Text

General Atomics, Request to Release Certain Portions of General Atomics Facility to Unrestricted Use and Delete Them from Its License: Namely, Sewer Trench S-18 to S-15 to S-13
	ML020430517
Person / Time
Site:	07000734
Issue date:	02/04/2002
From:	Asmussen K; General Atomics
To:	Adams M; NRC/NMSS/FCSS
References
	-RFPFR, 696/CAL-3429
	Download: ML020430517 (90)
	v • d • e

4 GENERAL ATOMICS February 4, 2002 696/CAL-3429 VIA EXPRESS DELIVERY SERVICE Ms. Mary Adams 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 its License: Namely, Sewer Line Trench S-18 to S-15 to S-13 and Ms. Sudana Kwok (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 its License: Namely, Sewer Line Trench, S-18 to S-15 to S-13

Dear Ms. Adams and Ms. Kwok:

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.

In July 2001, GA initiated an extensive project to survey, and remediate if necessary, the GA site sewer system that had the potential of being impacted by activities involving the use of radioactive material. A "Sewer Survey Plan" was prepared to describe the scope of this project. At that time, twenty (20) sewer vaults on GA's Main Site and two (2) sewer vaults on GA's Sorrento Valley Site were identified.

During implementation of the Sewer Survey Plan, sewer vault S-15 located near Building 25 on GA's Main Site was found to be radiologically contaminated (See attached Figure 1 for relative location of S-15 on GA's Main Site). The predominant radionuclide was Cs-1 37 with smaller concentrations of Co-60.

3550 GENERAL ATOMICS COURT, SAN DIEGO, CA 92121-1122 P0 BOX 85608, SAN DIEGO, CA 92186-5608 (858) 455-3000

696/CAL-3429 February 4, 2002 Page 2 Subsequently, contamination was found in associated drain lines between vault S 15 and Building 25 and between S-15 and vault S-1 3 (See attached Figure 2). It was also believed that there was potential for contamination in the drain line between S-15 and S

18. Accordingly, the sewer drain lines between S-15 and Building 25, between S-15 and S-18, and between S-15 and S-13 were all excavated and disposed of as low level radioactive waste. Similarly, the S-15 vault itself was excavated and disposed of as low level radioactive waste. In addition, a contaminated vault which was uncovered between S-15 and S-13 while excavating the sewer drain line (see below) was also excavated and disposed of as low level radioactive waste.

About 300 feet downstream from the S-15 sewer vault (i.e., in the direction of S-13),

a large eucalyptus tree was found to be inhibiting the removal of the drain line. The tree was cut down and the nearby asphalt removed in order to remove the drain line. During this process, a sewer manhole which had previously been covered over with asphalt was unearthed. This vault had been invaded by the root system of the eucalyptus tree which had been cut down. Consequently, this vault and tree were both also disposed of as low level radioactive waste.

The soil removed from the trench during the above described sewer line and vault excavation is piled alongside the trench.

Initially, GA had planned to document the entire "Sewer Project" in one report.

However, after removal of the above described vaults and associated drain lines, a sewer line trench -772 feet long and -4 feet wide now exists. The trench between S-18 and S 13 (see Figure 2) varies in depth from -3 feet to -12 feet depending on the terrain. This trench needs to be backfilled as soon as possible for safety and other reasons. Therefore, GA is hereby requesting the release of this trench and the soil therefrom prior to requesting the release of the remainder of the "Sewer Project."

Enclosed is GA's report titled "General Atomics' Final Radiological Survey Report for the Sewer Line Trench, S-18 to S-13" dated February 2002. This Final Radiological Survey Report documents the results of GA's radiological measurements and soil sampling and analysis of the 772 foot (235 meter) trench and the soil removed from the trench. The results of these surveys and analyses demonstrate that this trench and the removed soil meets the NRC-and State-approved criteria for release to unrestricted use and that backfilling the trench is warranted.

GA hereby requests both the Nuclear Regulatory Commission (NRC) and the State of California Department of Health Services' Radiologic Health Branch (State) to release this excavation trench and the soil removed therefrom, as described in the enclosed report, to unrestricted use so that GA may use the removed soil for (1) backfilling the trench, (2) for backfilling pits or trenches in other areas on GA's site, or (3) disposing of it in a local landfill.

696/CAL-3429 February 4, 2002 Page 3 It is GA's understanding that the NRC will conduct confirmatory surveys; the results of which will be made available to the State.

A Final Radiological Survey Report for the rest of the Sewer Project will be submitted in the near future with a request to release the remainder of the sewer vaults and sewer drain lines on GA's site to unrestricted use.

If you should have any questions regarding this request or the enclosed report, please contact Laura Q. Gonzales at (858) 455-2758, or me at (858) 455-2823. Your assistance in responding to this request is very much appreciated.

Very truly yours, 6i*ýf 6. Ow-ý Keith E. Asmussen, Ph.D., Director Licensing, Safety and Nuclear Compliance

Enclosure:

GA report titled: "General Atomics' Final Radiological Survey Report for the Sewer Line Trench, S-18 to S-13" dated February 2002 cc:

Dr. D. Blair Spitzberg, Chief, NMSS Branch 3, Region IV Mr. Wayne L. Britz, Fuel Cycle Inspector, NRC Region IV Mr. Robert Evans, Fuel Cycle Inspector, NRC Region IV Ms. Kathleen Henner, State of CA, Brea, CA Ms. Mina Goeders, State of CA, Sacramento

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GENERAL ATOMICS' FINAL RADIOLOGICAL SURVEY REPORT FOR THE SEWER LINE TRENCH, S-18 TO S-15 TO S-13 Prepared By: William LaBonte, Laura Gonzales, Barbara Lyons, and Cornelius Stanley Illustrated By: Cornelius Stanley Final Survey Technicians: Cornelius Stanley, Barbara Lyons, Joseph Sullivan, and Scott Cowan February 2002

Table of Contents INTRODUCTION......................................

SITE DESCRIPTION...................................

HISTORY OF USE.....................................

DECONTAMINATION AND SURVEY ACTIVITIES.........

Soil Removed from the Trench......................

S-18 to S-15 Trench S-15 to S-13 Trench CLASSIFICATION.....................................

CRITERIA FOR RELEASE TO UNRESTRICTED USE.......

Release Criteria for Soils................................

Exposure Rate Guideline INSTRUMENTATION AND BACKGROUND MEASUREMENTS....

Background Soil Concentrations of Concern.................

Exposure Rate Background SITE DECOMMISSIONING PLAN REQUIREMENTS COMPARED TO Exposure Rate Scanning and Fixed Measurements......

Soil Sam pling...................................

FINAL SURVEYS PERFORMED AND RESULTS...........

Objectives and Responsibilities Survey Plan.....................................

Preparation and Counting of Soil Samples.............

Exposure Rate Scans..............................

Investigation of 37 [R/hr Area of Trench........

Hot Particle Found Exposure Rate Fixed Measurements..................

Final Samples Collected and Analyzed CO N CLU SION........................................

SURVEYS PERFORMED I....................

.....I...............

List of Tables Table 1:

Table 2:

Table 3:

Table 4:

Table 5:

Table 6:

Table 7:

Table 8:

Table 9:

Table 10:

USNRC's Acceptable Surface Contamination Levels..........................

State of California's Acceptable Surface Contamination Levels..................

S-18 to S-13 Sewer Drain Line Removal List of Instruments....................

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

Background M easurement in Pits..........................................

Surface Soil Sample Results, S-18 to S-13 Sewer Line Removal.................

Initial Samples, S-15 to S-13 Sewer Drain Line and Vault Sludge Sample Results PDLR Soil Samples Results, S-18 to S-13 Sewer Line Removal Pipe Trench.....

S-18 to S-13 Sewer Drain Line Trench Final Soil Sample Results................

Final Soil Sample Results from the S-18 to S-15 Trench.......................

ii

....... 7 7

7 8

8 8

9 9

10 11 11 14 T-1 T-2 T-3 T-4 T-5 T-6 T-12 T-17 T-21 T-46 2

- - 2

- - 3

- - 3

- - 3 4

- - 6

...6

6.

List of Figures (unpaged)

Figure 1:

Main Site and Sorrento Valley Site Figure 2:

Torrey Pines (Main) Site Sewer Lines Figure 3A:

Photo/Drawing of S-18 to S-13 Drain Line Trench Figure 3B:

S-18 to S-13 Trench Measurements Figure 4:

Disassembly of the S-15 Sewer Vault Figure 5:

Location of the Contaminated Tree Figure 6:

The Root Figure 7:

Removal of the Uncovered Sewer Vault Discovered During Removal of the Sewer Line Figure 8:

The Tree Figure 9:

S-18 to S-15 Surface Soil Samples and Direct Radiation Measurements Figure 10:

S-18 to S-13 Surface Soil Samples and Pipe Sludge Sample Locations Figure 11:

S-18 to S-13 Post Drain Line Removal Soil Sample Locations Figure 12:

S-15 to S-13 Final Survey Soil Sample Locations Figure 13:

S-15 to S-13 Final Survey Fixed Radiation Measurement and Results Figure 14:

S-15 to S-13 Final Survey Direct Radiation Scan Survey Locations and Results Figure 15:

S-18 to S-15 and Building 25 to S-15 Final Soil Sample Locations Figure 16:

S-18 to S-15 and Building 25 to S-15 Final Survey Direct Radiation Scan Survey Locations and Results Figure 17:

S-18 to S-15 and Building 25 to S-15 Final Survey Fixed Radiation Measurements and Results Appendixes Appendix A: Final Survey Plan for S-15 Sewer Vault Pipe Trench ii

+GENERALATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 Introduction General Atomics (GA) is continuing its efforts directed at decontaminating, as appropriate, and obtaining the release to unrestricted use of selected facilities and land areas at its site. In July 2001, GA initiated an extensive project to survey, and remediate if necessary, the GA site sewer system that had the potential of being impacted by activities involving the use of radioactive material. At that time, twenty (20) sewer vaults on GA's Main Site and two (2) sewer vaults on GA's Sorrento Valley Site were identified.

During implementation of the Sewer Survey Plan, sewer vault S-15 on GA's Main Site was found to be radiologically contaminated. The predominant radionuclide was Cs-137 with smaller concentrations of Co-60. Decontamination of the vault in-place was not a desirable option due to the extent of contamination inside the vault. Therefore, GA removed the contaminated vault and the associated sewer drain lines. These associated drain lines are (1) the drain line between the S-18 and S-15 sewer vaults, (2) the drain line between the S-15 and S-13 sewer vaults and (3) the drain line between Building 25 and the S-15 sewer vault (referred to herein as "S-18 to S-15 to S 13 ", or more simply as "S-18 to S-13".

About 300 feet downstream from the S-15 sewer vault, a large eucalyptus tree was found to be inhibiting the removal of the drain line. The tree was cut down and the nearby asphalt removed in order to remove the drain line. During this process, a sewer manhole and vault which had previously been covered over with asphalt was unearthed. This vault had been invaded by the root system of the eucalyptus tree which had been cut down. The roots apparently acted as a dam/filter, and entrapped large quantities of sludge that had high levels of Cs-137, Co-60, uranium and thorium. Radiation readings on the root were about 140 itR/hr. The two contaminated vaults, i.e., S-15 and the uncovered vault, the sewer drain lines between them, and the tree were disposed of as radioactive waste. The drain line was removed up to the S-13 sewer vault (this vault was replaced because it had a crack in it). The soil removed from the trench during sewer line removal is piled alongside of the trench.

Initially, GA had planned to document the entire Main Site and Sorrento Valley site "Sewer Project" effort and results in one report. However, after removal of S-15 and the recently uncovered vault and associated drain lines, a sewer line trench -772 feet long and -4 feet wide now exists. The trench (which runs between the S-18 vault and the S-13 vault) varies in depth from -3 feet to -12 feet depending on the terrain. This trench needs to be backfilled as soon as possible for safety and other reasons.

This Final Radiological Survey Report documents the results of GA's radiological measurements and soil sampling and analysis of the 772 foot (235 meter) trench and the soil removed from the I

+ GENERAL ATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 trench. The results of these surveys and analyses demonstrate that this trench and the removed soil meets the NRC-and State-approved criteria for release to unrestricted use and that backfilling the trench is warranted.

GA is requesting both the Nuclear Regulatory Commission (NRC) and the State of California (DOHS/RHB) to release this excavation trench and the soil removed from this trench, to unrestricted use. GA plans to use the removed soil for (1) backfilling the trench, (2) for backfilling pits or trenches in other areas on GA's site, or (3) disposing of it in a local landfill; therefore release of this soil is also being requested.

A Final Radiological Survey Report for the remainder of the Sewer Project will be submitted in the near future with a request to release all of the other sewer vaults and sewer drain lines on GA's site to unrestricted use.

Site Description Figure 1 shows GA's Main Site and Sorrento Valley Site. In July 2001, at the beginning of the "Sewer Project", there were 20 sewer vaults identified on GA's main site as shown in Figure 2.

The S-18 to S-13 sewer line trench which is the subject of this report is shown in Figure 3A.

This figure is an aerial view showing the area where the trench is located on GA's main site.

Figure 3B provides dimensions. The entire sewer line trench is approximately 772 feet long, 4 feet wide, and varies from 3 feet to 12 feet deep depending on the terrain. The trench lies between the S-18 and S-13 sewer vaults as shown in Figures 2, 3A and 3B.

History of Use Beginning in the late 1980's, Building 25 (a small corrugated metal building on a concrete pad) was built as a low level radioactive liquid waste treatment facility. Liquid waste (e.g. mop water from GA's nuclear facilities), was brought to Building 25 for filtration and release into the sanitary sewerage system. Releases were only authorized when radioactive levels in the effluent were below the regulatory limits. The filtered liquids were released into the sewer drain system which flowed into the S-15 vault and eventually was pumped into the San Diego Municipal Sewerage System. The contamination (Cs-137, Co-60, uranium, and thorium) found in this portion of GA's sewerage system was most likely caused by these activities.

To a lesser extent, contamination of the sewer system could have come from nuclear activities which occurred inside Building 27 (the chemistry/radiochemistry building), (2) Building 23 (the Hot Cell Facility), and Building 22 (TRIGA Fuel Fabrication Facility). These facilities have since been decommissioned and released to unrestricted use. Contamination from these facilities 2

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GENERALATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 is considered less likely because radioactive liquids were collected in tanks or drums at their point of generation and did not directly go into the sanitary sewerage system from any of these facilities.

Decontamination and Survey Activities In July 2001, GA initiated an extensive project to survey, and remediate if necessary, the GA site sewer system that had the potential of being impacted by activities involving radioactive material. A Radiological Work Authorization was approved which incorporated detailed operating procedures, survey procedures for the sewer manholes; i.e, "sewer vaults", survey procedures for the sewer drain lines, training requirements, a list of authorized individuals, and other requirements and restrictions to safely conduct this survey. At the time, twenty (20) sewer vaults on GA's Main Site and two (2) sewer vaults on GA's Sorrento Valley Site were identified.

Contamination detected in vault S-15 and in the sewer line between S-15 and S-13 lead to the excavation of the entire sewer line between these two vaults. Because of the potential for contamination, the sewer line was also removed from between S-15 and S-18. This resulted in a trench extending from S-18 to S-15 to S-13.

Soil Removed from the Trench All soil removed from the trench during sewer drain line removal was piled up alongside of the trench. A total of 70 soil samples were collected and analyzed by gamma spectroscopy. GA is requesting that this soil be released to unrestricted use. GA plans to: (1) use this soil for backfilling the trench, (2) use it for fill at other areas on GA's site, or (3) dispose of it in a local landfill.

S-18 to S-15 Trench During the survey of the S-18 vault, levels of radioactivity as high as 5 mR/hr were found along the bottom of the sewer vault. The sludge in the bottom of the vault was removed and discarded as radioactive waste. Following the removal of the sludge, a piece of metal, that had contact radiation levels of 5 mR/hr (due to Cs-137 contamination) was discovered laying on the bottom of the vault. It was removed and packaged as radioactive waste. Removing the piece of metal and the sludge reduced the radiation levels from 5 mR/hr (5,000 [tR/hr) to 25 [LR/hr; within release limits. The S-18 vault survey will be included in a future report.

The drain line between the S-18 and S-15 sewer vaults (about 130 feet of sewer drain line) was removed because of the high potential for contamination as a result of S-18 and S-15 being contaminated, (although no contamination was detected inside the drain line after its removal).

The drain line was still disposed of as radioactive waste and a new drain line installed.

3

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GENERALATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 Soil samples were collected after removal of the asphalt and in the bottom of the trench.

Exposure rate scans inside the trench were conducted as well as exposure rate measurements 1 meter from the surface.

S-15 to S-13 Trench Sewer vault S-15 on GA's Main site was radiologically contaminated primarily with Cs-137, although Co-60 was found in lesser concentrations. Decontamination of the vault in-place was not considered to be a desirable option due to the extent of the contamination. Therefore, GA decided to remove and replace the vault. Beginning in November 2001, the S-15 sewer vault removal project was initiated. Prior to excavation, the asphalt between sewer vault S-15 and S 18 (upstream) was surveyed; no contamination was found. A photo taken during the disassembly of the S-15 sewer vault is provided in Figure 4.

The S-15 vault was removed. A sample of the sludge that had accumulated in the bottom of the outlet line was collected and analyzed and found to be contaminated with Cs-137, U-235, and thorium. Therefore, it was decided to remove the sewer drain line between S-15 and S-13 in sections until contamination levels were indistinguishable from normal background levels or sufficiently low to not pose a safety hazard.

The sewer line was initially removed in 25 foot sections and sludge samples collected from within the drain line. Radioactivity levels initially decreased, but after a few sections were removed, the activity levels began to increase. Larger (50 foot) sections were then removed instead of 25 foot sections. Sludge samples continued to be collected and analyzed. The isotopes detected where Cs-137, U-238, U-235, thorium, and Co-60.

After -300 feet of sewer drain line was removed, a large eucalyptus tree was found to be inhibiting the removal of the drain line. The tree was cut down and the nearby asphalt removed in order to remove the drain line. A photo showing the tree prior to it being cut down is provided in Figure 5 (the tree is located on the left side of the photo). During this process, a sewer vault which had previously been covered over with asphalt was unearthed. This vault had been invaded by the root system of the eucalyptus tree which had been cut down to gain access to the drain line. The root from the eucalyptus tree had entered the vault through the manhole lid and had grown and nearly completely filled, the sewer vault The root apparently acted as a dam/filter, and entrapped large quantities of sludge that had high levels of Cs-137, Co-60, uranium and thorium. A photo of the root (which was approximately 6 feet long and 3 feet wide) is shown in Figure 6. Radiation readings on the root were about 140 [tR/hr. A photo during the removal of the uncovered vault is provided in Figure 7. Also inside the vault was soil, rocks and other debris, which along with the vault, were also found to be contaminated. The vault and its contents were disposed of as low level radioactive waste.

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GENERALATOcMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 Upon later review, it was discovered that this vault appeared in older GA site drawings. The older drawings were reviewed to ensure that another similar vault did not exist. No other vaults could be found in the old drawings.

A total of seven (7) samples of tree roots, twigs, leaves and sawdust were collected from the radioactively contaminated eucalyptus tree. The gamma spectroscopy results are provided in Table 7 (sample #'s 35 through 41). The results for the sample of roots from the uncovered vault

(# 35 on Table 7) measured 65.32 +/- 5.46 pCi/g Cs-137 and 54.98 +/- 4.64 pCi/g thorium, 1.15 +

0.34 pCi/g U-235. A sample of tree roots had 1128 +/- 2282 pCi/total root sample of Cs-137 and 377.5 +/- 767 pCi/total root sample of thorium. As a result, the entire eucalyptus tree was moved from its initial location to a radioactive materials storage area and subsequently packaged as radioactive waste. A photo of the tree (cut up into sections) is provided in Figure 8.

Radiation readings inside the trench were at normal background levels after removal of the uncovered vault. The drain line downstream from this vault was found to contain quite a bit of contaminated sludge. The drain line was removed another -275 feet to the next sewer vault, S

13. This vault was found to be cracked and therefore also removed and replaced. In the interest of expediency, it was decided to also dispose of this vault as radioactive waste rather than survey it and go through the "release process".

A total of 28 sludge samples were collected from the inside of the sewer drain lines during removal of the lines. The approximate locations where these samples were collected are shown in Figure 10. The results are provided in the first two pages of Table 7. The highest result was at location 16. This sample of sludge was contaminated with uranium, thorium, Cs-137 and Co-60.

The Cs-137 concentration was 181.10 +/- 17.34 pCi/g. The Co-60 was 48.35 +/- 5.50 pCi/g, the U 238 value was 21.46 +/- 17.36 pCi/g, the U-235 value was 7.55 pCi/g and the total thorium (Th 232 and Th-228) was 65.14 +/- 12.97 pCi/g. All of the drain lines (and contained sludge) were disposed of as radioactive waste.

A total of 56 Post Drain Line Removal (PDLR) soil samples were taken after removal of the drain line trench in order to quickly establish whether contamination of the soil had occurred.

The locations where the post drain line samples were collected are shown in Figure 11 and the gamma spectroscopy results are provided in Table 8. Cs-137 was detected in some of the samples, the highest being 0.52 +/- 0.08 pCi/g (sample PDLR-47 on Table 8). Co-60 was not detected on any of the samples. Uranium and thorium concentrations were at, or near, normal background levels.

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+ GENFERALATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-i8 to S-13 Classification The portion of the excavation trench that contained the previously unknown sewer vault was classified as a Suspect Affected Area for radiological survey purposes due to the high levels of contamination found in the vault. The remaining portions of the excavation trench were classified as Non-Suspect Affected Areas.

Criteria for Release to Unrestricted Use The most likely source of radioactivity found in the lines removed from this excavation trench was low level radioactive discharges into the sanitary sewerage system from Building 25, GA's liquid waste processing facility. Liquids from other GA nuclear facilities were taken to this facility for treatment and possible disposal into the sewerage system. The NRC soil release criteria (above background concentrations) for radionuclides typically found on the GA site are as follows:

Release Criteria for Soils Enriched Uranium (U-234 + U-235) 30 pCi/g Thorium (Th-228 + Th-232) 10 pCi/g Depleted Uranium 35 pCi/g Cs-137 15 pCi/g Cs-134 10 pCi/g Co-60 8 pCi/g Eu-152 11 pCi/g If more than one radionuclide exists, the sum of the fractions of the concentrations (which must be less than or equal to 1) is calculated as follows:

Ci C--! <1 i Li Ci =

The average concentration levels of radionuclide I in the sample (above background).

L. =

The release criteria for radionuclide I.

Exposure Rate Guideline Exposure rates measured at 1 meter above the surface are not to exceed 10 LtR/hr above natural background levels.

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+ATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 Instrumentation and Background Measurements A list of instruments used during the radiological surveys is provided in Table 3. The table includes: (1) a description of the instrument, model number and its serial number, (2) a description of the detector (if applicable) and its serial number, (3) instrument ranges, (4) calibration due dates, (5) typical background readings and minimum detectable activity (MDA's, if applicable) and (6) calibration efficiencies (if applicable). All of the instruments used were calibrated semiannually and after repair, except for exposure rate meters which were calibrated quarterly.

Background Soil Concentrations of Concern Typical background concentrations measured by gamma spectroscopy in soil near the GA site have been established (at the 95% confidence level) and are provided in Table 4 along with a description of the locations where these samples were taken.

Exposure Rate Background Typical exposure rate background for GA's site using a Ludlum Model 19 micro R meter is 15 PR/hr (typical range is 12-18 WR/hr) measured at 1 meter from the surface of soil. This exposure rate can be measured south of Building 15 (an office building on the eastern portion of the GA site). Measurements taken offsite in 10 different locations (9 offsite and 1 onsite at a non impacted area near Building 15) over a period of 15 months also averaged - 15 [tR/hr (measured at 1 meter from the surface).

Background levels measured in a pit excavated in a Non-Impacted Area for use in comparison to trenches and pits on decommissioned sites are provided in Table 5. Background measurements are generally higher in pits/trenches than on flat surfaces. The range is typically 25 -27 ktR/hr.

Site Decommissioning Plan Requirements Compared to Surveys Performed Comparisons of the Site Decommissioning Plan requirements with the Final Surveys performed in relation to the percentage of surface area scanned, number of exposure rate measurements

(ýR/hr) and soil samples required and taken are provided as follows:

Exposure Rate Scanning and Fixed Measurements The Site Decommissioning Plan requires that exposure rate scanning be performed to provide 100% coverage in all affected areas and that fixed measurements be taken 1 per 4 m2 or 1 every 2 meters (1 meter from the surface). GA scanned almost 100% of the trench surfaces in the suspect and non-suspect affected areas and took fixed exposure rate measurements every 2 meters (1 meter from the surface).

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+GENERALATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-l3 Soil Sampling The Site Decommissioning Plan requires that soil samples be collected in trenches created during removal of potentially contaminated drain lines approximately every 5m, which corresponds to about 45 soil samples for a 772 foot (235 meter) trench. GA collected soil samples from the bottom of the trench at least 1 every 5 meters, and in fact, soil samples were collected at every -2 meters in most sections of the trench.

GA collected a total of 284 soil samples from inside the trench (from both side walls and from the bottom of the trench). These were in addition to 56 post drain line removal samples.

In addition, a total of 70 surface samples (not specifically required in the Site Decommissioning Plan) were collected.

Final Surveys Performed and Results Objectives and Responsibilities The objectives of the final survey plans were: (1) to demonstrate soil sample results were well below GA's approved release criteria for unrestricted use, and, (2) that the exposure rate measurements taken in these areas, measured at 1 meter above the surface, were less than 10

[tR/hr above background.

Survey Plan A Final Survey Plan was developed based on the radionuclides of concern detected in the sewer line samples, the potential for contamination, and the classification of the various areas. See Appendix A for the Final Survey Plan.

Surveys were taken in accordance with an approved survey plan by qualified Health Physics Technicians having a minimum of three years health physics experience. Soil samples were counted in GA's Health Physics Laboratory which maintains an effective QA program.

Every survey taken was documented on a daily basis to a worksheet/drawing showing the approximate locations surveyed/sampled. The documentation included the results of the measurements (including units), the technician's signature, date, instrument(s) used (including the model and serial number of both the ratemeter and detector), calibration due date, %

efficiency, background readings (if applicable) and any other pertinent information.

Preparation and Counting of Soil Samples Each of the soil samples taken was approximately 1 kilogram in mass. The samples were 8

I GENERAL ATOmICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 properly logged, labeled, tracked and packaged into plastic bags. The sampling locations were documented on a drawing. All debris (i.e., grass, rocks, sticks, asphalt and foreign objects) was removed from each sample. Each soil sample was individually crushed to reduce large lumps, dried, placed into tared marinelli beakers (filled to the top), weighed, sealed and transported to GA's Health Physics Laboratory.

Soil samples were analyzed in GA's Health Physics Laboratory with a Canberra Low Sensitivity Gamma Spectroscopy MCA System using a high purity germanium detector. The system is calibrated using NIST traceable standards and performance checked daily. Soil samples were counted for a minimum of 30 minutes each. A 30 minute count is sufficient to detect the radionuclides of concern at levels below GA's approved soil release criteria. Samples counted longer than 30 minutes are noted on the tables containing the soil sample results.

Exposure Rate Scanning Exposure rate scanning using a 2" x 2" NaI(T1) microR meter held within - 1" of the surface was performed to provide 100% coverage of all accessible areas of the trench. Approximately 33 feet of the 772 feet (-96%) of excavation trench was not available for surveys because this portion of the trench was traversed by a water main. This section of the trench (shown in Figures 12, 13 and

14) had to be immediately filled in after replacement of the sewer line to protect the water main from damage.

During the performance of the exposure rate scan, one (1) area with elevated levels and one (1)

Hot Particle were found and investigated as follows:

Investigation of 37 VR/hr Area of Trench The soil in a trenched area next to Building 25, which had levels as high as 37 itR/hr, was further investigated. The sand had higher radiation readings than the indigenous soil around it. It appears that the sand had been brought from a different location and used to surround a water main which was also in this area. Soil sample results of this sand showed no Cs-137, Co-60 or other radionuclides which would normally cause elevated readings above normal background levels (the maximum reading in the rest of the trench was 27 aR/hr). When a hole was dug in this sand and a 2" X 2" NaI(T1) detector was placed in this hole, the readings as high as 45 [LR/hr on the surface and inside the hole.

Further investigation of this area continued. Radioactive material and contaminated equipment inside Building 25 was considered, however, radiation levels outside the facility were only -25 [tR/hr, so Building 25 was ruled out as the source.

9

4+

GENERAL ATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 A large pile of this sand from this area was removed and placed alongside the pit in order for GA to determine if contaminated soil was behind this sand or perhaps another source was present. Exposure rate readings on the surface of the sand (once it was removed from the pit) were about 21 [R/hr. After a hole was dug into the sand and readings taken inside the hole, levels increased to -32 iR/hr. Gamma spectroscopy analysis of the three (3) sand soil samples collected in the elevated areas had only trace concentrations of Cs 137 and Co-60 as well as the naturally occurring thorium and uranium. The results are provided in Table 9 (results # 298-300 identified as EAT-1, EAT-2 and EAT-3). The results showed very low levels of Cs-137 (0.41 +/- 0.08 pCi/g) and Co-60 (0.03 +/- 0.01 pCi/g); well below the release criteria. No elevated levels of other isotopes were identified.

For comparison, exposure rate measurements of another "clean" pile of sand recently brought onsite to backfill pits and trench were collected. Surface readings were only 15 itR/hr. A hole in the sand pile was dug and another exposure rate measurement taken; the level did not change. A sample of this sand was analyzed by gamma spectroscopy (see last sample on Table 9 for results). Only normal background levels were found.

Radiation levels in the walls of the "cave area" created from the removal of the sand continued to measure about 30-35 [tR/hr. The higher than normal radiation levels (at contact) are most likely due to geometry factors, proximity to the asphalt surface and possibly natural activity.

Hot Particle Found During the surface scan of the open trench, a hot particle was found in the trench south of the uncovered vault at location 69 shown in Figure 12. The radiation level on the hot particle was 350 p.R/hr. This particle, along with the surrounding soil was removed and radiation levels immediately dropped to normal background levels for a trench (-25-28

[tR/hr). The hot particle and some of the soil was analyzed by gamma spectroscopy. The results showed high levels of Cs-137, Cs-134 and Eu-154 as shown in Table 8 (sample result #'s 29 and 30). Sample #30 was counted with additional soil to better match the geometry of the calibration standard. There was no breakage in the sewer drain line in this area and the soil was not discolored (which could indicate leakage from the drain line). GA believes that the hot particle probably fell out of the sewer line during removal.

The hot particle and soil removed with the particle were disposed of as low level radioactive waste.

A soil sample (post decontamination sample) collected in the area after the hot particle was removed, was also analyzed by gamma spectroscopy. Trace concentrations of Cs-10

+ GENERALA7Amics Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 137 were detected at 0.52 +/- 0.08 pCi/g (well below the limit of 8 pCi/g). See sample result # 297 on page T-43 of Table 9.

Following remediation of the Hot Particle, the maximum exposure level was 28 ItR/hr.

The elevated area near sewer vault S-15 remains elevated at contact, apparently due to geometry factors, proximity to the asphalt surface and higher than normal natural radioactivity. The radiation level at 1 meter from the surface of this sand was 25 to 28

[.tR/hr which is below the approved release criteria.

1.

The results of the surface scan in the trench between the S-15 and S-13 sewer vaults (shown in Figure 13) ranged from 15-30 [tRPhr; (the 37 WtR/hr level was found within a "cave" area and determined to be due to geometry factors, proximity to the asphalt surface and natural radioactivity).

2.

S-18 to S-15 Trench - The results of the surface scans in the trench between the S-18 and S-15 sewer vaults (shown in Figure 16) ranged from 20-30 [tR/hr; as compared to typical background readings inside pits/ trenches which range from 25 -27,týR/hr.

3.

Building 25 to S-15 Trench - The results of the surface scans in the trench between Building 25 and the S-15 sewer trench (shown in Figure 16) ranged from 21-28 [tR/hr; as compared to typical background readings inside pits/ trenches which range from 25 -27

[LRIhr.

Exposure Rate Fixed Measurements Fixed exposure rate measurements using a 2" x 2" NaI(T1) microR meter were taken every 2 meters (at 1 meter from the surface).

The exposure rate measurements ranged from 19-29 ýtR/hr in the trench between sewer vaults S 15 and S-13 sewer vault (see Figure 13), 19-23 [tR/hr, in the trench between sewer vaults S-18 and S-15 (see Figure 17), and 20-22 aR/hr in the trench between Building 25 and the S-15 sewer vault (see Figure 17). All results were < 10 WR/hr above a typical background for a trench.

Final Samples Collected and Analyzed A summary of the (1) number and type of final samples collected and analyzed by gamma spectroscopy, (2) the reason for the sample being collected, (3) the corresponding figure on which the sample locations can be found (if applicable), and (4) the corresponding table which provides the results are provided below:

11

+

GENERALATOMICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 70 Final Surface Samples - These samples were collected underneath the asphalt. This soil was not suspected of being contaminated, however, soil samples were taken to demonstrate that the soil meets the criteria for release to unrestricted use in support of a request to the NRC and State of California for release to unrestricted use.

The soil is currently piled next to the trench. GA is requesting that this soil be released to unrestricted use. The approximate locations where these soil samples were taken are provided in Figure 10. The gamma spectroscopy results of these soil samples are provided in Table 6. Cs-137 was measured in only 8 of 70 soil samples and Co-60 was measured in only 1 soil sample. The highest result was in soil sample VR-10 which had 1.76 +/- 0.20 pCi/g Cs-137 and 0.57 +/- 0.13 pCi/g Co-60 (the sum of fractions for this sample = 0.19 which is < 1). This sample was taken near the S-15 sewer vault next to Building 25. The next highest soil sample result measured 0.15 +/- 0.07 pCi/g Cs-137.

The uranium and thorium concentrations were at or near background values. Most of the results had no detectable Cs-137 or Co-60 (< 0.1 pCi/g) as shown in Table 6.

The results provided in the report demonstrate that the soil concentrations meet the NRC and State-approved criteria for release to unrestricted use. GA plans to: (1) use this soil for backfilling the trench, (2) use it for fill at other areas on GA's site, or (3) dispose of it in a local landfill.

2.

284 Final S-15 to S-13 Trench Soil Samples - In addition to the 70 soil samples collected from underneath the asphalt, 284 surface (0-6") soil samples were collected from the bottom and sides of the trench (every 2 meters except where noted in Figure 12) between the S-15 and S-13 sewer vaults. The approximate locations are shown in Figure 12. The gamma spectroscopy results are provided in Table 9.

In the Suspect Affected Area (the location where the uncovered vault was found), one sample was taken on each trench wall -6" from the bottom, - 1 meter from the bottom, and -2 meters from the bottom of the trench, as well as from the bottom of the trench itself. In the Non-Suspect Affected Area, one sample was taken on each trench wall -6" from the bottom and - 1 meter from the bottom, as well as the bottom of the trench (see Figure 12). The isotopic results (pCi/g) indicated that, in some samples, Cs-137 and Co 60 were present (when counted for 30 minutes), but the results were all well below the approved soil release criteria as summarized below. Naturally occurring U-238, U-235, Th-228, and Th-232 were present at levels that were not discernable from normal background levels.

12

+ GENERALATOmICS Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 U-238 U-235 Cs-137 Total Th Co-60 (pCi/g)

(pCi/g)

(Th-232 and Th-228)

(pCi/g)

High 2.26 0.36 0.81 5.29 0.20 Low ND ND ND 0.32 ND Average 0.28 0.03 0.02 2.64

<0.001 Nominal 2.26 0.18 0.09 4.00 ND

Background

Note:

1.

ND means not detected; <0.1 pCi/g Cs-137, <0.1 pCi/g Co-60, <3.0 pCi/g U-238, <0.3 pCi/g U-235.

2.

The high concentrations for each isotope did not occur in the same sample. No sample had a sum of fractions greater than 1.0 with background subtracted.

In a few of the soil samples, trace concentrations of the fission product Cs-137 was identified. The maximum concentration detected in the soil was 0.36 pCi/g with an average of 0.02 pCi/g; all results were well below the release limit of 15 pCi/g.

The highest U-235 result was 0.36 pCi/g (see Table 6) at the surface (0-6"); collected at location 4 (east side) as shown on Figure 12. Even if high enriched uranium was a contaminant, this level is far below the release limit of 30 pCi/g (U-234 and U-235).

All thorium results were at, or near, background levels and well below the release limit of 10 pCi/g. U-238 results were at, or near, background levels.

The activation product, Co-60 was identified in trace amounts in 4 out of 283 samples with the highest being 0.2 pCi/g; all results were far below the release limit of 8.0 pCi/g.

A strip of trench, approximately 6 meters in length (the location is shown in Figure 12),

was filled in to protect a water main. Soil samples were not taken in this area prior to backfilling the trench because of the immediate necessity to protect the water line. There is no reason to suspect that soil concentrations in this area would be higher than those concentrations found in other areas of the trench.

3.

8 Final S-15 to S-13 Trench Soil Samples - Eight (8) surface (0-6") soil samples were collected from the bottom of the trench (every 5 meters) between the S-18 and S-15 sewer vaults as shown in Figure 15. The gamma spectroscopy results are provided in Table 10.

13

+

GENERALATOm~c Final Radiological Survey Report For The Sewer Line Trench, S-18 to S-13 The results showed Cs-137 detected in only 1 of the 8 samples at a concentration of 0.21

+/- 0.07 pCi/g. Co-60 was also detected in only 1 of the 8 samples; at a concentration of 0.02 +/- 0.04 pCi/g. The thorium and uranium results were at or near normal background values. All results were well below the soil release criteria.

4.

2 Final Soil Samples from the Trench Between Building 25 and the S-15 Sewer Vault Two (2) soil samples were collected from the trench between Building 25 and the S-15 sewer vault. The approximate locations are shown in Figure 15. The results are provided in Table 10 (sample ID's 9 and 10). The results showed no detectable Cs-137 or Co-60.

The U-238 and U-235 value in one sample (#9) are higher than typically would be expected for normal background, however, the values are well below the allowable release criteria. The higher concentrations may be due to naturally occurring radioactivity.

5.

Roots, leaves and vegetation near uncovered vault area - Samples of residual roots in the vault excavation pit and pipe trench were taken along with clippings of other foliage in the area. Trace concentrations of Cs-137 (highest result was 1.09 +/- 0.19 pCi/g) were found in the residual roots but no detectable activity above background levels were found in the other foliage clippings (leaves and vegetation) as shown on Table 9 (sample #'s 301-304).

Root samples and foliage clippings were taken from a row of plants and trees near where the sewer vault was uncovered and adjacent to the roadway near the S-15 sewer vault.

Gamma spectroscopy results showed no detectable activity above normal background levels. See results for sample #Ws 304 and 305 in Table 9.

Conclusion Final radiological surveys and measurements, as well as the results of analyses of soil samples collected from the resulting -772 foot (-235 meter) trench and from the soil removed from the trench, as documented in this report, demonstrate that the "S-18 to S-13 trench" (including the S-15 to Building 25 trench) meet the approved criteria for release to unrestricted use.

14

Table 1:, JSNRC S ACCEPTABLEESRAECNATArNTEE.

Tabl 1: USN

'S: AC EPAL S

R AC CO M

A IO LEVELS.

Nuclides Average b~cr Maximum",'~

Removable',','

____(dpm/lOOcm 2)

(dpm/100 cm2)

(dpm/lOOcm2)

U-nat, 2 35 U, 23 8U, & associated decay products 5,000 a 15,000 a 1,000 a Transuranics, 226Ra, 22 8Ra, 23 0Th, 228Th, 231Pa, 100 300 20 227Ac, 1251, 1291 Th-nat, 232Th, 9 0Sr, 223Ra, 224Ra, 2 32 U, 1261, 1331, 1,000 3,000 200 1311 Beta/gamma emitters (nuclides with decay modes other than alpha emission or 5,000 15,000 1,000 spontaneous fission) except 90Sr and other noted above.

a Where surface contamination by both alpha-and beta/gamma-emitting nuclides exists, the limits established for alpha-and beta/gamma-emitting nuclides should apply independently.

b As used in this table dpm (disintegrations per minute) means the rate of emission by radioactive material as determined by correcting the counts per minute observed by an appropriate detector for background, efficiency, an geometric factors associated with the instrumentation.

c Measurements of average contaminant should not be averaged over more than 1 square meter.

For objects of less surface area, the average should be derived for each such object.

d The maximum contamination level applies to an area of not more than 100 cm 2 e

The amount of removable radioactive material per 100 cm 2 of surface area should be determined by wiping that area with dry filter or soft absorbent paper, applying moderate pressure, and assessing the amount of radioactive material on the wipe with an appropriate instrument of known efficiency. When removable contamination on objects of less surface area is determined, then pertinent levels should be reduced proportionally and the entire surface should be wiped.

f The average and maximum radiation levels associated with surface contamination resulting from beta-gamma emitters should not exceed 0.2 mRad/hr at 1 cm2 and 1.0 mRad/hr at 1 cm2, respectively, measured through not more than 7 milligrams per square centimeter of total absorber.

T-1

STable 2: STATE OF CA ACCEPTABLE SURFACE CONTAMINATION I FVE,SV*. I1 Nuclides'

.1 AveragebF I[

Maximumh,dj, Removablebl

__Nuc____ides________

" (dm/lJlc)

(dmItJOc...... j (dpm/100cm2 )

(dPM

00:

2 (dpm i100c mi) d i / 0 ý U-nat, 235U, 238U, & associated decay 5,000 15,000 1,000 products Transuranics, 226Ra, 228Ra, 230Th, 228Th, 100 300 20 231Pa, 227Ac, 12Si, 1291 Th-nat, 232Th, 90Sr, 223Ra, 224Ra, 232U, 1261, 1,000 3,000 200 133I, 1311 Beta/gamma emitters (nuclides with decay modes other than alpha emission or 5,000 15,000 1,000 spontaneous fission) except 9°Sr and other noted above a Where surface contamination by both alpha-and beta/gamma-emitting nuclides exists, the limits established for alpha-and beta/gamma-emitting nuclides should apply independently.

b As used in this table dpm (disintegrations per minute) means the rate of emission by radioactive material as determined by correcting the counts per minute observed by an appropriate detector for background, efficiency, an geometric factors associated with the instrumentation.

c Measurements of average contaminant should not be averaged over more than I square meter. For objects of less surface area, the average should be derived for each such object.

d The maximum contamination level applies to an area of not more than 100 cm 2.

e The amount of removable radioactive material per 100 cm2 of surface area should be determined by wiping that area with dry filter or soft absorbent paper, applying moderate pressure, and assessing the amount of radioactive material on the wipe with an appropriate instrument of known efficiency. When removable contamination on objects of less surface area is determined, then pertinent levels should be reduced proportionally and the entire surface should be wiped.

f The average and maximum radiation levels associated with surface contamination resulting from beta gamma emitters should not exceed 0.2 mrad/hr at 1 cm2 and 1.0 mrad/hr at 1 cm 2, respectively, measured through not more than 7 milligrams per square centimeter of total absorber.

Guidelines For Decontamination of Facilities and Equipment Prior to Release for Unrestricted Use or Termination of Licenses For byproduct, Source, or Special Nuclear Material, also known as "Decon-1 incorporated into GA's State of CA Radioactive Materials License.

T-2

ITABLE 3: S-18 to S-13 Sewer Drain Line Removal List of Instruments.

Instrument Detector Range Calibration Due Efficiency

Background

Description (cpm, pR/hr or mr/hr)

Date Ludlum Ludlum Model 44-10 Four Ranges 03-08-02 NA 2 inch x 2 inch Nal (TI) scintillator. Used for measuring Model 3 Nal (TI) Scintillator 0-500 p.R/hr 13-18 pr/hr (soil) external dose rates on the surface and at one meter.

S/N 147819 Gamma Detector S/N 153765 Ludlum Ludlum Model 44-10 Four Ranges 02-05-02 NA 2 inch x 2 inch Nal (TI) scintillator. Used for measuring Model 3 Nal (TI) Scintillator 0-500 pR/hr 13-18 plr/hr (soil) external dose rates on the surface and at one meter.

S/N 153590 Gamma Detector S/N 155190 Ludlum Ludlum Model 44-10 Four Ranges 04-09-02 NA 2 inch x 2 inch Nal (TI) scintillator. Used for measuring Model 3 NaI (TI) Scintillator 0-500 piR/hr 13-18 p~r/hr (soil) external dose rates on the surface and at one meter.

S/N 153551 Gamma Detector S/N 155109 Ludlum Ludlum Model 44-10 Four Ranges 03-08-02 NA 13-18 pr/hr (soil) 2 inch x 2 inch Nal (TI) scintillator. Used for measuring Model 3 Nal (TI) Scintillator 0-500 VR/fhr external dose rates on the surface and at one meter.

S/N 153311 Gamma Detector S/N 155594 CanberraLow Level Gas Flow N/A As needed 30%

Varies with Sample Canberra Model 2404 Low Level,/P gas proportional a/1 Counter Proportional Detector counting system used to count wipes for removable Model 2404 contamination. Results are usually reported as dpm/100cm2.

Canberra Gamma High Purity N/A As needed Varies with Varies with Sample Gamma Spectroscopy MCA system using a high purity Spectroscopy System Germanium Detector Sample Germanium detector.

T-3

Table 4 Gamma Spectroscopy Results of Background Soil (Surface) Samples Radionuclide Concentrations (pCi/gm) - Results + 2o-30 Minute Counts Sample

'37CS 60Co 228Th

.232 Th Total 23T 235U ID 661.6 keV 1173 keV peak 238.keV peak 911 keV peak Thorium 63.3 (92.7) 144 (186) keV peak 228Th + 232Th keV peak peak X-1 ND ND 0.71+/- 0.07 0.97 +/- 0.25 1.69 1.17 +/- 0.77 (0.13 +/- 0.06)

X-2 ND ND 0.90 +/- 0.13 1.49 +/- 0.31 1.49 1.91 +/- 1.18 (0.13 +/- 0.08)

X-3 0.06 +/- 0.04 ND 1.49 +/- 0.10 1.56 +/- 0.25 3.05 1.45 +/- 0.80 (0.23 +/- 0.09)

X-4 ND ND 1.52 +/- 0.23 3.22 +/- 0.61 4.74 3.74 +/- 2.18 (0.28 +/- 0.17)

X-5 ND ND 1.92 +/- 0.17 2.41 +/- 0.53 4.33 (4.49 +/- 1.64)

(0.32 +/- 0.16)

X-6 ND ND 1.02 +/- 0.08 0.96 +/- 0.23 1.99 1.31 +/- 0.80 (0.14 +/- 0.06)

X-7 0.13+/-0.08 ND 1.59 +/- 0.14 2.40+/-0.38 3.98 2.16+/- 1.48 (0.18+/-0.10)

X-8 ND ND 1.44 +/- 0.28 1.40 +/- 0.28 2.84 2.30 +/- 1.16 (0.14 +/- 0.09)

X-9 0.09 +/- 0.08 ND 0.89 +/- 0.10 1.27 +/- 0.31 2.15 1.59 +/- 1.05 (0.10 +/- 0.08)

X-10 ND ND 1.29+/-0.11 1.52+/-0.36 2.80 1.10+/-0.96 (0.16+/-0.08)

Notes:

1.

2.

3.

Soil samples were collected on 06/05/00 and 06/06/00 By Ed Rudgers off GA's site but close to GA.

Samples were counted 7/20/00 through 7/24/00 for 30 minutes (same count as the soil samples).

ND means:

< 0.1 pCi/g for Cs-137

< 0.1 pCi/g for Co-60 T-4

Table 5: Background Measurements in Pit Pipe Backgrounds LUDLUM MODEL 3 with 2"x 2" Nai (TI) Detector (jR/hr)

BACKGROUND PIT 14 15 Top View 15 14 14 Steel Ground

............................................I..........

25 2 5.

277 :--7 :

27

........................2 5 " '

........... 2 5 '

8 10 1'

19 29 3'

4' 5?

6'-

13 20 Micro-R per hour @ one meter from bottom center of pit 4ft 21 24 I A 23 22 Pipe Diameter 6 inches PVC Aluminum 12 13 1'-

22 2'

28 3'__

4' 5'

6'-

29 31 29 29 13 13 1'* 24 21 3,

4' 5'

6' 27 29 30 30 29 6

--- 4 ft All readings recorded in pRr (on surface of soil)

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

"14 w

E 14 T-5

Table 6: Surface Soil Sample Results, S-18 to S13 Sewer Line Removal Radionuclide Concen~trations (pClI~)

.Background~ Not Subtracted, 30. rinute count (ex~cept as noted)

U-238 U-235 Cs-137 Co-60 Total Thorium Other Isotopes Sample ID (3keV, 93 (144 keV, 186 (662 keV) 1(1 170 Th-228(23.8 keV used keV used when keV+l 330 keV), plus VR=Yault when 63 not 144 not keY) /2 )

Th-232(911 Removal present) present)

,.keY) pCi/(;

PCI/g pCifg.

pCi/g pGi/g pCi/g Isotope I

R-1 0.03 +/- 0.09 0.11 +/- 0.07 ND ND 2.93 +/- 0.68 ND 2

VR-2 ND 0.21 +/- 0.06 ND ND 3.42 +/-0.53 ND 3

VR-3 1.53 +/- 1.58 0.23 +/- 0.09 ND ND 3.68 +/- 0.78 ND 4

VR-4 (2hr) 2.87 +/- 1.68 0.38 +/- 0.07 ND ND 1.49 +/- 0.20 ND 5

VR-5 2.92 +/- 2.20 0.27 +/- 0.13 ND ND 4.02t

+/-0.76 ND 6

VR-6 (2hr) 2.94 +/- 1.65 0.37 +/- 0.06 ND ND 3.57 +/-t 0.48 ND 7

VR-7 ND 0.19 +/-0.11 ND ND 2.61 +/-0.55 ND 8

VR-8 1.02 +/- 1.13 0.19 +/- 0.08 ND ND 3.58 +/- 0.76 ND 9

VR-9 ND 0.17 +/-0.11 ND ND 4.22 +/-0.68 ND 10 VR-10 1.06 +/-1.13 0.18 +/-0.07 1.76 +/-0.20 0.57 +/-0.13 2.71+/-:t0.51 ND 1I IyR-11 1.27 +/- 1.32 ND ND ND 3.96 +/-t 0.76 ND 12 VR-12 1.54 +/-1.26 0.16.+/-0.07 0.11 +/- 0.05 ND 3.26 +/-0.54 ND 13 VR-13 ND 0.08 +/-0.09 0.05+/-t0.08 ND 4.15 +/-0.80 ND 14 VR-14 ND 0.10 +/-0.07 ND ND 1.88+/-t0.43 ND 15 yR-15 (2hr) 3.23 +/- 1.80 0.36 +/- 0.06 0.02 +/- 0.02 ND 3.38 +/- 0.43 ND 16 VR-16 (2hr) 2.80 +/-1.59 0.18 +/-0.18 0.04 +/-0.03 ND 3.28 +/-0.47 ND T-6

Table 6: Surface Soil Sample Results, S-18 to S-13 Sewer. Line Removal Radionuc*ide Concentrations (pCi/g)

__________Background Not Siibtracred, 30 minute count (except as noted)

U-238 U-235 Cs-137 Co-60 Totail Thorium Other Isotopes Sample ID (63 keV, 93 (144 keV, 186 (662 keY)

(11{Q70.

li-228(238 keV used keY Lused when keV. 13:30 keY), plus VR=Vault when 63 not 144 not keV) 12)

Th-232(91:

Removal present) present) kev) pCi/g' pCi/g pCifg pCi/g.

pigpCilgg Isotope 17 VR-17 ND ND ND ND 2.42 +/-0.63 ND 18 VR-18 ND 0.14 + 0.07 ND ND 3.05 +/-0.50 ND 19 VR-19 ND 0.19 +/- 0.09 ND ND 3.57 +/-0.63 ND 20 VR-20 1.30 +/-1.03 0.29 +/- 0.07 ND ND 3.27 +/-0.53 ND 21 VR-21 2.02 +/- 1.64 0.19 +/- 0.09 ND ND 3.24.+/- 0.62 ND 22 VR-22 ND 0.26 +/- 0.11 ND ND 3.62 +/- 0.87 ND 23 VR-23-(10hr) 4.31 +/- 2.32 0.27 +/- 0.08 ND ND 5.38 +/- 0.58 ND 24 VR-24 ND 0.13 +/- 0.10 ND ND 5.18 +/- 0.96 ND 25 VR-25 ND 0.14 +/- 0.10 ND ND 4.10:+/- 0.66 ND 26 VR-26 ND ND 0.15 +/- 0.07 ND 1.83 +/- 0.45 ND 27 VR-27 ND 0.10 +/- 0.09 ND ND 3.67 +/- 0.71 ND 28 VR-28 ND ND ND ND 3.04 +/- 0.70 ND 29 VR-29 ND 0.13 +/- 0.09 ND ND 3.54 +/- 0.65 ND T-7

Table 6: Surface Soil Sample Results, S.-18 to S-13 Sewer Line Removal Radioniuclide Co~ncvntrations,(pLug)

Backg round Not Subtra~cted, 30 n-dlnute count (ex~cept as noted)

U-238 U-235 Cs4137 Co-60 Total Thorium Other Isotopes Sample ID (63 keV, 93 (144 keV, 186 (662 ke.)

1(1170 Th-228(238 keV used keV used when keV+1330 ke.V), plu~s VR=Yault when 63 not 144 not

.keY)

/2)

Th-232(91 I Removal present) present) k.V) pCi/g pCi/g pCila-pCilg

.pCi/g pCilgý Isotope 30 VR-30 ND 0.12 t 0.08 ND ND 2.96 t 0.69 ND 31 VR-31 0.75 t 1.00 0.14 +/- 0.12 0.07 +/- 0.07 ND 3.48 t 0.76 ND 32 VR-32 ND ND ND ND 1.39 +/- 0.46 ND 33 VR-33 ND ND ND ND 2.25 +/- 0.15 ND 34 VR-34 ND 0.11 +/- 0.09 ND ND 2.57 t 0.63 ND 35 VR-35 ND ND ND ND 1.93 +/- 0.66 ND 36 VR-36 ND 0.03 +/- 0.07 ND ND 1.39 +/- 0.37 ND 37 VR-37 1.44 +/- 1.33 ND ND ND 2.89 +/- 0.62 ND 38 VR-38 ND 0.17 +/- 0.13 ND ND 3.99 +/- 0.90 ND 39 VR-39 ND ND ND ND 1.28 +/- 0.39 ND 40 VR-40 ND 0.13 +/- 0.10 ND ND 2.26 +/- 0.60 ND 41 VR-41 ND ND ND ND 2.10 +/- 0.52 ND 42 VR-42 ND ND ND ND 1.50:+/- 0.38 ND T-8

Table 6; Surface Soil Sample Reslt.*,

S-18 to S-13 Sewer Line Removal Radionuclide Concentrations (pC!/g)

___________Background Not Subtracted, 30 minute count (except as noted1)

U-238 Uý235 Cs-137 Co-60 TJotal Thorium Other Isotopes Sample ID (63 keV, 93 (1144 keV, 186 (662 keV)

[(1170 Th-228(2-3&

keV used keV used when keV+/-1330 k-eY), plus "VR=Vault when 63 not 144 not keV), 2}

Th-232,(911 Removal present) present)

Klev)

pCilg, pCilg pi Pcilg PCL'/g pCijg Isotope 43 YR-43 ND 0.16 +/- 0.12 ND ND 4.61 +/- 0.91 ND 44 VR-44 NID 0.06 +/-0.08 ND ND 1.65 +/-0.41 ND 45 VR-45-1 ND ND ND ND 3.18 +/-0.66 ND 46 VR-45-2 2.08 +/- 1.66 0.20 +/-0.09 ND ND 3.45 +/- 0.61 ND 47 VR-46-1 ND ND ND ND 3.07 +/- 0.70 ND 48 VR-46-2 ND

0. 14+/-0.09 ND ND 3.60 +/-0.74 ND 49 VR-47 ND 0.05+/-0.03 0.13 +/- 0.05 ND 1.76 +/- 0.38 ND 50 YR-48 ND 0.11+/-0.07 ND ND 1.51 +/- 0.36 ND 51 YR-49 ND 0.25+/-0.10 ND ND 3.09 +/-0.63 ND 52 VR-5O ND 0.09+/- 0.09 ND ND 4.21 +/- 0.83 ND 53 YR-51 0.35 +/- 1.05 0.16+/-0.11 ND ND 3.23 +/- 0.66 ND 54 VR-52 ND 0.09+/-:t0.07 ND ND 2.84 +/-0.71 ND 55 VR-53 ND 0.06 +/- 0.07 ND ND 2.82 +/- 0.58 ND T-9

A v rA: * r*5 p :p' : r¸ : -*

Table 6: Surface Soil Sample Results, S-18 to S-13 Sewer Line Removal Radionuc~lide Conicentrations (pCi/g)~

Backg round Not Siubracted, 30 rrinute count (except a noted)

U-23$

U-235 CS-137 Co-60 Total.Tho.rium Other Isotopes Sample 11)

(63 keV, 93 (144 keY, 186 (662 keV) 1(1170 Th-~281(23$.

keV used keY used when keY+1330

.keV), plus VR=Vault when 63 not 144 not keV)/21 T.h-23.2(91 Removal present) present) 1V pGi/g pCilg pCi/g Pi/8

~

pCi/g pCi/g Isotope 56 VR-54 ND 0.13 +/- 0.07 ND ND 3.11 +/- 0.60 ND 57 VR-55 ND 0.19 +/- 0.09 ND ND 4.88 +/- 0.97 ND 58 VR-56 ND 0.24 +/- 0.10 ND ND 3.53 +/- 0.59 ND 59 VR-57 ND 0.15 +/- 0.08 ND ND 3.42:+/- 0.66 ND 60 VR-58 ND ND ND ND 3.72 +/- 0.65 ND 61 VR-59 ND ND ND ND 2.23 +/- 0.17 ND 62 VR-60 ND 0.19+/-:1 0.09 ND ND 3.96:+/- 0.68 ND 63 VR-61 1.67 +/- 1.82 0.19 +/- 0.13 ND ND 4.75 +/- 0.85 ND 64 VR-62 ND 0.15+/- 0.10 ND ND 3.20 +/- 0.67 ND 65 VR-63 ND 0.06 +/- 0.07 ND ND 1.36 +/- 0.36 ND 66 VR-64 ND 0.11 +/- 0.08 ND ND 2.17 t 0.44 ND 67 VR-65 ND ND ND ND 1.81 +/- 0.54 ND 68 VR-66 ND 0.11 +/- 0.06 ND ND 2.04+/- 0.39 ND T-10

Table 6: Surface Soil Sample Results, S-18 to S-13 Sewer Line Removal Radionuclide Concentra*tions (pCi/g).

Background Not Subtýracted, 30 miAnute count (except as n~oted)

U-238 U-.235 Cs4137 Co-60 Total Thoriumi Other Isotopes Sample ID (63 keV, 93 (144 keV, 186 (662 keV) 1(1170 Thl228(238 keV used keV used when lke.V+/-330 keY), plus VR Vault when 63 not 144 not ke.) 12)

Th-232(911 Removal present) present) k"eV) pCi/g pClg pCi/g pCi/g pcgi/

pci/

{:

Isotope 69 VR-67 ND 0.05 +/- 0.06 ND ND 1.23 +/- 0.43 ND 70 VR-68 ND 0.09 +/- 0.07 ND ND 1.88 +/- 0.37 ND 71 VR-69 ND 0.14 +/- 0.08 ND ND 1.30 +/- 0.55 ND 72 VR-70 ND 0.14 +/- 0.08 ND ND 3.45 +/- 0.61 ND

1.

ND = Not detected, <0.1 pCi/g Cs-137, <0.1 pCi/g Co-60, <3.0 pCi/g U-238, <0.3 pCi/g U-235.

2.

Surface soil is currently piled next to the excavation trench. GA is requesting that this soil be released to unrestricted use. The soil will either: (1) be placed back into the trench, (2) be used at other areas on GA's site, or (3) be disposed of at a local landfill area.

T-1 1 Notes:

Table 7: Initial Samples, S-15 to S-13 Sewer Drain Line and Sewer Va**It Sludge Sample Results Radion~uclide Concentraitions (pCi/g)

__________Background Not Subtracted, 3 0 minute count (except as noted)

U-238 U-235 Cs-137 Co-60 Tot8i*l Torwiun Other Isotopes (63keV, 93 (l44keV,186 (662 keV)

ý((1170 Th-228(238 used keV used when keV+1330 keV), plus when 63 not 144 not keV) /2 I Th-232(91.1 Sample IDi present) present) 1eV) pCi/g pCi/gr pCi/g pCiig jpCifg pCilg Isotope 1

Line-1 0.64 +/- 2.02 0.43 +/- 0.27 43.78 +/- 3.79 3.33 +/- 0.49 1.83 - 0.49 0.61 +/- 0.13 Cs-134 2

Line-2 ND 0.76 +/- 0.55 10.69 +/- 1.21 0.18 +/- 0.29 10.42 2.63 ND 3

Line-3 ND 0.36 +/- 0.27 33.01 +/- 2.95 1.11 +/- 0.36 3.82 1.67 0.47 +/- 0.25 Cs-134 4

Line-4 ND ND 15.27 +/- 1.56 0.41 +/- 0.29 2.35 - 0.72 0.28 +/- 0.14 Cs-134 5

Line-5 ND ND 5.80 +/- 0.67 ND ND ND 6

Line-5a ND ND 9.51 +/- 1.04 0.26 +/- 0.21 1.00 +/- 0.67 ND 7

Line-6 ND ND 1.30 +/- 0.25 ND 0.40 +/- 0.20 ND 8

Line-6a ND 0.18 +/-0.13 9.66+/--0.92 0.58+/-0.17 3.26+/--0.94 ND 9

Line-8 4.61 +/- 4.22 0.88 +/- 0.86 21.40 +/- 1.92 1.08 +/- 0.27 9.46 +/- 2.14 0.22 + 0.09 Cs-134 10 Line-9 ND 0.13+/-0.10 15.15+/- 1.32 1.29+/-0.20 2.21 +/--0.63 0.12+/-0.04 Cs-134 11 Line-10 3.88 +/- 3.87 6.35 +/- 2.13 41.56 +/- 3.69 2.26 +/- 0.46 17.74 +/- 2.92 ND 12 Line-11 ND 1.26 +/--2.33 14.42 +/- 1.52 1.23 +/- 0.42 19.66 +/- 3.45 ND 13 Line-12 ND 20.42 +/- 4.40 23.95 +/- 2.50 7.74 +/- 1.27 41.32 +/- 6.69 ND T-12

Table 7: Initial Samples, S-15 to S-13 Sewer Drain Line and Sewer Vault Sludge Sample Results Radionuclide Concentrations (pCi/g),

Background Not Sutbtracted, 30 minute~ count (except as noted)

U-238 U-235 Cs4137 Co-60 Total Thorium Other Isotopes (63keV, 93 (l44keV,186 (662 keV)

{(I 170 Th-228(238 4keY used keV u~sed wvhen keV+1330 keV), plus when 63 not 144 not keV) /21 Th-232(911 Sample ID present) present) 1eV) pCi/g pCilg pCilg pCi/g pCilg pCilg Isotope 14 Line-13 ND 1.28 +/-0.75 32.92 +/-3.49 2.05 +/-0.75 11.51 +/-4.49 ND 15 Line-14 ND 5.01 +/- 4.02 49.01 +/- 5.00 3.81 +/- 1.18 26.30 +/- 5.97 ND 16 Line-i15 7.45 +/- 6.78 3.72 +/- 3.06 97.61 +/- 8.66 27.06 +/- 2.95 27.88 +/- 5.95 ND 17 Line-16 21.46 +/-

7.55 +/-6.05 181.10 +/- 17.37 48.35 +/-5.59 65.14+/- 12.97 ND 17.36 18 Line-17 N D 9.45 +/-4.51 89.11++/-9.11 13.81++/-2.29 26.15+7.92 ND 19 Line-18 ND 4.89 +/-3.01 38.93 +/-6.20 ND 11.90+4.32 ND 20 Line-19 ND 4.19 +/-4.26 23.75 +/-2.69 1.56 +/-0.67 18.06+/-4.40 ND 21 Line-20 ND 5.36 +/-4.76 60.15 +/- 6.90 3.01 +/- 1.45 32.77+ 11.45 ND 22 Line-21 ND 3.64 +/- 1.00 29.36 +/-3.57 1.16 +/-0.85 6.28+/- 1.75 ND 23 Line-22 ND 2.41 +/-0.67 32.66++/-3.28 1.47 +/-0.51 5.32 +/-2.11 ND 24 Line-23 ND 3.04 +/- 1.77 40.29 +/- 5.59 2.93 +/- 1.35 8.05 +/- 2.48 ND 25 Line-24 ND 5.84 +/- 1.95 6.54 +/- 1.57 ND 10.71 +/- 5.74 ND T-13

Table 7: Initial Samples, S-15 to S-13 Sewer Drain Line and Sewer Vault Sludge Sample Results Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 minute count (except as noted)

.U-238 U.1-235 Cs-137 Co-60 Total Thorium Other Isotopes (63keV,93 (144keV,186 (662 keV)

(1 170 Th-228(238 keV used keV used when keV+1330 keV), plus when 63 not 144 not keV)/2

~

Th-232(911 Sample ID present) present) keV) pCilg pCilg pCig pPCig pCi/g Isotope 26 Line-25 ND 4.87 +/- 2.88 40.39 +/- 3.95 3.50 +/- 0.78 19.84 +/- 3.87 ND 27 Line-26 ND 3.95 +/- 3.42 27.52 +/- 3.20 1.47 +/- 0.75 15.37 +/- 4.62 ND 28 Line-27 ND 4.54+/- 1.54 24.56+/-3.37 3.03-+/- 1.14 5.27+/- 1.52 ND 29 69-Hot ND ND 5.3e4 +/- 5.9e3 ND ND 211.50 +/- 27.09/

Cs-134/

Particle 786.7 +/- 98.84 Eu154

+ 31 g soil 30 69 Hot ND ND 1.59e4 +/-

ND ND 58.46 +/- 6.55/

Cs-134/

Particle 1.34e3 217.4 +/- 22.7 Eu154

+ 138g soil 31 V-13 Vault ND 0.31 +/- 1.40 1.31 +/- 0.31 ND 7.60 +/- 2.05 ND 32 V-13 Vault 1.29 +/- 0.87 0.82 +/- 0.40 1.36 +/- 0.14 0.13 +/- 0.05 4.93 +/- 0.71 ND 33 V-13 upstream 8.99+/- 14.10 48.11 +/- 13.63 ND ND 154.39+24.60 ND 34 Uncovered ND 3.44 +/- 2.16 70.30 +/- 6.41 20.41 +/- 2.43 6.69+/- 1.56 ND Vault 35 Uncovered ND 1.15 +/- 0.34 65.32 +/- 5.46 54.98 +/- 4.64 0.79 0.45 ND Vault Roots-I IIII

_II T-14

Table 7: Initial Samples, S-15 to S-13 Sewer Drain ne and Sewer Vault Sludge Sample Results Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 minute cou~nt (except, as noted)

U-238 U-235 Cs-137 Co-60 Total Thorium Other Isotopes (63keV, 93 (l44keV,186 (662 keV)

{(I 170 Th-228(238 keV used keV used when keV+1330 keV), plus when 63 not 144 not keV) /21 Thi;232(911 Sanmple ID present) present) keV) pCi/g pCilg p~ilg pCi/g pCilg pCiig Isotope 36 Uncovered ND 1.08 +/- 0.16 65.31 2.73 55.02 +/- 2.33 0.84 +/- 0.24 ND Vault Roots-2 37 Tree Leaves ND ND 0.65 + 0.28 ND 0.63 +/- 0.35 ND 38 Tree Saw Dust ND ND 0.68 + 0.10 ND 0.85 +/- 0.08 ND The following results are in pCi /Total Sample 39 Tree twigs&

ND ND 46.29 +/- 99.49 ND 38.20 +/- 91.49 ND roots-1 40 Tree twigs&

ND ND 331.00 ND ND ND roots-2 672.70 41 Tree Roots ND ND 1128.0 +/-

ND 377.50+

ND 2282.0 767.00 T-15

Notes 1.

ND = Not detected, <0.1 pCi/g Cs-137, <0.1 pCi/g Co-60, <3.0 pCi/g U-238, <0.3 pCi/g U-235

2.

Sewer Drain Lines and Sewer Vaults S-15, S-13, and the Uncovered Vault were disposed of as radioactive waste.

3.

The contaminated tree, including the removed roots, twigs, leaves, and saw dust, created by cutting the tree up, were disposed of as radioactive waste.

4.

The Hot Particle was found in a different location than the uncovered vault. It was removed, including the soil around it, and disposed of as radioactive waste.

T-16

Table 8: Post Drain Line Removal, S-18 to S-13 Sewer Line Removal Pipe Trench, Soil Sample Results Radtionuclide Concentrations (pCi/g)

Background Not Su~btracted,_30 minute count (except as noted)

"U-238 U-235 Cs]37 Co-60 Totail Thowrium Other Isotopes Sample ID (63 keV, 93 (144 keV,186 (662 keV)

((*1170 Th-228(238 PDLR Post keV used keV used when keV+1330 keV), plus Drain Line when 63 not.

144 not keY) 12ý T1'-232(9i1 Removat present) present)

IeV) pCi.g pC,.g pCi/g pCi/g pCi.,_

pCi/.

Isotope 1

PDLR-1 (2hr) 2.84 +/- 1.65 0.21 +/- 0.26 ND ND 4.29 +/- 0.60 ND 2

PDLR-2 (2hr) 2.31 +/- 1.42 0.09 +/- 0.14 ND ND 3.46 +/- 0.49 ND 3

PDLR-3 0.62 +/- 0.89 0.18 +/- 0.08 ND ND 2.85 +/- 0.63 ND 4

PDLR-4 (2hr) 2.28 1.34 0.34 +/- 0.06 ND ND 3.43 +/- 0.06 ND 5

PDLR-5 ND 0.24 +/- 0.10 ND ND 3.52 +/- 0.66 ND 6

PDLR-6 (2 hr) 1.88+/- 1.10 0.30 +/- 0.07 ND ND 3.68 +/- 0.49 ND 7

PDLR-7 1.04 +/-1.00 0.24 +/- 0.11 ND ND 3.41 +/- 0.70 ND 8

PDLR-8 2.04:L 1.52 0.24 +/- 0.11 ND ND 3.65 +/- 0.69 ND 9

PDLR-9 1.17 +/- 1.01 0.23 +/- 0.08 ND ND 1.95 +/- 0.55 ND 10 PDLR-10 ND ND 0.37 +/- 0.10 ND 2.12 +/- 0.55 ND 11 PDLR-11 ND ND 0.12 +/- 0.06 ND 1.39 +/- 0.13 ND 12 PDLR-12 ND ND ND ND 1.84 +/- 0.50 ND 13 PDLR-13 1.17 +/- 1.41 0.22 +/- 0.11 ND ND 3.92 +/- 0.68 ND 14 PDLR-14 (2 hr) 3.51 +/- 1.98 0.36 +/- 0.22 0.03 +/- 0.03 ND 3.68 +/- 0.53 ND 15 PDLR-15 (2hr) 2.22 +/- 1.32 0.33 +/- 0.05 0.11 +/- 0.03 ND 3.68 +/- 0.50 ND 16 PDLR-16 ND 0.12 +/- 0.09 ND ND 3.74 +/- 0.82 ND 17 PDLR-17 (2hr) 3.88 +/- 2.18 0.39 +/- 0.07 ND ND 3.66 +/- 2.96 ND 18 PDLR-18 ND ND 0.06 +/- 0.04 ND 1.07 +/- 0.32 ND T17

Table 8: Post Drain Line Removal, S-18 to S-13 Sewer Line Removal Pipe Trench, Soil Sample Results Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 minute count (except as noted)

U-238 U-235 Cs-137 Co-60 Total Thorium' Other Isotopes Sample ID (63 keV, 93 (144 keV,186 (662 keV)

((*l170 Th-228(238 t

PDLR = Post keV used keV used when keV+1330 keV), 'plus Drain Line when 63 not 144 not keV) /2)

Th-232(91 1 Removal present) present) keV) pCilg Z:,~igp~l pCi/g pCi/g, pCi/g Isotope 19 PDLR-19 ND ND 0.16 +/- 0.07 ND 1.95F +/-0.55 ND 20 PDLR-20 ND 0.06 +/- 0.05 ND ND 1.66 +/- 0.36 ND 21 PDLR-21 ND ND ND ND 1.11 +/- 0.33 ND 22 PDLR-22 ND ND ND ND 1.98 +/- 0.18 ND 23 PDLR-23 ND ND 0.05 +/- 0.05 ND 0.61 +/- 0.16 ND 24 PDLR-24 ND ND ND ND 1.58 +/- 0.16 ND 25 PDLR-25 ND 0.13 +/- 0.09 ND ND 1.39 +/- 0.37 ND 26 PDLR-26 ND 0.04 +/- 0.05 ND ND 1.57 +/- 0.42 ND 27 PDLR-27 ND ND ND ND 1.26 +/- 0.33 ND 28 PDLR-28 ND ND ND ND 1.41+/- 0.13 ND 29 PDLR-29 ND ND ND ND 0.97 +/- 0.32 ND 30 PDLR-30 ND ND ND ND 1.08 +/- 0.34 ND 31 PDLR-31 ND ND ND ND 1.10 +/- 0.09 ND 32 PDLR-32 ND ND ND ND 2.51 +/- 0.52 ND 33 PDLR-33 ND 0.06 +/- 0.04 ND ND 0.81 +/- 0.25 ND 34 PDLR-34 ND 0.06 +/- 0.04 ND ND 0.74 +/-: 0.23 ND 35 PDLR-35 ND 0.05 +/- 0.04 0.04 +/- 0.04 ND 1.10 +/- 0.29 ND 36 PDLR-36 ND 0.07 +/- 0.04 ND ND 1.07 +/- 0.27 ND T18

Table 8: Post Drain Line Removal, S-18 to $413 Sewer Line Removal Pipe Trench, Soil Sample Results "Radionuclide Concentrations (pCi/g)

Background Nrot Subtracted, 310minute count (except as noted)

U-238 U3-235 Cs-.37 Co60 Total Thorium Other Isotopes Sample ID (63 keV, 93 (144 keV,186 (662 keV)

{(l 170 Th-228(238 PDLR = Post keV used keV used when keV+1330 *

]eV), plus Drain Line when 63 not 144 not keV) 12}

Th-232(91i1 Removal present) present) keY) pCi/g pCi/g-pCilg pCi/g pCi/g pCilg Isotope 37 PDLR-37 ND ND ND ND 0.39 +/- 0.14 ND 38 PDLR-38 ND 0.08+/-*+/-0,07 0.17 +/- 0.08 ND 2.04 +/- 0.65 ND 39 PDLR-39 ND ND 0.08 +/- 0.04 ND 1.51 +/- 0.47 ND 40 PDLR-40 ND ND ND ND 0.37 +/- 0.10 ND 41 PDLR-41 ND ND ND ND 2.10 +/- 0.52 ND 42 PDLR-42 ND 0.03 +/- 0.04 ND ND 0.96 +/- 0.30 ND 43 PDLR-43 ND 0.04 +/- 0.04 ND ND 1.03 +/- 0.32 ND 44 PDLR-44 ND 0.04 +/- 0.03 0.03 +/- 0.03 ND 0.81 +/- 0.26 ND 45 PDLR-45 ND 0.10 +/- 0.05 ND ND 2.47 +/- 0.49 ND 46 PDLR-46 ND 0.04 +/- 0.04 ND ND 1.04 +/- 0.28 ND 47 PDLR-47 ND 0.08 +/- 0.05 0.52 +/- 0.08 ND 1.32 +/- 0.29 ND 48 PDLR-48 ND ND ND ND 0.78 +/- 0.28 ND 49 PDLR-49 ND ND ND ND 1.06 +/- 0.47 ND 50 PDLR-50 ND ND ND ND 2.34 +/- 0.44 ND 51 PDLR-51 ND 0.05 +/- 0.08 ND ND 2.25 +/- 0.63 ND 52 PDLR-52 ND ND 0.37 +/- 0.08 ND 2.19 +/- 0.23 ND 53 PDLR-53 ND 0.10 +/- 0.09 ND ND 2.82 +/- 0.58 ND 54 PDLR-54 ND ND ND ND 0.48 +/- 0.07 ND T19

Table 8: Post Drain Line Removal, S-18 to S-13 Sewer Line Removal Pipe Trench, Soil Sample Results Radionuclide Concentrations (pCi/g)

BackgroundNot Subtracted, 30 minute count (ex.cept as noted)

U-238 -U235 Cs-137 Co-60 Total Thorium Other Isotopes Sample ID (63 keV, 93 (144 keY, 186 (662 key)

( (1170 Th-228(238 PDLR =Post keV used keV used when keV+1330 key), plus Drain Line when 63 not 144 not keV) /21 Th-232(91 1 Removal present) present) keV) pCilg pCilg pCi/Qs pCi/g pCilg pCilg I

sotope 55 PDLR-55 ND ND ND ND 1.40 +/- 0.38 ND 56 PDLR-56 ND 0.07 +/- 0.05 ND ND 1.40 +/- 0.33 ND Note: ND = Not detected, <0.1 pCi/g Cs-137, <0.1 pCi/g Co-60, <3.0 pCi/g U-238, <0.3 pCi/g U-235 T-20

Table 9: S-18 to S-13 Sewer Drain Line Trench Final Soil Sample Results Radionuclide~ Concentrations (pCi/g).

B~ackground Not Subtr~acted, 30 min. cou~nt (except as noted)

U3-238 U3-235 CS-137

.Co-60~

Total Thorium Other Isotopes Exposure (63keV, 93 (144keV,186 (662 keY)

((1170,i Th-228(238 >

Rate @ 1 used keV used when

.keVi433O keY), Plus i mfrom when 63 not 144 not 1e~V) /21

,Th-232(9 11 trench present) present)

,keY) bottom Sample ID in [iR/r PCi/

pCi/g pCilg' pCilg pCig

'PC!/-

Isotope 1

1B 0.40 +/- 0.72 0.09 t 0.06 ND ND 1.55 +/- 0.40 ND 21 2

1E ND 0.21+/- 0.12 ND ND 3.73 +/- 0.72 ND 3

1W ND 0.14 +/-0.08 ND ND 4.33 +/- 0.70 ND 4

2B ND 0.06 +/-t- 0.07 ND ND 1.07 +/- 0.29 ND 20 5

2E ND 0.18 +/- 0.13 ND ND 3.81 +/- 0.78 ND 6

2W ND 0.14 +/- 0.12 ND ND 5.22 +/- 1.00 ND 7

3B 0.56 +/- 0.49 0.05 +/- 0.17 ND ND 1.32 +/- 0.37 ND 19 8

3E 1.23 1.47 ND ND ND 3.99 +/- 0.76 ND 9

3W 2.10 +/- 2.00 0.12 +/- 0.12 ND ND 3.80 +/- 0.76 ND 10 4B ND 0.07 +/- 0.06 ND ND 1.34 +/- 0.32 ND 20 11 4E (2hr) 1.28 +/- 0.91 0.15 +/- 0.05 ND ND 4.24 +/- 1.04 ND 12 4W ND 0.11 +/-10.08 ND ND 1.76 +/- 0.42 ND 13 5B ND 0.08+/- 0.04 0.20 +/- 0.05 ND 1.27 +/-0.31 ND 20 14 5E ND 0.12 +/- 0.09 0.07 +/- 0.06 ND 3.26 +/-0.63 ND 15 5W ND ND ND ND 0.73 +/-0.25 ND 16 6B ND ND 0.32 +/- 0.06 ND 1.50 +/-0.33 ND 19 17 6E 0.77 +/- 1.06 0.17 +/- 0.08 ND ND 4.31 +/- 0.83 ND 18 6W ND 0.19 +/- 0.11 ND ND 5.20 +/- 0.94 ND T-21

.Table 9: S-18 to S43 Sewer Drain Line TrenchFinal Soil Sample Results R~adionuclide Con~centrations pCi/g,)

B~ackground Not Subtracted, 30 mn~i.

count (except as noted)

U-238 U-235 Cs-137 Co-60 Tota Thorium Other Isotopes Exposure (63keV, 93 (l44keV,186 (662 ke.V)

t. (1170 TFh-228(238 Rate @ I keV used keV used when

.eV+

1330 keV; plis m from when 63 not 144 not keV) /2)1 Tb-232(911, trench present) present) keV'),bottom Sample ID in j[LR~ir pCilg pCilg pCi/g pCilgr pGil pCi/g Isotope 19 7B ND 0.09 +/-0.10 0.07 +/-0.05 ND 2.88 +/-0.58 ND 18 20 7E ND ND ND ND 3.99 +/-0.74 ND 21 7W 1.53 +/-1.34 0.15 +/-0.08 ND IND 3.95 +/-0.68 ND 22 8B ND 0.05 +/-0.05 0.16 +/-0.06 ND 1.97 +/-0.40 ND

-19 23 8E ND 0.23 +/-0.11 ND ND 4.50+/-:t0.87 ND 24 8W ND 0.13 +/-0.08 ND ND 3.64 +/-0.61 ND 25 9B ND ND 0.04+/-t0.05 ND 1.69 +/-0.48 ND 19 26 9E ND ND ND ND 4.73 +/- 0.90 ND 27 9W 0.98 +/-1.33 0.18 +/-0.11 ND ND 4.44 +/-0.76 ND 28 1013 0.84 +/- 0.79 0.17 +/- 0.09 ND ND 1.96 +/- 0.49 IND 19 29 108 ND 0.12 +/- 0.09 IND ND 4.04 t 0.79 ND 30 low ND ND ND ND 4.40+/-t0.95 ND 731ý 1113 ND ND 0.08 +/-0.10 ND 2.75 +/-0.60 ND

-18 T-22

I*

I Table 9: S-18 to S-13 Sewer Drain Line Trench Fina Soil Sample Results U-235 (l4-4keV,186 k~eY used when 144 not present)

R'adion"uclide Concentrations (pC )

Backg'round Not Sub7tracted, 30 1111. count (exc~ept a.s noted)

I C.-137.

(662 keV)

I

<Co.60

'((1170 keV+133O0 lkeV)/21 Total Thorium Th-228(238 keV), plus Th.232(91 1 keV)K I

I

.t A

I PciIg PCi/g-pCikg nCiY

Other Isotopes nC9Ar 32 HIE ND ND ND ND 3.97+/-t 0.68 ND 33 11W ND ND ND ND 0.32 +/- 0.09 ND 34 12B ND ND ND ND 1.06 +/- 0.30 ND 18 35 12E ND 0.06 +/- 0.12 ND ND 4.25 +/- 0.82 ND 36 12W ND 0.14 +/- 0.08 ND ND 2.95 +/- 0.65 ND 37 13B 0.95 t 0.95 0.06 +/- 0.05 ND ND 1.67 +/- 0.41 ND 19 38 13E 2.26 +/- 1.69 0.15 +/- 0.07 ND ND 4.13 +/- 0.82 ND 39 13W ND 0.14 +/- 0.07 ND ND 3.10 +/- 0.55 ND 40

14B3K,

,~~,

41 14W3i.

V 43

15B3,

7.

,.,,.c 44

,E

-K*,

45 15W K.

T-23 I

Sample ID U-238 (63keV,93 keV used when 63 not present) pCi/g Exposure R~ate @ I mi from trench bottom in [iR/hr Icni",

D r

53 18E ND ND ND ND 1.27 +/- 0.36 ND 54 18W 1.10 +/-1.40 ND ND ND 4.50+/-0.78 ND 55 19B ND ND ND ND 1.63 +/- 0.45 ND 21 56 19E ND ND ND ND 3.56 +/- 0.72 ND 57 19W ND ND ND ND 4.22 +/- 0.85 ND 58 20B ND ND ND ND 1.89 +/- 0.42 ND 24 T-24

Table 9: S-18 to S:13 Sewer Drain Line Trench Final Soil Sample Results I

p U-235 (144keV,186 keV used when 144 not present)

Radionuclide Concentrations (pCi/g)

Back~ground Not Subtracted, 30 mmn count (except as noted)

,Cs-137 (662 keV)

Co-60

[01170 keV+1330.

keV) 121~

Total Thoriux Im Th..22$(238 keV), plus,,

Th-2,32(91 11 keV)

T 1

r V

q pCi/g-pCilg pCilg PCilg pCij/

Other Isotopes ISOtoDe 59 20E ND ND ND ND 1.06 +/- 0.32 ND 60 20W ND ND ND ND 1.72 +/- 0.42 ND 61 21B 0.54 +/- 0.55 ND ND ND 1.41 +/-0.37 ND 23 62 21E ND 0.04 +/- 0.06 ND ND 1.26 +/- 0.33 ND 63 21W ND 0.06 +/- 0.07 ND ND 1.69 +/- 0.46 ND 64 22B ND ND ND ND 1.43+/- 0.37 ND 22 65 22E ND 0.05 +/- 0.06 ND ND 1.25 +/- 0.27 ND 66 22W ND 0.12 +/- 0.09 ND ND 3.29 0.70 ND 67 23B ND ND ND ND 1.03 +/-0.39 ND 23 68 23E ND 0.1 1 +/- 0.07 ND ND 3.33 +/- 0.56 ND 69 23W 0.56t +/-0.78 0.21 +/- 0.13 ND ND 3.47 +/-0.63 ND 70 24B ND ND 0.15 +/- 0.05 ND 1.16 +/-0.32 ND 23 71 24E ND 0.08 +/- 0.07 ND ND 3.26 +/- 0.76 ND T-25 Sample ID U-238 (63keV, 93 keV used when 63 not piesent) pCi/gZ Exposure Rate @ 1 m from trench bottom in jtR/hr ii*;iS; I

I

'%,.¸

I I

Table 9: S-18 to S-13 Sewer Drain Line Trench Final Soil Sample Results Radionuclide Concentrations (pCilg)

Background Not Subtracted,.30 nwin count (except as noted)

U-238 (163keV, 93 keV used when 63 not present)

Pcilg U-235 (1,44keV,186 keV used whien 144 not present)

I I

Cs-137 (662 keY)

Co-60.

((1170 1keV+1330 keV) /2)

IpCi/g I

Total Thoriumi Th-228(238 IceV), plu-s Th-232(9 11 keV)

IS t

I I

I pCi/g pCi/g DCifLn Other Isotopes 72 24W ND 0.17 +/- 0.10 ND ND 4.09 +/- 0.80 ND 73 25B ND ND ND ND 1.16 +/-0.32 ND 23 74 25E ND 0.10 +/- 0.06 ND ND 2.66 +/- 0.58 ND 75 25W ND 0.13 +/- 0.08 ND ND 3.75 +/- 0.72 ND 76 26B ND 0.04 +/- 0.03 ND ND 0.86 +/- 0.21 ND 23 77 26E 1.10 +/- 1.24 0.14 +/- 0.07 ND ND 3.35 +/- 0.57 ND 78 26W ND 0.12 +/- 0.08 ND ND 3.32 +/- 0.81 ND 79 27B ND ND 0.04 +/- 0.03 ND 1.15 +/- 0.30 ND 24 80 27E ND 0.16 +/- 0.08 ND ND 3.01 +/- 0.49 ND 81 27W 0.68 +/- 1.48 ND ND ND 3.69 +/- 0.64 ND 82 28B ND ND 0.06 +/- 0.05 ND 1.85 +/- 0.42 ND 22 0.97 +/- 0.94 0.19 +/- 0.10 ND ND 2.54 t 0.58 ND J __________

L _________

J j _________

II _____

T-26 Sample ID Exposure Rate Ca 1 m from trench bottom in ýMR/hr 83 28E n0la IQýtn,

Table 9: S-18 to S-13 Sewer Drain Line Trench Final Soil Sample Results Radioinuclide Concentrations (pCifg)

Background Not Subtracted, 30 ini. count (except as noted)

U-238 U-235 Cs-137

,Co'.60 Total Thoriuim

.Other Isotopes Exposure (63keV, 93

(:44keV,186 (662 keY)

(({1170 Thi228(238

.,Rate

@ I keV used keV used when keV+1330 keY., plu.s 2

from when 63 not 144 not

,keV)

/21 Tb-232(9i1 trench present) present),

keV)~

bottom SampleID in fLRohr pCi-g pCipCilgg pCig pCi Isotope 84 28W 0.99 +/-1.17 0.15 +/-0.11 ND ND 3.73 +/- 0.85 ND 85 29B ND ND ND ND 1.57 +/- 0.47 ND 21 86 29E ND 0.26 +/- 0.14 ND ND 3.56 +/- 0.73 ND 87 29W ND 0.06 +/- 0.10 ND ND 4.89 +/- 0.93 ND 88 30B ND ND ND ND 1.42 +/- 0.38 ND 19 89 30E 1.28 +/- 1.24 0.10 +/- 0.09 ND ND 3.34 +/- 0.62 ND 90 30W ND 0.12 +/-0.15 ND ND 3.83 +/- 0.75 ND 91 31B ND ND ND ND 0.96 +/- 0.09 ND 21 92 31E ND 0.21 +/-0.09.

ND ND 4.07 +/- 0.72 ND 93 31W ND ND ND ND 2.43 +/- 0.55 ND 94 32B ND ND ND ND 0.51 +/- 0.12 ND 23 95 32E ND 0.17 +/- 0.10 ND ND 3.80+/- 0.74 ND T-27

Table 9: S118 to S-13 Sewer Drain Line Trench Fi*ala Soil Sample Results I

I U-235 (l44keV,186 keV used when 144 not present)

A RadionuclideConcenltrations '-',"'g' B~ackground Not SubtracedQ 30 m. count (except as noted),

Cis-137 (66.2 keV)

((1170 keV+1330 keV) /21 I 'Total Thorium Th-228(238 keY), plus Th-232(9~1I kc V)

I I

t

.1 4

pCi/g PCilg

'pCi/g

O 96 32W ND 0.15. -0. 11 ND ND 3.37 +/- 0.74 ND 97 33B 0.54 +/- 0.59 0.07 +/- 0.05 ND ND 0.88 +/- 0.26 ND 24 98 33E 0.65 +/- 0.66 0.08 +/- 0.04 ND ND 1.54 +/- 0.30 ND 99 33W 1.67 +/- 1.53 ND ND ND 3.45 +/- 0.68 ND 100 34B ND 0.06 +/- 0.05 ND ND 1.49 +/- 0.47 ND 24 101 34E 1.08.+/- 1.21 0.10 +/- 0.06 ND ND 3.50 +/- 0.73 ND 102 34W ND 0.08 +/- 0.06 ND ND 2.52 +/- 0.56 ND 103 35B ND ND ND ND 1.32 +/- 0.40 ND 24 104 35E ND 0.23 +/- 0.10 ND ND 3.72 +/- 0.67 ND 105 35W ND 0.13 +/- 0.07 ND ND 3.57 +/- 0.70 ND 106 36B ND 0.04 +/- 0.04 ND ND 0.84 +/- 0.25 ND 25 107 36E 0.90 +/-1.20 0.10 +/-0.07 ND ND 3.96 +/- 0.66 ND Other Isotopes T-28 I

U-238 (63keV, 93 keV used when 63 not present)

Sample ID pCi/g Exposure Rate @ 1 im from trench bottom in ýLR/br pCifil iii nCi/g T*t*no:

9

Table 9: S-18 to S-13 Sewer Draiin Line Trench Final Soil Sample Results

~Radionuclide Concenstnated)ns________

U-238 Uý235 Cs-137 Co-60 Total Thoriumn Oth~er Isotopes Ex~posure (163keV, 93 (l44keV,1,86 (662 keY)

[(1170 1'h-228(238.

Rate @ I keY used keY used when keY+1330 keV), plus mn from when 63 not 144 not keY) /21 Th-232(911 trench present) present) keV) bottom Sample ID in I.LR/lhr pCilg pCi'g p C i pCi/g,,

pCilg pCi/g Isotope 108 36W ND ND ND ND 3.98 +/-0.77 ND 109 37B 0.79 t 0.78 ND 0.03 +/- 0.03 ND 0.97 +/- 0.28 ND 25 110 37E 0.78 +/-0.95 0.12 +/-0.08 ND ND 4.04 +/-0.67 ND III 37W ND 0.27+/-t0. 15 ND ND 4.13+/-t0.79 ND 112 38B ND ND ND ND 1.34 +/-0.42 ND 25 113 38E ND ND ND ND 4.00 +/-0.93 ND 114 38W ND ND ND ND 3.33 +/-0.68 ND 115 39B ND 0.03:1- 0.05 0.24 +/- 0.07 ND 1.16 +/- 0.33 ND 24 116 39E ND 0.15 +/-0.07 ND ND 4.24 +/-0.71 ND 117 39W ND 0.13 +/- 0.07 ND ND 2.21 +/- 0.53 ND 118 40B ND ND 0.13++/-0.06 ND 1.53 +/-0.41 ND 24 1940E 1.32 +/-1.26 0.17 +/- 0.07 ND ND 3.60 +/-0.71 ND T-29

Table 9: S-18 to S-13 Sewer Drain Line.Trench Final Soil Sample Results U-235 (l44keV,186 keY used iwen 144 not present)

Radionuclide Concentrations (pCilg)

Background Not Subtracted,, 30 mm.n coun~t (except as noted)

Cs-137 (662 keY)

(1(1170 keV+13?30, keV) /2)

Total Thorium Th-228(238 keV), plus Tbi-232(91 I keV)

I t

t I

I.

pCi/g pCilýg PCi/g tCi/g Other h-otopes DCi/ky 120 40W ND 0.23 t 0.13 ND ND 4.03 t 0.85 ND 121 41B ND ND ND ND 1.65 +/- 0.46 ND 24 122 41E 0.87 +/- 0.91 0.16 +/- 0.12 ND ND 3.43 +/- 0.63 ND 123 41W ND 0.17 +/- 0.11 ND ND 3.59 +/- 0.75 ND 124 42B 0.87 +/- 0.86 ND ND ND 1.36 +/- 0.32 ND 25 125 42E ND 0.05 +/- 0.08 0.01 +/- 0.04 ND 2.72 +/- 0.58 ND 126 42W ND 0.14+/- 0.11 ND ND 4.37 +/- 0.93 ND 127 43B ND 0.07 +/- 0.04 0.05 +/- 0.04 ND 1.82 +/- 0.39 ND 24 128 43E ND 0.17 +/- 0.09 ND ND 3.67 +/- 0.76 ND 129 43W ND 0.18 _+ 0.09 ND ND 3.93 +/- 0.84 ND 130 44B ND ND ND ND 1.24 +/- 0.35 ND 23 131 44E 0.93 +/-0.89 0.15 +/- 0.06 ND ND 3.27 +/- 0.71 ND T-30 Sample ID U-238 (63keV, 93 keV used when 63 not present) pCi/g Exposuire Rate @ 1 im from trench bottom in ýLihir Isotconi I

I M

I

Table 9; S-18 to S-13 Sewer Drain Line.Trench Final Soil Sample Results Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 min. count (except as noted)

U-238 U-235 Cs-137 Co'.60 Total Thorium Other Isotopes Exposure (63keV,93 (l44k-e',186 (662 keY)

((1170 <

Th228(238 Rate @ I

keV used keV used when keV+/-1330 keY), pls"nm from when 63 not 144 not keV) /2)'

Th-232(91 1

'trench present) present) keV) bottom Sample ID in It]R1hr pCijg pCilg pCilg

,pCi/g" pCilg

~

.pCilg Isotope 132 44E @ IM 1.43 +/-1.42 0.21+/- 0.11 ND ND 4.38 +/-0.88 ND 133 44E @2M ND 0.16 +/-0.10 ND ND 2.68 +/-0.77 ND 134 44W ND 0.12 +/-0.11 ND ND 3.58 +/-0.73 ND 135 44W @ IM ND ND ND ND 1.35 +/- 0.40 ND 136 44W @2M ND 0.11 +/-0.06 ND ND 1.98 +/-0.65 ND 137 45B ND 0.04 +/-0.05 ND ND 1.10 +/-0.26 ND

-24 138 45E 1.59 +/- 1.18 0.11 +/- 0.06 ND ND 3.52 +/- 0.58 ND 139 45E @ IM 0.94 +/- 1.14 0.14 +/- 0.10 ND ND 4.56 +/- 0.82 ND 140 45E @ 2M 0.70 +/-0.89 0.16 +/-0.07 ND ND 4.02 +/-0.66 ND 141 45W ND 0.12 t0,12 ND 0.04 +/-0.04 3.22 +/-0.62 ND 142 45W( 9IM ND 0.24+/- 0.15 ND ND 5.29 +/-0.82 ND

.43 45W @ 2M ND 0.21 +/- 0.12 ND ND 3.58 +/- 0.76 ND T-31

Table 9: S-18 to S.13 Sewer Drain Line Trench Final Soil Sample Results Radionuclide, Concentrations (pCi/g)

.Back~ground Not Sub~tracted, 30 min., count (except as noted)

II I

U-235 (144keV,186 keV used when 144 not present)

Cs-137 (662 keY)

Co-60

[(1170 keV+1330, keY) /2)

I t

1

'I pCi/g pCilg PCi/g' Total Thorium Th-228(238 k~eV), plus Th-232(91 1 lceV) pCvg Other Isotopes nCi/h Ttr~cfino 144 46B ND 0.08 +/- 0.05 ND ND 1.17 +/- 0.30 ND 26 145 46E 2.00 +/- 0.61 0.11 +/- 0.07 ND ND 3.73 +/- 0.63 ND 146 46E @ IM 1.08 +/- 0.95 0.17 +/- 0.07 0.16 +/- 0.06 ND 4.39 +/- 0.77 ND 147 46E @ 2M ND 0.16 +/- 0.09 0.26 +/- 0.08 ND 2.66 +/- 0.48 ND 148 46W ND ND ND ND 4.50 +/- 5.32 ND 149 46W @ 1M ND 0.19 +/- 0.11 ND ND 4.07 +/- 0.77 ND 150 46W @ 2M ND 0.17 +/- 0.13 0.28 +/- 0.09 ND 4.20 +/- 0.84 ND 151 47B ND 0.05 +/- 0.04 0.11 +/- 0.06 ND 1.20 +/- 0.33 ND 24 152 47E ND 0.10 +/- 0.07 0.22 +/- 0.06 ND 2.90 +/- 0.58 ND 153 47E @ IM 1.61 +/- 1.41 0.23 +/- 0.10 0.21 +/- 0.07 ND 3.98 +/- 0.67 ND 154 47E @ 2M ND 0.14 +/- 0.15 0.13 +/- 0.07 ND 5.18 +/- 0.93 ND 155 47W ND 0.05 +/- 0.05 0.12 +/- 0.05 ND 0.99 +/- 0.28 ND 156 47W @ IM 1.11 +/- 1.04 0.14 +/- 0.08 0.10 +/- 0.07 ND 4.19 +/- 0.82 ND T-32 I

I U-238 (163keV, 93 keV used when 63 not present)

Sample ID pCi/g Exposure Rate @ I m from trench bottom in l.LR~ir t :,:

% ?

.......... 5 :........

. % /

2 I

Table 9: S-18 to S-13 Sewer Drain Line Trench Firnal Soil Sample Results I

I1 U3-235 (144keV,186 keV used when 144 not present) pCi/g

'Radionuclide Concentrations (pCi/g)'

Background Not Subtracted, 30 muin. count (except as noted)

Cs-137 (662 lk&V)

Co-60 t(1170~

keV+133O' keY) /21 Total Thoriumi Tb-228(238 keY), plus keY)

Other Isotopes I

I 6

Pqijg PCi/g pCilg pCi/g Isotone 157 47W @ 2M ND 0.13 +/- 0.11 ND ND 4.73 +/- 0.96 ND 158 48B ND 0.24 +/- 0.13 0.81 +/- 0.14 0.20 +/- 0.10 3.06 +/- 0.63 ND 24 159 48E 1.07 +/- 0.93 0.18 +/- 0.08 0.41 +/- 0.09 0.18 +/- 0.08 3.72 +/- 0.69 ND 160 48E @ IM 1.91 +/- 1.77 0.21 +/- 0.09 ND ND 4.13 +/-0.66 ND 161 48E @ 2M ND 0.09 +/- 0.10 ND ND 4.24 +/- 0.77 ND 162 48W ND ND 0.22 +/- 0.06 ND 1.21 +/-0.35 ND 163 48W @ IM ND 0.12 +/- 0.07 ND ND 4.74 +/-0.83 ND 164 48W @ 2M ND 0.20 +/- 0.13 ND ND 4.05 +/- 0.81 ND 165 49B ND 0.07 +/- 0.04 0.07 +/- 0.04 ND 1.04 +/- 0.26 ND 27 166 49E ND 0.16 +/- 0.06 ND ND 3.99 +/- 0.66 ND 167 49E @ IM 1.61 +/- 1.39 0.19 +/- 0.07 ND ND 3.90 +/- 0.66 ND 168 49E @ 2M 1.59 +/- 1.34 0.16 +/- 0.10 ND ND 3.96 +/- 0.65 ND T-33 Sample ID U-238 (63keV, 93 keh used when 63 not present) pCilg Exposure Rate Ca I m from trench bottom in 4.R/hr Sv:

I I

y* * %,

f

)*<* =¸¸:¸_ 5 :

Table 9: S-18 to S.13 Sewer Drain Line Trench FinalSoil Sample Results Rad.ionuclide Concentrations (Pci*

.)

Background Not Subtracted, 30mmnin count (exccept as noted)

U-235 (l44,keV,186 keV used whien 144 not present)

I (662 keY)

I Co-60

( (1170 keV.4330

~Total Thorium Th-228(238, keV), plus Th-232(91 I Other Isotopes 1

1 1

1 V

pci/g pCilg PcijLg P C UP nGAk Isotone 169 49W ND ND ND ND 3.74 +/- 0.74 ND 170 49W @ IM ND 0.13 +/- 0.09 ND ND 4.34 +/- 0.79 ND 171 49W @ 2M 1.21 +/- 1.21 0.15 +/- 0.09 ND ND 4.52 +/- 0.75 ND 172 50B ND ND 0.01 +/- 0.05 ND 1.48 +/- 0.38 ND 26 173 50E ND 0.19 +/- 0.10 ND ND 4.44 +/-t 0.71 ND 174 50E @ IM 1.05 +/- 1.25 0.17_+/-0.07 ND ND 3.61 +/- 0.71 ND 175 50E @ 2M 1.16 +/- 1.27 0.20 +/- 0.10 ND ND 3.63 +/- 0.64 ND 176 50W ND 0.11 +/- 0.08 ND ND 3.26 +/- 0.65 ND 177 50W @ IM ND ND ND ND 4.78 +/- 0.84 ND 178 50W @ 2M ND 0.14 + 0.09 ND ND 4.53 +/- 0.74 ND 179 51B ND ND ND ND 1.54 t 0.44 ND 26 180 51E ND 0.13 +/- 0.10 ND ND 3.98 +/- 0.70 ND T-34 I

Sample ID U.238 (63keV, 93 keV used when 63 not present) pCilg Exposure Rate @ I mu from trench bottomn in pLRlhr

': U

/ :...............

.H.

I

Table 9: S-18 to S"13 Sewer Drain Line Trench Final Soil Sample Results Radionuclidew Concentrations C u i/9)t a d

Background Not Subtracted, 30 min. count (except as noted)

U-235 (l44k~eV,186 keY used wheni 144 not present)

Cs-137 (662 keY)

Co-60

('(1170 keV+1,330 keV) /2)

Total Thoriurn.

Th-228(238 keY), plus Th-232(911 keV)

Other Isotopes I

I' 9

4

'U pCi/g pci/gC pCilg pCilg Pci/g-Isotope 181 51E @ 1M 2.03 +1.65 0.18+/- 0.10 ND ND 3.79 +/- 0.62 ND 182 51E @ 2M 0.93 +/- 1.15 0.15 +/--0.08 ND ND 3.79 +/- 0.71 ND 183 51W ND ND ND ND 4.35 +/- 0.82 ND 184 51W @ IM ND 0.19 +/- 0.09 ND ND 4.72 +/- 0.77 ND 185 51W @ 2M ND 0.18+/- 0.11 ND ND 4.58 +/-0.80 ND 186 52B ND 0.02 +/- 0.08 0.02 +/- 0.05 ND 1.36 +/- 0.36 ND 26 187 52E 1.00 +/- 0.90 0.14+/- 0.07 ND ND 4.00 +/- 0.64 ND 188 52W ND 0.08 +/- 0.12 ND ND 4.45 +/- 0.97 ND 189 53B ND ND ND ND 1.20 +/- 0.34 ND 190 53E ND 0.18 I

0.08 ND ND 4,57 +/- 0.75 ND 191 53W ND ND ND ND 3.99 +/- 0.79 ND 192 54B ND 0.06 +/- 0.07 ND ND 1.33 +/- 0.33 ND 26 T-35

'U Sample ID "U-238 (63keV, 93 keV used when 63 not present) pCi/g Exposure Rate @ 1 mn fromn trenchi bottomr ill ýR/`hr S.........

.. L Z*

Table 9: S-18 to S-13 Sewer Drain Line Trench Final SoI Sample Results Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 min. count (ex.cept as noted)

I I

I J

U-235 (l44keV,186 keV used when 144 not present)

Cs-137 (662 keY)

Co-602

( (1170 keV+1330, keV) /21 I

f t

1.

pCilg pciIg vcikg Total Thorium Th-228(238 keY), plus Thi-232(91 1 keV) nCilP.

Other Isotopes nC'ili TQtýr r,

-I 193 54E 1.36 +/- 1.31 0.15 + 0.09 ND ND 3.69 +/- 0.65 ND 194 54W ND 0.07 +/- 0.07 ND ND 4.04 +/- 0.69 ND 195 55B ND ND ND ND 1.35:+/-10.38 ND 26 196 55E 1.96 +/- 1.50 0.14 +/- 0.08 ND ND 3.38 +/- 0.55 ND 197 55W ND ND ND ND 4.88 +/- 0.87 ND 198 56B ND ND ND ND 1.76 +/- 0.37 ND 27 199 56E ND 0.17 +/- 0.14 ND ND 3.94 +/- 0.73 ND 200 56W 0.77 +/- 0.81 0.14 +/- 0.09 ND ND 3.54 t 0.65 ND 201 57B ND ND ND ND 1.92 +/- 0.42 ND 26 202 57E ND 0.22 +/- 0.10 ND ND 5.04 +/- 0.88 ND 203 57W ND ND ND ND 3.91 +/- 0.93 ND 204 58B ND ND ND ND 1.03 +/- 0.29 ND 26 T-36 U-238 (63keV, 93.

keV used when 63 not present)

Sample ID pCi/g Exposure Rate @ I mn from tren~ch bottomn in jiRllir i

S.

. H __ H -.

I

_________Table 9: S-18 to S-13 Sewer Draiin Line Trench Final Soil Sample Results Radionuclide Concentraitions (pCi/g)

___________Backg round Not Subtracted, 30 inin. count (except as noted)

U-238 U-235 Cs4137 Co-60 Total Thorium Other Isotopes Exposure (63keV, 93 (144keV, 86 (662 keV)

~

f{(1170 Th-228(238 Rate @ I

keV used keY used wien keV+1,330 keV), plus mn from when 63 not 144 not keV) /2)

Th.232(911 trenchi present) present) keY)

,bottom Sample ID in ý.LR/hr PCig pCi/g pCilg

.pCilgC' pCi/g pCilg Isotope 205 58E 0.63 t 0.73 0.21 t 0.09 ND ND 3.90 +/- 0.65 ND 206 58W 1.66 +/- 1.21 0.18 +/-0.08 ND ND 3.56 +/- 0.59 ND 207 59B ND 0.09 +/- 0.05 ND ND 0.98 +/- 0.31 ND

-27 208 59E ND 0.22 +/-0.08 ND ND 3.36 +/-0.69 ND 209 59W ND ND ND ND 3.91 +/-0.85 ND 210 60B ND ND ND ND 0.95 +/-0.31 ND 27 211 60E 0.99+/-t 1.09 0.14+/-t0.11 ND ND 3.53 +/-0.76 ND 212 60W ND

0. 16 t+/-0.07 ND ND 2.61 +/- 0.57 ND 213 61B ND ND ND ND 0.32 +/-0.12 ND 25 214 61E ND 0.12 +/-0.11 ND ND 3.52 +/-0.75 ND 215 61 W ND ND ND ND 3.15 +/-0.65 ND 216 62B ND ND ND ND 1.38 +/-0.34 ND 27 T-37

Table 9: S-18 to S13 Sewer Drain Line Trr*nch Final Soil Sample Results Radionuclide Concentrations (pCiIg)

Ba~ckground Not Subtracted, 30 m. count (except as noted)_

U-238 U-235 Cs-137 Co-60 Total Thojrium Other otopes Exposure (63keV,"93 (l44keV186 (662 keV)

((1179

T"-228(

8 Rate @ I keV used keV used when keV+1330 keY), plus m from when 63 not

.144 not keV)12)

Th232(911 trench present) present) keV) bottom Sample ID in pR/~hr PCi/g pGi/g pCilg pCil-g pCilg p)Ci/g Isotope 217 62E ND 0.16 +/-0.10 ND ND 4.20 +/-0.76 ND 218 62W ND 0.14 +/-0.09 0.04 +/-0.06 ND 3.05 t0.72 ND 219 63B ND 0.06 +/-0.05 0.30 +/-0.06 ND 1.66+/-t0.35 ND 27 220 63E ND 0.13 +/-0.08 ND ND 4.78 +/-0.80 ND 221 63W ND ND ND ND 4.23 +/- 0.75 ND 222 64B ND 0.08+/-t0.06 0.09 t+/-0.04 ND 1.71 +/- 0.43 ND

-28 223 64E ND 0.13 +/-0.06 ND ND 3.47+/-1-0.71 ND 224 64W ND ND ND ND 4.06 +/- 0.66 ND 225 65B ND 0.10 +/-0.04 ND ND 1.97 +/-0.38 ND 27 226 65E ND 0.08 +/- 0.08 ND ND 3.05 +/- 0.65 ND 227 65W 0.38 +/- 0.89 0.13 +/- 0.11 ND NDl 4.09 +/- 0.72 ND 228 66B ND ND ND ND 1.59 +/- 0.44 ND 29 T-38

Table 9: S-18 to S-13 Sewer Drain Line Trench Final Soil Sample Results U-235 (144keV,186 keV used when 144 not present)

.Radionuclide Concentrations (Pci/g)

Backgrouind Not Subtracted, 30 mmn. count (except as noted)

Cs-137 (662, keV)

Co-60

((1170 keV+/-133O.

keV) /21 Total Thorium Th-228(1238 keV), plus Th-232(91 1 keV)

Other Isotopes t

I A

I U

PCi/g p C il.,

pj/g ncif2 nCi7-Thctrin

229 66E 1.53 +/- 1.35 0.12 +/-0.07 ND ND 3.53 +/- 0.58 ND 230 66W ND 0.11 + 0.10 ND ND 4.37 +/- 0.94 ND 231 67B ND 0.11 +/-0.05 0.04 +/- 0.06 ND 2.05 +/- 0.46 ND 28 232 67E ND 0.17 +/- 0.10 ND ND 3.61 +/- 0.58 ND 233 67W ND 0.19 +/-0.16 ND ND 4.02 +/- 0.75 ND 234 68B ND ND ND ND 3.91 t 0.72 ND 28 235 68E 1.29 +/- 1.25

0. 15 + 0.07 ND ND 4.11 +/- 0.78 ND 236 68W ND ND ND ND 3.92 +/- 0.78 ND 237 69B 0.56 +/- 0.44 0.08 +/- 0.05 0.05 +/- 0.04 ND 1.66 +/- 0.33 ND 28 238 69E ND 0.13 +/- 0.07 ND ND 2.75 +/- 0.48 ND 239 69W ND 0,16:+/- 0.13 ND ND 4.31 +/- 0.86 ND 240 70B 0.48 +/- 0.47 ND 0.03 +/- 0.03 ND 1.61 +/- 0.32 ND 28 T-39 U-238 (63keV, 93 keV used when 63 not present)

Sample ID pCi/g Exposure Rate @ 1 m from trench bottom in j.LR/hr "I

I.

' /

" L a

I

Table 9: S$18 to S.K13 Sewer Drain Line Trench FJinal Soil Sample Results Radionuclide3Concentrations (pCieg)

Background Not Subtracted, 30 rnin. count (except as noted) 1U-235 (144keV,186 keV used when 144 not present)

Cs.137 (662 keV)

I I Co-60, t{(1170 keV+/-1330 keY) /2}

Total Thorium Tb-228(238

~keV), plus Th4232(91 1 keY)

T I

t 4

pCi/g pCiig pCi/p pCilg I

1

Other Isotopes oCiko Thotone 241 70E ND 0.17 +/- 0.09 ND ND 3.26 +/- 0.71 ND 242 70W 1.68 +/- 1.73 0.16 +/- 0.08 ND ND 4.90 +/- 0.92 ND 243 71B ND 0.08 +/-0.07 ND ND 1.44 +/- 0.44 ND 28 244 71E 0.86 +/- 1.02 0.20 +/- 0.13 ND ND 4.07 +/- 0.84 ND 245 71W ND ND ND ND 3.30 +/- 0.59 ND 246 72B ND 0.11 +/- 0.06 0.11 +/- 0.05 ND 2.01 +/- 0.42 ND 28 247 72E 0.80 +/- 1.02 0.12 +/- 0.11 ND ND 4.02 +/- 0.74 ND 248 72W ND 0.22 +/- 0.10 ND ND 4.59:+/- 0.91 ND 249 73B ND 0.12 +/- 0.05 0.07 +/- 0.05 ND 2.01 +/- 0.42 ND 28 250 73E 0.98 +/- 1.13 0.17 +/-0.11 ND ND 3.75 +/- 0.71 ND 251 73W ND 0.14 +/- 0.09 ND ND 4.02 +/- 0.88 ND 252 74B ND ND ND ND 1.44 +/- 0.12 ND 28 T-40 I

I I

U-238 (63keV, 93 keV used when 63 not present)

Sample ID pCijg Exposure Rate C@

1 n from trench bottom in jýtR/hr S...

, - 5 * * :* '::*................

H ;*, *¸ =:*

I I

Table 9.- S-18 to S-13 Sewer Drain Lin~e Trench Final Soil Sample Results Radionuclide Concentrations (pCilg)

Back-ground Not Subtracted, 30 min., count (except as noted)

U-235 (l44keV,186 keV used iwhen 144 not present) pCi/g I.' Cs-137' (662, keY) a

~<Co-.60

((1170 keV+1330 keY) /21 Total Thorium Th-228(238 keV) plus~

Th-232(91 1 keY),

t I

pCilg-PCilg nC112 Other Isotopes nCiI'

Tntnn

253 74E ND 0.21 +/- 0.09 ND ND 4.28 +/- 0.86 ND 254 74W ND 0.17 +/- 0.11 ND ND 4.25 +/- 0.92 ND 255 75B ND ND ND ND 1.58 +/- 0.43 ND 28 256 75E 2.09 +/- 1.55 0.21 +/- 0.09 ND ND 3.76 +/- 0.64 ND 257 75W ND 0.10 +/- 0.10 ND ND 4.71 +/- 0.81 ND 258 76B ND 0.07 +/- 0.05 ND ND 1.51 +/- 0.28 ND 28 259 76E 0.58 +/- 0.93 0.14 +/- 0.07 ND ND 3.08 +/- 0.60 ND 260 76W ND 0.02 +/- 0.12 ND ND 3.70 +/- 0.81 ND 261 77B ND 0.15 +/- 0.08 ND ND 2.75 +/- 0.49 ND 27 262 77E ND 0.21 +/- 0.08 ND ND 3.84 +/- 0.71 ND 263 77W ND 0.17 +/- 0.09 ND ND 3.57 +/- 0.67 ND 264 78B ND 0.07 +/- 0.05 ND ND 2.12 +/- 0.43 ND 27 T-41 1

1.

Ir U-238 (63keV, 93 "keV used when 63 not present)

Sample ID pCilg Exposure Rate @ I m from trench bottom in j.LR/hr I

I!

Table 9:; S-18 to S.13 Sewer Drain Line Trench Final Soil Sample Results Y

r U-235 (l44keV,186 keV used when 144 not present)

Cs4137 (662 keV)

Co-60 t (1170 keV+1330 lceV) /21 Total Thorium~

Th-228(238 keY), plus Th-232(91 1 keY) 1

'3 3'

t 4

PCilg pCilg nCi1

nCi/v nCiI

Other Isotopes Tzntnn.

Exposure Rate @ 1 m from trench bottom in Is/hlr

-ci/,g 265 78E 0.82 +/- 1.02 0.18 +/-0.08 ND ND 3.78 +/- 0.72 ND 266 78W ND 0.10 +0.11 ND ND 4.54 +/- 0.99 ND 267 79B ND ND 0.25 +/- 0.06 ND 2.01 +/- 0.40 ND 27 268 79E ND 0.18 +/- 0.10 ND ND 3.74 +/- 0.67 ND 269 79W ND 0.13 + 0.09 ND ND 3.92 +/- 0.86 ND 270 80B ND ND 0.25 +/- 0.09 ND 2.12 +/- 0.60 ND 27 271 80E 0.69 +/- 0.98 0.12 +/- 0.07 ND ND 3.50 +/- 0.70 ND 272 80W ND 0.16 +/- 0.10 ND ND 4.65 +/- 0.86 ND 273 81B ND 0.14 +/- 0.08 ND ND 2.41 +/- 0.52 ND 27 274 81E 1.62 +/- 1.71 0.23 +/- 0.12 ND ND 4.32 +/- 0.79 ND 275 81W ND 0.16 +/- 0.08 ND ND 3.79 +/- 0.72 ND 276 82B 0.36 +/- 0.69 0.10 +/- 0.05 ND ND 2.19 +/- 1.96 ND 27 T-42 U-238 (63keV, 93 keV used when 63 not present)

Radionuclide Concentrations I(pCi/g)

Background Not Subtracted, 30 min, count (except as noted)

Sample ID pCi/g I

T*¸¸ I

I

Table 9: S-18 to S-13 Sewer Drain Line Trench Final Soil Sample Results Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 mmi.

count (except as noted)

U-238 U-235 (2s437 Co.-60 Total Thorium Other Isotopes Exposure (31(eV, 93 (144keV,186 (662 keV) f{(1170 Th-228(238 Rate @ I

keV used keV used when keV+1330 keV), plus mn from when 63 not 144 not 7keY) /21.

Th.-23.2(911 trench present) present) keV) bottom Sample ID

.in e..R/hr pCi/g pCig pCi/g pCi/g pCi/g pCi/*.

Isotope 277 82E 1.84 t 1.44 0.15 +/- 0.08 ND ND 3.56 +/- 0.58 ND 278 82W ND 0.17 +/- 0.12 ND ND 5.12 +/- 0.85 ND 279 83B ND 0.09 +/- 0.09 ND ND 2.00 +/- 0.47 ND 27 280 83E ND 0.14 +/- 0.08 ND ND 3.73 +/- 0.85 ND 281 83W ND 0.19:+/- 0.13 ND ND 4.50 +/- 0.86 ND 282 84B ND 0.15 +/- 0.09 ND ND 2.20 +/- 0.52 ND 27 283 84E ND 0.13 +/- 0.13 ND ND 3.91 +/- 0.72 ND 284 84W ND 0,07 +/- 0.10 ND ND 4.39 +/- 0.76 ND 285 85B ND ND ND ND 1.60 +/- 0.46 ND 25 286 85E 1.56 +/- 1.23 0.16 +/- 0.09 ND ND 4.02 +/- 0.66 ND 287 85W ND ND ND ND 4.21.+/- 0.84 ND 288 86B ND 0.04 +/- 0.05 ND ND 1.02 +/- 0.26 ND 24 T-43

Table 9: S-18 to S-13 Sewer Drain LineTrench FinalSoil Sample Results Radionuclide Concentrations (pCilg)

Background Not Subtracted, 30 mn.n count (except as~ noted)

U-.235 (l4,4keV, 186 keV used when 144 not present)

Cs-137 (662 keV)

Co-60~

{(0170 keV+1330 keV) /21 Total Thorium Th-228(238 keV), plus Th-232(91 1 jkeV),

Other Isotopes I

r

'I I.

I pCilg pCi/g oCiIg n)CiLn nfli/h l

289 86E ND ND ND ND 1.51 +/- 0.37 ND 290 86W (2 hr) 1.82 +/- 1.15 0.18 +/- 0.05 ND ND 4.37 +/- 0.58 ND 291 87B ND ND ND ND 1.68 +/- 0.40 ND 24 292 87E 1.42 +/- 1.13 0.17 +/- 0.08 ND ND 3.64 +/- 0.79 ND 293 87W ND 0.16 +/- 0.10 ND ND 5.35:+/- 0.92 ND 294 88B ND 0.07 +/- 0.05 ND ND 2.23 +/- 0.49 ND 26 295 88E ND 0.13 +/- 0.10 ND ND 2.32 +/- 0.49 ND 296 88W ND ND ND ND 0.37 0.12 ND 297 69 post Decon 0.41 +/- 0.64 0.11 +/- 0.08 0.52 +/- 0.08 ND 2.16 +/-0.46 ND 298 EAT-1(1 hr) 3.17 +/- 1.82 0.41 +/- 0.07 ND ND 2.73 +/-0.42 ND 299 EAT-2(10 hr) 2.59 +/- 1.40 0.22 +/- 0.09 0.03 +/- 0.01 ND 3.71 +/- 0.40 ND 300 EAT-3 2.93 +/- 1.78 0.41 +/- 0.08 ND ND 3.12 +/- 0.56 ND 301 Vault Area Root ND ND 1.09 +/- 0.19 ND 0.10 +/- 0.13 ND T-44 U-238 (63keV, 93 key used when 63 not present)

Sample ID pci/g Exposure Rate @o)

I m from trench bottom in [LR/hr

!i:

I j*

jr*:*<;5*.:>

¢ *................................

Table 9: S-18 to S-13 Sewer Drain Line Trench Final Soil Saimple Results I

I U-235 (144keV,186 keV used when 144 not present)

Radionuclide Concentrations (pCilg)

B1ackgrousnd Not S'ubtrac'ted, 30 min. count (except as noted)

Cs-I$7 (662 keY)

Co.

keV+

keV) 17.0 1330

/2)

Total Thoriu~m Th-2~28(238 k-eV), plus Th.-232(91 I SkeY)

Other Isotopes T

I.

V I

I pCi/g IP~iG/

PCiIg vCik nCiI

Thctcine.

Exposure Rate @a I m from trench bottom in J.LR/hr

-~i/g

_-ila-Isot me 302 Vault Area Root-2 ND ND 0.91 +/- 0.15 ND 0.26 +/- 0.20 ND 303 Vault Area leaves ND ND ND ND 0.22 +/- 0.23 ND 304 Vault Area Bush ND ND ND ND 0.09 +/- 0.09 ND 305 Fence area leaves ND ND ND ND 0.10 +/- 0.10 ND 306 Fence Area Roots ND ND ND ND 0.10 +/- 0.10 ND 307 BKG (Fill Soil)

ND 0.11 +/- 0.07 ND ND 1.80 +/- 0.45 ND Shaded areas indicate filled in trench.

ND = Not detected, <0.1 pCi/g Cs-137, <0.1 pCi/g Co-60, <3.0 pCi/g U-238, <0.3 pCi/g U-235 Exposure rate @ 1 m from trench bottom in [IR/hr were taken every 2 m. Readings ranged from 18 - 28 [tR/hr.

Sample ID: B=Bottom E= East Wall W=West Wall T-45 I

U-238 (63keV, 93 keV used when 63 not present)

Sample ID pCilg Notes:

1.

2.

3.

4.

I I

SH r:r * :L* _*%,*

= :: * *

-*p R* *> :>* :*y::? (?*r *

? 5,..

)5:* ; : *<*

Table 10: Final Soil Sample Results from the S-18 to S-15 Trench and Building 25 to S-15 Trench Radionuclide Concentrations (pCi/g)

Background Not Subtracted, 30 minute count (except as noted)

U-238 U-235 Cs-137 Co-60 Total Thorium Other Isotopes (63 keV, 93 (144 keV,186 (662 keV) f{(1170 Th-228(238 Sample ID keV used keV used when keV+1330 keV), plus when 63 not 144 not keV) /2}

Th-232(911 present) present) keV) pCi/g pCi/g pCilg pCi/g pCi/g pCi/g Isotope 1

1 1.47+/- 1.35 0.32 +/- 0.09 ND ND 3.52 +/- 0.73 ND 2

2 (2hr) 2.28 +/- 1.34 0.38 +/- 0.08 ND ND 3.62 +/- 0.48 ND 3

3 1.62 +/- 1.55 0.33 +/- 0.11 ND ND 3.35 +/- 0.67 ND 4

4 2.38 +/- 2.03 0.25 +/- 0.1 ND ND 3.17 +/- 0.67 ND 5

5 1.26 +/- 1.32 0.21 +/- 0.08 ND ND 2.53 +/- 0.54 ND 6

6 2.41 +/- 1.60 0.32 +/- 0.07 ND ND 3.07 +/- 0.63 ND 7

7 1.27 +/- 0.10 0.29 +/- 0.09 ND 0.02 +/- 0.04 2.67 +/- 0.55 ND 8

8 ND 0.12 +/- 0.08 0.21 +/- 0.07 ND 3.35 +/- 0.71 ND 9

9 (2hr) 5.36 +/-2.87 0.32 +/- 0.31 ND ND 4.03 +/- 1.71 ND 10 10 2.78 +/-2.05 0.18 +/- 0.09 ND ND 2.94 +/- 0.62 ND Notes:

1.

Samples 1 through 8 are from the S-18 to S-15 Trench, samples 9 and 10 are from the Building 25 to S-15 Trench.

2.

ND =Not detected, <0.1 pCi/g Cs-137, <0.1 pCi/g Co-60, <3.0 pCi/g U-238, <0.3 pCi/g U-235 T-46

Figure 1: Main Site and Sorrento Valley Site Building Numbers Names Building 1 Administration N

Building 2 Science Laboratories A, 8, C.

Building 7 Cafeteria E

Building 9 Experimental Building Building 10 Maintenance Building 0

y Building 13 Technical Office Building S

Building 14 Technical Office East M>

Building 15 Technical Office East Building 19 Swimming Poul Building l

tf Building 21 TRIGA Building Building 22 TRIGA Fuel Lab Building9r 39 Building 23 Former Hol Cell Building 25 Waste Yard Building I

Building 27 Experimental Area Building 27-7 Experimenlal Area I

I INDUSTR.

Building 29 Experimental Area Building 29-2 Emergency Vehicle Storage Building F

I Building 30 LINAC Complex Building 31 TRIGA Storage Building Building 31-1 Neutron Radiography Building Building 31-2 ECF Critical Building 1

Building 31-3 Storage Building Building 33 Fusion Building DUNHILL Building 33-1Fusion Lab Building D

S Building 33-5 Fusion Building Annex 5 4-2 4-3 Building 34 Fusion Doublet Ill Building Building 34-1 Fusion Daublet Ill Capacitor Building 3

Building 34-2 Fusion Donublet Ill Lab Building 3

Building 34-3 Fusion Doublet III Storage Building 4-1 Building 35 Tesl Tower Building Building 35-1 Facilities (Shipping & Receiving) Building Building 36 Blower Assembly Building 4

A Building 37 Sorrento Valley Building Building 39 Sorrenlo Valley Building Building 39-1 Storage Building LOT 32

" SORRENTO VALLEY Building 41 Raw Stock Facility 3

Building 42 NDT Facility Building 45 Helium Circulalor Test Facility SITE Building 63 3550 Dunhill St.

.?

Building 64 11030 Roselle SI.

/

Building 65 11040 Roselle SI.

C ONTROLLED OPEN SPACE Building 66 3520 Dunhill St.

/

ACCESS Building 66 3510 Dunhill St.

/

SPEB MAIN SITE

/ 31-2 ISrPA

-CEune>Yr LOTS 31-3

-22

-23 21 S27 & 27-1 OR)N Traile IINDUSTRY 25a a

00 0

2 U

D L

3 LOTS SPROPERTY LINE 0

250 500 750 1000

(

SCALE IN FEET

Figure 2: Torrey Pines (Main) Site Sewer Lines El Pump Station S-15 is contaminated Previous

/ "<

)*

2,0 0',

HOT.........

Contaminatedpup1 Tree Location S\\

iSta tio* n Uncovered Vault 17

\\t\\

i

.2../,i iInstalled S*

~New LineIII s \\,i Buildingn92 V*//,/

B-7*

~

Bilin 9 N N

/

'N"

//

Property Boundary 02/01/02 44<2

5. 12.

Figure 3B: S-18 to S-13 Trench Measurements 722' Total Length4 N

A W

E S

Unknown Vault Building 25

Page 1 of 1 file://A:\\4Disassembly.j pg 02/02/2002

Page 1 of I file://A:\\5Contaminatedtree.jpg020/02 02/02/2002

Page 1 of 1 file://A:\\6TheRoot.jpg

-A 02/02/2002

Page 1 of I file://A:\\7UncoveredVault.j pg 02/02/2002

Page 1 of 1 file://A:\\8EcuTree.jpg 02/02/2002

11/20/2001 Figure 9: S-18 to S-15 Surface Soil Samples and Direct Radiation Measurements s

17

/

nn =Denotes Contact Readin*

22 21 21 Bldg 31-1 nn = Denotes One Meter Reading n

= Denotes Soil Sample Location 25

Figure 10: S-18 to S-13 Surface Soil Samples and Pipe Sludge Sample Locations yVR-15 #17 SludgeF @35ý9 s

iVR-I5 #16 Sl 49 W

N-E 3 11/20/2001 - 12/30/2001 VR-15 #8 Sludge ý 165'

-1VR-15 #6 Sludge @ 115' Bldg 31-2 No Drain line Electrical Trench Only =

Figure 11 : S-18 to S-13 Post Drain Line Removal Soil Samples Locatioi I VR-15 #18 Sludge @379' s

4 1-l 71 W+

E VR-I5 #16 Sludge@334' 4026 N

VR-15 #15 Sludge @ 300' 25 S V-I R

i#12 Sl'Unnaed Vault@

IVR-15 13 Sludge @ 274 21 g VR-1 5 95 Sludge VR-15 #11 Sludgel @

240' -..

N N N

-15 #10 Sludge @215 33 Fence V-13 Li.

-15 #9 Sludge 32R lot taken not ugh debris for 31 VR-15 #27 Sludge @ 604' sampling 90' 9 30 1-VR-15

3 Sludge 29 18 VR-VRd@25 R-VR-5#23 Sludge-@504

/31 71 44 1Bldg I

131-2 11/20/2001 - 12/30/2001

Figure 12: S-15 to S-13 Final Survey Soil Sample Locations 0 = Denotes Soil Sample Taken On Bottom of Trench

= Denotes Soil Sample Taken at 5-8" from Bottom of Trench On Wall 0 = Denotes Soil Sample Taken at One Meter from Bottom of Trench On Wall

@ = Denotes Soil Sample Taken at Two Meters from Bottom of Trench On Wall

= Denotes Suspect Affected Area M = Denotes Area Not Surveyed Bottom West S-15 East Side Side 8

0 0

8 i

8 I,

4 Area Not Surveyed 4

0 8

8 8

0 8

8 2

3 4

5 6

7 8

9 10 Fence 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 West East Side Bottom Side 0

" 0 0

0 0

8 8

32 33 34 35 36 37 38 39 40 41 42 43 West East Side Bottom Side 0

63 64 G

65 0

66 8

67 G

68 8

69 8

70 8?

71

- 0 72 0

73 0*

74 8

75 76 0

77 78

.80 8

81

.82 083 84 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 01/26/2002 85 86 87 88 0

00 0

)9 a

l 0 0

0 j

0

0

@ 1--

0 0

90

@ ©0 0 0

©0@a

ý0

Figure 1 21 jiR/hr 20 j.R/hr 19 jiR/hr 20 jlR/hr 20 jiR/hr 19 j+/-R/hr 18 jiR/hr 19 jIR/hr 19 jiR/hr 19 jiR/hr 18 jiR/hr 18 ItR/hr 19 2MRhr Area Not

[

Surveyed 19 pR/hr 21 pR/hr 24 piR/hr 23 ILR/hr 22 -iR/hr 23 jiR/hr 23 IiR/hr 23 giR/hr 23 g*R/hr 24 gtR/hr 22 VtR/hr 21 ptR/hr 19 gtR/hr 21 ptR/hr 14 15 16 17 18 20 21 22 23 24 26 27 28 29 30 31 24 g.R/hr 0

26 gR/hr 9

24 siR/hr 24 gtR/hr 27 i[tR/hr *

(

26 VtR/hr 26 ILtR/hr 9

26 iR/hr 25 1LR/hr 26 gR/hr 26 ýtR/hr 27 fiR/hr 26,iR/hr 26,iR/hr 27 jtR/hr 27 ILR/hr 25 gR/hr 27 RR/hr 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 2 81LR/hr 27 j.R/hr 2 7 gR/hr 27 giR/hr 27 [t R/h r 27 1iR/hr 27 IR/hr 27 jiR/hr 27 pR/hr 25i+/-R/hr 24 1gR/hr 24 tIR/hr 26 j+/-R/hr 76 77 78 79 80 81 82 83 84 85 86 87 88 3: S-15 to S-13 Final Survey Fixed Radiation Measurements and Results 01/26/2002 Sodium Iodide One Meter Readings 0

=Denotes Soil Sample Taken On Bottom of Trench

-=Denotes Soil Sample Taken at 5-8" from Bottom of Trench On Wall 0 -Denotes Soil Sample Taken at One Meter from Bottom of Trench On Wall

=Denotes Soil Sample Taken at Two Meters from Bottom of Trench On Wall 0 =Denotes Suspect Affected Area

= Denotes Area Not Surveyed Bottom West S-15 East West East West East Side Side Side Bottom Side Side Bottom Side 1

23 iR/hr 32 2 7 1IR/hr 63 2 24 jiR/hr 3328 p Rh r64 3

24 R/hr 34 2 7 jpR/hr 65 4

24 ILR/hr 3

9I

/r6 5

25 LIR/hr 36 28 gR~hr 067 "6

25 [LRhr 37 2 8 1pR/hr 68 7

25 gR/hr 38 28 i R/hr 69 8

24 ILR/hr 39 28 A R/hr 70 9

24 gR/hr (040 28 gR/hr 71 (910 24 t1R/hr Q41 2 8jiR/hr 72 Fence 25 pR/hr 42 28 p R/hr 73 12 24pRhr

/ 43 28jjR/hr 74 13 23 pR/hr 0

9 0

44 28 gR/hr 75 O0 0 O0 0 00 00 0

90 0 D a 0

0 Q

-0

Figure 14: S-15 to S-13 Final Survey Direct Radiation Scan Survey Locations and Results

=Denotes Soil Sample Taken On Bottom of Trench 12/2312001 - 01109/2002

=Denotes Soil Sample Taken at 5-8" from Bottom of Trench On Wall

=Denotes Soil Sample Taken at One Meter from Bottom of Trench On Wall

=Denotes Soil Sample Taken at Two Meters from Bottom of Trench On Wall q =Denotes Suspect Affected Area N =Denotes Surface Scan of filled Trench Area Bottom West Side East Side 32 S-15 East Side S

S

-- 0 S S

S+

S!

-S+

S_

Se 0

S.

S

+...

18 - 37 [gR/hr 18 - 21 g*/hr 18 - 22 gLR/hr 18 - 24 g*/hr 18 - 24 gR/hr 18 - 27 gLR/hr 18 - 22 gR/hr 15 - 20 g*/hr 18 - 21 gR/hr 16 - 21 tgR/hr 16 - 18.Ri/hr 16 - 18 p1R/hr 18 - 22 gR/hr 15 - 17 gR/hr 15 - 17 gR/hr 15 - 17 RB/hr 16 - 18 g.R/hr 16 - 18

/R]hr 20 - 22 1.R/hr 24 - 26 g.R/hr 24 - 26 gR/hr 20 - 25 gLR/hr 20 - 25 gR/hr 20 - 25 IgR/hr 20 - 25 g*/hr 20 - 25 gR/hr 20 - 25 gR/hr 20 - 25 g*/hr 19 - 25 gR/hr 15 - 20 gR/hr 20 - 25 gR/hr 2

3

ý4 5

6 7

9 10 11 12 13 14 18 19 20 21 22 23 24 "25 26

---27 28 29 30 31 L

1 West Side Bottom 20 - 25 gR/hr 20 -25 gR/hr 20 -25 i.R/hr 20-25 gR/hr 20-25gR/hr 20 - 2SpR/hr0 20-25p.R/hr 20-25 gR/hr 0

20-25g R/hr 0

20-25 gR/hr 20-25jiR/hr 192-255gRrhr 0

S 22--526h

,Rhr 23F-27 2Rhr

0 22-2 27/hr 22-2671R/hr 24 - 26 p1R/hr 0

24-27gR/hr X 0

24-27 jiR/hr 5

0 24 -27 gRhr 22 -26gpR/hr 247-/27hgR/hr 24 27 Rh Rhr 24 - 27 iR/hr 24 - 26 R/hr 0

24 - 26 gWR/hr 23-27gR/hr 0

24-27-5R/hr 22-26 gR/hr 22 - 27 gR/hr 0

24 - 28 gR/hr 25 - 28 pR/hr 25 - 28 tLR/hr 25 - 28 gll/hr 25 - 28 gR/hr 23 - 25 gLR/hr 25 - 28 gLR/hr 24 - 26 gLR/hr 25 - 28 gLR/hr 25 - 28 giR/hr 25 - 30 ILR/hr 23 - 28 pR/hr 25 - 30 gR/hr 23 - 26 g/hr 25 - 30 FLR/hr 23 - 27 gR/hr 25 - 30 pR/hr 23 - 27 g*/hr 25 - 30 gR/hr 25 - 30 gR/hr 23 - 27 gR/hr 24 - 27 g.R/hr 33

".34 35 36 37 38 39 40 41 42 43

-Xe 52

.53 54 55 56 57 158 59

.**60 62 West East Side Bottom Side 63

e 64 65 66

e 67 S

i 68 69 70 e

71 72

{*

73 74 75 76 77 78 79 80 81 82 83 84 0*._

z S

S-I3 0

S 0

S S

0 0

0 S

85 86 87 88 22 - 27 IgR/hr 22 - 27 pR/hr 22 - 27 IgR/hr 22 - 27 gtR/hr 44 45 46 47 48 49 50 51

Figure 15: S-18 to S-15 and Building 25 to S-15 Final Soil Sample Locations Nfn: = Denotes Final Soil Sample Location N

1 A

S-18 Building 25 25' i

2 3

4 r2 5

6 7

3>

8

/

9 I

10 1(4' 11 12 13 14 15 0

16 (1

17 18 iýC7 19 9

20 S-15 02/04/2002 130'

Figure 16: S-18 to S-15 and Building 25 to S-15 Final Survey Direct Radiation Scan Survey Locations and Results 02/04/2002 N

W l*E S-18 S

1 23-25[ R/hr 2

22-25[tR/hr 3

22 - 25 ý R/hr 4

21 - 25 1 R/hr 5

20 - 25 ýt R/hr 6

21 - 25 t R/hr 7

22 -25i R/hr 8

21 - 25. R/hr 9

22 - 25tL R/hr 10 22 - 25 1 R/hr 21-28plR/hr I12-7-~h 130' S11 22 - 27 !1 "/r 10 12 22 - 26 it R/hr 13 22 - 26 [t R/hr 14 22 - 25 R/hr 15 23 - 271 R/hr Building 16 22-27ji R/hr 25 17 20- 27 ji R/hr 18 20 - 25 [L R/hr 19 22 - 25 t R/hr 201 1

21-25[ R/hr "1 _

21 - 30 Lt R/hr

Figure 17: S-18 to S-15 and Building 25 to S-15 Final Survey Fixed Radiation Measurements and Results N

A S

S-18 1

2 3

4 5

6 7

8 22 pR/hr Building 25 A

25f 9

10 11 12 13 14 15 16 17 18 19 20 21 S-15 21 g R/hr 20 gR/hr 02/04/2002 21 [t R/hr 21 pi R/hr 21 p R/hr 19 p R/hr 20 R R/hr 20 [ R/hr 22 ji R/hr 22 t R/hr 130' V

22 p 21 p 21 p 21 Vt 22 pt 22p 23 p 23 p 22p 21 p 21 p 20 p 21 p R/hr R/hr R/hr R/hr R/hr R/hr R/hr R/hr R/hr R/hr R/hr R/hr R/hr

Appendix A: Final Survey Plan for S-15 Sewer Vault Pipe Trench to GA's Final Radiological Survey Report for the Sewer Line Trench, S-18 to S-13

Page 1 of 3 December 21, 2001 Prepared by: W. LaBonte Approved by:

/_ýýL

_0t Date:

//V (a,'

AL. Q. Gonzales Final Survey Plan for S15 Sewer Vault Pipe Trench This survey plan is for the Final radiological survey of the trench created during the removal of the sewer piping between sewer vaults S-15 and S-13.

Background Information and Classification

Background

The sewer line that connects sewer vault number S-15 to sewer vault S-13 was found to be contaminated with radioactive material. The sewer line was excavated, disposed of as radioactive waste, and replaced with new piping. During the excavation, an unknown, unidentified, abandoned sewer vault was discovered between sewer vaults S-15 and S-13. This sewer vault was found to be contaminated and was removed and disposed of as radioactive waste. This trench is approximately 600 ft long by 3 feet wide and up to 10 feet deep.

Classification Although there was no known loss of pipe integrity, and elevated activity levels were not detected following pipe removal, this trench is classified as a Non-Suspect Affected Area for radiological survey purposes due to the high levels of activity found in the sludge inside of the sewer piping.

The area where the unmarked/unidentified sewer vault was found, (approximately 15 meters long),

is classified as a Suspect Affected Area due to the high levels of contamination in this vault and on the tree roots that invaded this vault.

Survey Objectives and Responsibility The purpose of performing a confirmatory survey is to demonstrate that the Final Survey performed by GA Health Physics technicians was effective in identifying the radiological conditions of the area.

Release Criteria (per GA Site Decommissioning Plan)

Exposure Rate Measurements The guideline value for exposure rates measured at I m above the surface is 10 [tR/hr above background.

Soil Criteria (soil limits apply to roof gravel, concrete rubble and asphalt rubble)

The release criteria for soil are specified in the Site Decommissioning Plan and summarized below.

The values presented below are above background levels.

S-15 Sewer trench.wpd

Page 2 of 3 Cs-137 Co-60 Enriched Uranium (U-234 plus U-235)

Thorium (Th-232 plus Th-228)

Sr-90 15 pCi/g 8 pCi/g 30 pCi/g 10 pCi/g 1800 pCi/g If multiple nuclides are present, the sum of the ratios of the concentration of each Radionuclide to its respective guideline must not exceed 1. If other nuclides are encountered, notify HP Management for release criteria.

Alert Levels If the following "alert levels" are exceeded, notify HP Management so an evaluation can be performed to determine if increased survey coverage or decontamination is required.

Exposure Rate Measurement Exposure rate measurements at contact (1-2" above the surface) and at im above the surface: 25 ltR/hr.

Soil Samples Any Radionuclide above natural background levels (see HP-40 for background levels). All soil sample results must be reviewed by Laura Gonzales or Bill LaBonte.

Final Survey Requirements The minimum final survey requirements for S-15 Sewer Pipe Trench are as follows:

S-15 Sewer trench.wpd

Page 3 of 3 Final Survey Requirements for S-15 to S-13 Pipe Trench Area Gridding Exposure Rate Fixed Exposure Soil Samples*

Scans Rate Measurements S-15 Sewer Pipe Yes, 2m 100% of all 1 fixed Take I soil sample at 0 Trench grids trench surfaces measurement 6" depth every 2 m in the Non-Suspect with a 2" X 2" every 2 m with a pipe trench floor. Take 1, Affected Area NaI(Tl) detector 2" X 2" NaJ(Tl) 0-6" sample on each held within 1" detector held I m trench wall at the height of the surface, from the surface.

of the pipe (6" to 8" from floor) at the same location as the trench floor samples.

S-15 Sewer Pipe Yes, 2m 100% of all I fixed Take 1 soil sample at 0 Trench grids trench surfaces measurement 6" depth every 2 m in the Suspect with a 2" X 2" every 2 m with a pipe trench floor. Take 1, Affected Area NaI(T1) detector 2" X 2" NaI(TI) 0-6" sample on each held within 1" detector held 1 m trench wall at the height of the surface.

from the surface.

of the pipe, I m from the trench floor and 2m from the trench floor at the same location as the trench floor samples.

Additional soil samples will be required at locations with elevated exposure rates.

Documentation Every survey conducted must be documented on a daily basis on a drawing showing the approximate locations surveyed. Include the results (including units), the technicians' signature, date, instrument(s) used, efficiency, background readings (if applicable) and any other applicable information.

S-15 Sewer trench.wpd

ML020430517

Text

Subject:

Subject:

Dear Ms. Adams and Ms. Kwok:

Enclosure:

Background

Background

Background

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