.21 +/- 0.08 Below Release Criteria B2 A21-A A21 PDLR ND ND 0.98 +/- 0.05 1.71 +/- 0.18 2.68 2.22 +/- 0.33 0.21 +/- 0.04 Below Release Criteria B2 A22 A22 PDLR ND ND 1.24 +/- 0.12 2.09 +/- 0.34 3.33 3.03 +/- 0.67 0.21 +/- 0.09 Below Release Criteria B2 A22-A A22 PDLR ND ND 1.21 +/- 0.12 1.81 +/- 0.39 3.02 3.16 +/- 0.87 0.23 - 0.08 Below Release Criteria B2-23 A23-PDLR ND ND 0.70 +/- 0.07 1.11 +/-.021 1.81 1.56 +/- 0.37 0.16 +/- 0.06 Below Release Criteria B2 A23 A23 PDLR ND ND 0.94 +/- 0.11 1.39 +/- 0.30 2.33 1.96 +/- 0.64 0.14 +/- 0.11 Below Release Criteria 8

TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCi/g) -

Results +/- 2o - Background not Subtracted - 30 minute cOAnts Sample ID Beanm Column

___7_2__,

Sample I

37Cs 6()Co 0

28Th 228Ra Total 23SU 35U Evaluation and Location 662 keV Average of Average of (232Th)

Thorium 92.77 keV 186 (144)

Comments peak I1173/1332 238/583 keV Average of 22 8Th+

peak keV peak keV peaks peaks 338/911 1232Th keV peaks B2-24 A24-PDLR ND ND 0.83 +/- 0.08 1.28 +/- 0.24 2.11 1.48 +/- 0.46 0.16 +/- 0.05 Below Release Criteria B2-25 A25 PDLR ND ND 0.78 +/- 0.09 1.30 +/- 0.22 2.08 1.90 +/- 0.56 0.13 +/- 0.05 Below Release Criteria B2 A25 A25 PDLR ND ND 0.76 +/- 0.11 1.32 +/- 0.36 2.07 1.26 +/- 0.65 0.16 +/- 0.10 Below Release Criteria B2 A25-A A25 PDLR ND ND 0.50 +/- 0.08 0.95 +/- 0.29 1.45 1.62 +/- 0.64 0.07 +/- 0.06 Below Release Criteria B2-26 A26PDLR ND ND 0.84 +/- 0.09 1.32 +/- 0.27 2.16 1.85 +/- 0.43 0.15 +/- 0.06 Below Release Criteria B2 A26 A26PDLR ND ND 0.98 0.12 1.80 +/- 0.38 2.77 2.16 0.71 0.22 +/- 0.09 Below Release Criteria B2-27 27 PDLR ND ND 0.81 - 0.07 1.27 +/- 0.22 2.09 1.35 - 0.40 0.17 +/- 0.05 Below Release Criteria B2-28 28 PDLR ND ND 1.02 1 0.12 1.53 +/- 0.37 2.55 1.66 +/- 0.72 0.17 +/- 0.08 Below Release Criteria B2 B29 B29 PDLR ND ND 1.20 +/- 0.14 1.98 +/- 0.44 3.18 1.59 1.43 0.18 +/- 0.07 Below Release Criteria B2 B30 B30PDLR ND ND 0.94 +/- 0.12 1.84 +/- 0.45 2.79 1.89 1.41 ND Below Release Criteria B2 B31 B31 PDLR ND ND 0.85 0.13 1.69 +/- 0.43 2.54 1.66 +/- 0.76 0.14 0.09 Below Release Criteria B2 B32 B32 PDLR ND ND 0.97 +/- 0.11 1.67 +/- 0.36 2.64 2.31 +/- 0.65 0.26 +/- 0.27 Below Release Criteria B2 B32 -A B32 PDLR ND ND 0.31 +/- 0.08 0.64 +/- 0.24 0.95 1.11 +/- 0.55 0.13 +/- 0.06 Below Release Criteria B2 B32-B B32 PDLR ND ND 0.49 +/- 0.17 0.59 +/- 0.14 1.09 0.53 +/- 0.49 0.05 +/- 0.06 Below Release Criteria B2 B33 B33 PDLR ND ND 0.76 0.12 1.30 +/- 0.45 2.06 1.40 +/- 0.74 0.08:+/- 0.07 Below Release Criteria 9

TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCilg) -

Results +/--' 2o - Background not Subtracted - 30 minute counts Sam ple ID Beam Column Sample 137CS 60Co 228Th 228 Ra Total 238U 235U Evaluation and Location 662 keV Average of Average of (232Th)

Thorium [ 92.77 keV 186(144)

Comments peak 1173/1332 238/583 keV Average of 22'Th+

peak keV peak keV peaks peaks 338/911 232 T

keV peaks B2 B33-A B33 PDLR ND ND 0.29 +/- 0.07 0.46 +/- 0.23 0.75 1.09 +/- 0.46 0.06 +/- 0.05 Below Release Criteria B2 B34 B34 PDLR ND ND 0.58 +/- 0.09 0.77 +/- 0.29 1.35 0.84 +/- 0.48 0.10 +/- 0.06 Below Release Criteria B2 B34-A B34 PDLR ND ND 0.55 +/- 0.07 0.78 +/- 0.27 1.33 1.08 +/- 0.51 0.19 +/- 0.07 Below Release Criteria B2 B35 B35 PDLR ND ND 1.07 +/- 0.28 1.80 +/- 0.83 2.87 1.82 +/- 0.70 0.28 +/- 0.11 Below Release Criteria B2 B35-A B35 PDLR ND ND 0.36 +/- 0.10 0.57 +/-.0.25 0.93 0.67 +/- 0.44 0.10 +/- 0.05 Below Release Criteria B2 B36 B36 PDLR ND ND 0.49 +/- 0.09 0.86 +/- 0.39 1.35 0.89 +/- 0.71 0.07 +/- 0.06 Below Release Criteria B2 B37 B37 PDLR ND ND 0.97 +/- 0.12 1.72 +/- 0.41 2.69 2.20 +/- 0.82 0.13 +/- 0.05 Below Release Criteria B2 B38 B38 PDLR ND ND 0.59 +/- 0.10 1.32 +/- 0.45 1.91 ND 0.14 +/- 0.10 Below Release Criteria B2 B39 B39 PDLR ND ND 0.46 +/- 0.09 0.88 0.35 1.33 0.70 +/- 0.57 0.11 +/- 0.07 Below Release Criteria B2 B40 B40 PDLR ND ND 0.35 +/- 0.06 0.63 +/- 0.21 0.99 0.83 +/- 0.46 0.07 +/- 0.04 Below Release Criteria B2 B41 B41 PDLR ND ND 0.48 +/- 0.10 1.10 + 0.41 1.58 0.99 +/- 0.60 0.12 +/-- 0.07 Below Release Criteria BS SC B42 B42 PDLR ND ND 0.43 +/- 0.06 2.46 - 0.50 2.88 2.28 1 0.91 0.16 1 0.10 Below Release Criteria B2 SC B43 B43 PDLR ND ND 0.96 - 0.14 1.83 +/- 0.43 2.79 1.96 +/- 0.75 0.19 +/- 0.09 Below Release Criteria B2 B44 B44 PDLR ND ND 1.06 +/- 0.13 1.58 +/- 0.42 2.64 1.35 +/- 1.20 0.26 +/- 0.10 Below Release Criteria B2 B45 B45 PDLR ND ND 1.07 +/- 0.13 1.91 +/- 0.40 2.98 1.11 +/- 1.11 0.26 +/- 0.11 Below Release Criteria 10

TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCi/g) -

Results +/- 2o - Background not Subtracted - 30 minute counts Sample ID Beam Column i___...__"__

Sample 137CS 60Co 0 28Th 2N Ra Total 238u 2

I 35U Evaluation and Location 662 keV Average of Average of (232Th)

ThoriUm ' 92.77 keV 186(144)

Comments peak 11713/332 238/583 keV Average of "

8Th peak keV peak keV peaks peaks 338/911 232 Th keV peaks B2SC 46 B46PDLR ND ND 1.03 +/- 0.07 1.86 +/- 0.23 2.89 1.89 +/- 0.04 0.16 0.15 Below Release Criteria B2 B47 B47 PDLR ND ND 1.23 +/- 0.11 1.97 +/- 0.34 3.20 2.68 +/- 0.74 0.27 -0.07 Below Release Criteria B2SC 48 B48PDLR ND ND 1.21 +/- 0.15 2.40 +/-: 0.52 3.61 2.56 +/- 0.97 0.27 0.12 Below Release Criteria B2 B49 B49 PDLR ND ND 1.45 +/- 0.16 2.18 +/- 0.57 3.63 1.20 1.1 0.25 0.11 Below Release Criteria B2 B50 B50 PDLR ND ND 1.42 +/- 0.15 2.28 +/- 0.53 3.70 2.51 +/- 0.84 0.35 +/- 0.13 Below Release Criteria BS SOIL 26 C51 PDLR ND ND 0.84 +/- 0.09 1.32 +/- 0.27 2.16 1.85 + 0.43 0.15 - 0.06 Below Release Criteria B2 C52 C52 PDLR ND ND 1.41 +/- 0.16 2.32 +/- 0.45 3.74 1.09 1.19 0.28 0.10 Below Release Criteria B2 C53 C53 PDLR ND ND 1.41 +/- 0.14 2.52 +/- 0.60 3.93 1.77 0.75 0.25 + 0.13 Below Release Criteria B2 C54 C54PDLR ND ND 1.36 +/- 0.19 2.43 +/- 0.61 3.79 1.44 1.33 0.38 0.13 Below Release Criteria B2 S/C C-55 C-55 PDLR ND ND 1.09 +/- 0.11 1.25 +/- 0.43 1.94 1.09 +/- 0.60 0.12 +/- 0.07 Below Release Criteria B2 C55-3 C55-3 PDLR 0.41 +/- 0.06 ND 0.91 +/- 0.09 1.25 +/- 0.26 2.17 2.23 +/- 0.53 0.35 +/- 0.34 Below Release Criteria B2 C55-4 C55-4 PDLR ND ND 0.87 +/- 0.09 1.53 +/- 0.35 2.41 1.87 +/- 0.61 0.25 - 0.08 Below Release Criteria B2 S/C C-56 C-56 PDLR ND ND 0.79 0.10 1.20+/-0.31 1.99 2.44 0.81 0.17 0.08 Below Release Criteria B2 S/C C-57 C-57 PDLR ND ND 0.60 0.12 1.37 +/- 0.43 1.97 1.63 +/- 0.74 0.07 0.08 Below Release Criteria B2 S/C C-57 #I C-57#1 PDLR ND ND 0.63 +/-0.09 1.17 +/- 0.28 1.80 1.48 +/- 0.56 0.15 0.01 Below Release Criteria 11

TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCi/g) -

Results +/- 2y - Background not Subtracted - 30 minute counts Sample ID Beam Column Sample 137 Cs I

0Co 228Th l 228Ra Total 238U 23TU EEvaluation andi Location 662 keV Average of Average of 232Th)

Thorium 92.77 keV 186 (144)

Comments peak 1173/1332 238/583keV Averageof 221'Th+

peak keV peak keV peaks peaks 338/911 232Th keV peaks B2 S/C C57#2 C-57 #2 PDLR ND ND 0.75 +/- 0.12 1.42 +/- 0.46 2.18 1.41 +/- 0.71 0.10 +/- 0.07 Below Release Criteria B2 S/C C57#3 C-57 #3 PDLR ND ND 0.70 +/- 0.08 1.01 +/- 0.32 1.70 1.27 +/- 0.62 0.14 +/- 0.07 Below Release Criteria B2 S/C -57 #4 C-57 #4 PDLR ND ND 0.67 +/- 0.10 1.07 +/- 0.46 1.74 1.02 +/- 0.61 0.12 +/- 0.08 Below Release Criteria B2 SC C-58 C58 PDLR ND ND 0.46 +/- 0.07 0.61 +/- 0.25 1.07 1.40 +/- 0.68 0.10 +/- 0.05 Below Release Criteria B2 S/C C58#1 C58#1 PDLR ND ND 0.89 +/- 0.12 1.72 +/- 0.42 2.61 1.56 + 0.86 0.17 + 0.10 Below Release Criteria B2 S/C C58#2 C58 #2 PDLR ND ND 0.70 :L 0.11 1.25 +/- 0.35 1.95 1.66 +/- 0.62 0.13 - 0.07 Below Release Criteria B2 S/C C58#3 C58 #3 PDLR 0.14 +/- 0.06 ND 0.83 +/- 0.11 1.32 +/- 0.40 2.15 1.70 +/- 0.69 0.18 - 0.08 Below Release Criteria B2 S/C C58#4 C58 #4 PDLR 0.21 +/- 0.10 ND 0.80 +/- 0.13 1.48 +/- 0.44 2.29 0.92 +/- 0.94 0.23 - 0.10 Below Release Criteria B2 C59 C59 PDLR ND ND 0.59 +/- 0.08 0.91 +/- 0.25 1.49 0.78 + 0.77 0.12 - 0.06 Below Release Criteria B2 C60 C60 PDLR ND ND 0.65 +/- 0.10 1.43 +/- 0.43 2.08 1.61 +/- 0.75 0.10 -0.06 Below Release Criteria B2 C60A C60A PDLR ND ND 0.48 - 0.08 0.87 +/- 0.27 1.35 0.93 +/- 0.88 0.07 - 0.05 Below Release Criteria B2 C61 C61 PDLR ND ND 0.93 +/- 0.11 1.51 +/- 0.36 2.43 1.47 +/- 0.40 0.10 +/- 0.08 Below Release Criteria B2 C62 C62 PDLR ND ND 0.55 +/- 0.08 0.90 + 0.28 1.46 1.55 +/- 0.49 0.11 + 0.06 Below Release Criteria B2 C62-A C62 PDLR ND ND 0.74 +/- 0.14 1.53 + 0.48 2.27 1.32 +/- 0.76 0.13 - 0.09 Below Release Criteria B2 C63 C63 PDLR ND ND 0.48 +/- 0.07 0.85 + 0.27 1.32 1.18 + 0.52 0.07 + 0.05 Below Release Criteria 12

"TABLE 1: Gamma Spectroscopy Results of Soil Samples Collected Post Drain Line Removal in the Building 2 Service Corridor From The Period September 1999 through February 2001 Radionuclide Concentration (pCi/g) -

Results + 2o - Background not Subtracted - 30 minute counts Sample iD Beam Column i_'______

Sample 137 s 60Co 228Th 228 Ra Total 2 3 U 2 5U Evaluation and Location 662 keV%

Average of Average of (232Th)

Thorium 92.77 keV 186 (144)

Comments peak 1173/1332 238/583 keV Average of 22Th+

peak keV peak keV peaks peaks 338/911 23Th keV peaks

]

B2 C-63-A C63 PDLR ND ND 0.80 +/- 0.11 1.26 +/- 0.37 2.05 2.00 +/- 0.72 0.13 +/- 0.07 Below Release Criteria B2 C-63-B C63 PDLR ND ND 0.48 +/- 0.07 0.85 +/- 0.27 1.32 1.18 +/- 0.53 0.07 +/- 0.05 Below Release Criteria B2 C-64 C64 PDLR ND ND 0.55 + 0.06 0.92 +/- 0.11 1.47 1.48 +/- 0.52 0.08 +/- 0.05 Below Release Criteria B2 C-65 C65 PDLR ND ND 0.46 +/- 0.10 1.16 +/- 0.43 1.62 1.34 +/- 1.10 0.09 - 0.08 Below Release Criteria B2 C66 C66 PDLR ND ND 0.58 +/- 0.11 0.78 +/- 0.30 1.36 0.95 +/- 0.55 0.20 + 0.09 Below Release Criteria B2 C67 C67 PDLR ND ND 1.04 +/- 0.13 1.95+ 0.48 3.00 1.71 + 0.75

.019 0.10 Below Release Criteria B2 C68 C68 PDLR ND ND 0.56 +/- 0.07 0.99 + 0.33 1.55 1.62 + 0.53 0.11 + 0.06 Below Release Criteria B2 C69 C69 PDLR ND ND 0.57 + 0.10 0.96 +/- 0.27 1.54 1.64 +/- 0.80 0.09 +/- 0.06 Below Release Criteria B2 C70 C70 PDLR ND ND 0.80 +/- 0.10 1.20 + 0.30 2.00 1.69 + 0.61 0.12 +/- 0.06 Below Release Criteria B2 C71 C71 PDLR ND ND 0.60 + 0.10 1.08 + 0.30 1.68 1.67 + 0.59 0.10 +/- 0.06 Below Release Criteria B2 C72 C72 PDLR ND ND 0.65 + 0.12 1.06 +/- 0.45 1.71 0.88 + 0.74 0.08 + 0.06 Below Release Criteria B2 C-73 C73 PDLR ND ND 0.97 +/-.011 1.70 +/- 0.33 2.67 1.99 +/- 0.62 0.19 +/- 0.07 Below Release Criteria B2 C74 C74 PDLR ND ND 0.70 + 0.10 1.28 +/- 0.36 1.98 1.20 + 0.54 0.17 + 0.10 Below Release Criteria B2C75 C75 PDLR ND ND 0.63 +/- 0.10 1.14 + 0.38 1.78 1.35 + 0.54 0.13 +L 0.09 Below Release Criteria NOTES

3)

ND Means:

137Cs = <0.1 pCi/g 6°Co = <0.1 pCi/g 235U = <0.2 pCi/g 238U = <3-0 pCi/g 13

Table 2: "Background Pit" Soil Sample Results Radionuclide Concentrations (pCi/g)

Sample Number 235U 23SU 28Th 232Th BKG PIT # 1 0.24 + 0.11 2.45 +/- 0.74 1.44 + 0.16 2.23 + 0.54 BKG PIT # 2 0.23 +/- 0.07 2.80 +/- 0.66 1.56 + 0.14 2.10 +/- 0.43 BKG PIT # 3 0.27 + 0.11 2.73 + 0.82 1.42E -0.16 2.72 +/- 0.61 BKG PIT # 4 0.34 +- 0.11 2.62 +/- 0.69 1.23 +/-- 0.13 1.77+/-L 0.43 BKG PIT # 5 0.19 - 0.11 2.56 +/- 0.85 1.56 + 0.24 2.29 +/- 0.61 BKG PIT # 6 0.21 +/- 0.08 2.67 + 0.72 1.22 +/- 0.10 1.85 +/- 0.41 BKG PIT # 7 0.24 + 0.10 2.56 + 0.88 1.23 + 0.16 2.40 + 0.50 BKG PIT # 8 0.20 +/- 0.09 2.35 +/- 0.68 1.12+:L 0.11 1.73 +/- 0.37 BKG PIT # 9 0.11 + 0.09 2.02 +/- 0.86 1.15 +/- 0.14 1.93 +/- 0.47 BKG PIT# 10 0.20+ 0.07 2.99 + 0.74 1.18 + 0.13 1.78 + 0.39 BKG PIT # 11 0.20 +/- 0.11 1.77:+ 0.72 1.27 + 0.15 1.95 +/- 0.52 BKG PIT # 12 0.24 + 0.08 2.45 + 0.75 1.35 + 0.12 2.07+ 0.42 BKG PIT # 13 0.24 + 0.11 3.32 + 1.15 1.44 + 0.17 2.34+ 0.56 BKG PIT # 14 0.23 +0.07 3.39 + 0.80 1.36 +/- 0.15 2.29 + 0.42 BKG PIT # 15 0.23 + 0.12 2.60 +0.91 1.40 + 0.18 2.34 + 0.59 BKG PIT # 16 0.21 - 0.09 3.17 + 0.92 1.30 + 0.12 2.29 +/- 0.40 BKG PIT # 17 0.23 + 0.10 2.46 + 0.79 1.48 + 0.14 2.57 + 0.45 BKG PIT# 18 0.25 +/- 0.08 2.86+ 0.54 1.74 + 0.19 1.91 + 0.37 BKG PIT # 19 0.16 + 0.10 2.39 + 0.85 1.36 + 0.13 1.95 + 0.52 BKG PIT # 20 0.21 +/- 0.08 3.06 + 0.76 1.26 + 0.13 2.15 + 0.35 BKG PIT # 21 0.17 + 0.09 2.14 + 0.83 1.27 4+ 0.15 2.21 + 0.55 Average 0.21 + 0.09 2.64 + 0.80 1.36+:- 0.15 2.03 + 0.47 Range 0.12 to 0.30 1.84 to 3.44 1.21 to 1.51 1.56 to 2.50 14

Figure 1: Main Site and Sorrento Valley Site Names Building Numbers Building 1 Building 2 Building 7 Building 9 Building 10 Building 13 Building 14 Building 15 Building 19 Building 21 Building 22 Building 23 Building 25 Building 27 Building 27-7 Building 29 Building 29-2 Building 30 Building 31 Building 31-1 Building 31-2 Building 31-3 Building 33 Building 33-1 Building 33-5 Building 34 Building 34-1 Building 34-2 Building 34-3 Building 35 Building 35-1 Building 36 Building 37 Building 39 Building 39-1 Building 41 Building 42 Building 45 Building 63 Building 64 Building 65 Building 66 Building 66 r A Adminislration Science Laboratories A. B. C Cafeteria Experimental Building Maintenance Building Technical Office Building Technical Office East Technical Office Easl Swimming Pool Building TRIGA Building TRIGA Fuel Lab Building Hot Cell Waste Yard Building Experimental Area Experimental Area Experimental Area Emergency Vehicle Sturage Building LINAC Complex TRIGA Storage Building Neutron Radiography Building ECF Critical Building Storage Building Fusion Building Fusion Lab Building Fusion Building Annex 5 Fusion Doublet III Building Fusion Doublet IIl Capacitor Building Fusion Doublet ItI Lab Building Fusion Doublet Ill Storage Building Test Tower Building Facilities (Shipping & Receiving) Building Blower Assembly Building Sorrento Valley Building Sorrento Valley Building Storage Building Raw Stock Facility NDT Facility Helium Circulator Test Facility 3550 Dunhill St.

11030 Roselle St.

11040 Roselle St.

3529 Duhil, St.

3510 Cunhill St t/

ITE OPEN SPACE LOTS 27-1 Trailer g2 LOTS UCSD LOTS FENCING PROPERTY LINE 0

250 500 750 1000 SCALE IN FEET N

S SITE LU cc I--

Figure 2A: Building 2 Service Corridor Approdmately 1030 feet in length

= Denotes Sewer drainline pipe removed and replaced with new piping Section A Secte Section C 03/14/2001 Bid2 (1 a

Figure 2B: Building 2 Service Corridor Drain Line Trench Soil Sample Locations

-A-27 A-26 A-25 B-30 B-31 B-33 B-34 B-35

-A-20 A-1 9 "A-18

"-A-17 A

B-39 A-8 A-5 C-73 Section C 0-64 C-75 0-72 0-62 Bld2 02/11/2001 A-1 A-1 3

Figure 3: Building 2 Section A, Micro-R Survey, (A2 Through A15)

Trenchline Exposure Rate Survey Technicians J. Vassett J. Sullivan Date: 11117100

=100%

bottom of trench 77

=10% of sdewalls All readings are in 1iR/hr.

Instrument # - Model 19 Serial#

123930 Due 01/15/00 Size.& Type.

lxi NaI(TI) *y Ef%-

N/A

Background

20-24 (trench)

Bid2-A-2

Figure 4: Building 2, Section A, Micro-R Survey, (A16 Through A27)

Trenchline Exposure Rate Survey Technicians J. Vassett J. Sullivan Date: 11/17/00

= 100 % @ bottom of trench

= 10% of sidewalls Serial #

123930 Que,01/15100 Size & Type lx1 Nal(TI) y

-Background 20-4(iir--iiV BId2-A-1 Model 19 Instrument #

Figure 5: Building 2, Section B, Micro-R Survey (B28 Through B37)

Trenchline Exposure Rate Survey Technicians: L S. Cowan S. Finchum A

J. Sullivan Date: 10128/00

= 100 % @ bottom of trench

= 10% of sidewalls All readings are in gi R/hr.

seriai a 123930 Due

• 01115/00 Size,& Type lxI Nal(TI) y Effg N/A Background 120-24 (trench)

Bld2-B-2 t

Figure 6: Building 2, Section B, Micro-R Survey (B38 Through B49)

Trenchline Exposure Rate Survey Technicians:

S. Cowan S. Finchum4 J. Sullivan Date: 10128100

=100% @bottom oftrench

1. F

= 10% of sidewalls All readings are in gR/hr.

Bld2-B-1 nstrutnent #

Model 19

• i~*[ii~li,,123930 Se01115100 5Ize & Type lxI Nal(TI)y lie 2NIA Oacground 20-24 (trench

Figure 7: Building 2, Section C, Micro-R Survey (C50 Through C63)

Trenchline Exposure Rate Survey Technicians J. Vassett J. Sullivan Date: 11/16/0(

=100% @bottomoftrench

1. -#= 10% of sidewalls All readings are in [LR/hr.

insMument # Model 19 Sera.igi.. r#

123930 Due____

'Size & Type lx1 Nal(TI) y E7 N/A Backgrqupd: 20-24 (trench)

BId2-C-2

Figure 8: Building 2, Section C, Micro-R (C64 Through C76)

Trenchline Exposure Rate Survey Technicians J. Vassett J. Sullivan Date: 111161/

=100% @bottom of trench

= 10% of sidewalls All readings are in tR/hr.

Instrument.# Model 19 Serial #

123930 DUe 01/15/00 Size & Type lxi Nal(TI) y Eff %

N/A

Background

20-24 (trench)

BId2-C-1

Figure 9: Torrey Pines West Land Area (showing Background Pit Location)

Wood Storage Area Metal Torrey Pines West

Figure 10 BACKGROUND PIT 02/18/2000 - 02/25/2000 LUDLUM MODEL 3 with 2"x 2" NaT (TI) Detector A R/hr) 14 25 26 15 Top View 15 14 25 25

-26 27 27 27 26 27 25 26

-27 25 25 25 S...26 2727 4

27 27 27 26

ý.271 26 25 25 25 25 25 14 14 Steel Ground k.

14 PIPE BACKGROUNDS LUDLUM MODEL 3 with 2"x 2" NaT (TI) Detector ft R/hr)

Pipe Diameter 6 inches PVC 8

10 1'

19 2'

21 3'

24 4'f 24 5'

23, 6'

22 13 20 Micro-R per hour @ one meter from bottom center of pit 4 ft 4 ft All readings recorded in ý.R/hr (on surface of soil)

• 4ft deep pit dug in clay-type soil in Torrey Pines West land area.

12 13 1'-- 22 W

S 4

V, N

E Aluminum 13 13 1'.

24 116" SA 2'

28 2'

27 3'

29 3'

29 4'

31 4'

5'-

29 5'

30 61 30 6' -- 29 6' - 29 Background Pit Survey Model-3 N/A N/A N/A 1,17819 N/A N/A N/A 08/09/2000 N/A N/A N/A N/A N/A N/A N/A y

N/A NiA N/A 153765 N/A N/A N/A 44-10 N/A N/A N/A Comments: All readings recoi ded in Micio-R pei Ih

ý Siiai-*c:C' SsidIy R Hun/,r lW'k

)aite:02/L1/2000 - 02/25/22000 t

V 25 25 27 26 zo

Figure II 14 Top View 14 13 BACKGROUND PIT LUDLUM MODEL 19 Vt R/hr Meter 13 13 13 13 13 20 Micro-R per hour g one meter from bottom center of pit A.

• ":* 1.,

4 ft 4 ft All readings recorded in pR/hr (on surface of soil)

• 4ft deep pit dug in clay-type soil in Torrey Pines West land area.

w sy4 I

N E

02/25/2000 Backgrouitd Pit Survey hl~mlfftýs)

Model-19 N/A\\

N/ A/

Sma) Nmibpr 14,1068 N/A N/A N/A Cullib-,qiw Due 04/06/2000 N/A N/A N/A SN/A N/A N/A N/A Y

y N/A N/A N/A Pi::e Size N/A N/A N/A N/A C(onmlenls:

Al] reading wcorded in Micro-R per hr Sigat ure: Ci vriCtýqw'C Date: 02L28206

BACKGROUND PIT SOIL SAMPLE LOCATIONS 2

45 16F 17 18 6

21 7

14' 20 19 8

12 10"!

n

= Denotes Soil Sample Location W

S

-A

'- N E

02/18/2000 B. Huntei C. Stanley 0 All soil samples begin with BP-s-n Figure 12 Top View A

4ft v

"-4 4ft