ML20057D728
| ML20057D728 | |
| Person / Time | |
|---|---|
| Issue date: | 09/22/1993 |
| From: | Bouwens M, Kinneman J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20057D718 | List: |
| References | |
| REF-QA-99990001-930922 99990001-93-13, NUDOCS 9310050265 | |
| Download: ML20057D728 (10) | |
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U.S. NUCLEAR REGULATORY COMMISSION REGION I Report No.
9999990001/93-013 License No.
None Docket No.
None Inspection At:
U.S. General Service Administration Federal Property Resources Center 670 Arsenal Street Watertown. Massachusetts Inspection Conducted: June 15 and 16.1993 Inspector:
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Mark R. Bouwens date Health Physicist Approved By:
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[Johy D. Ki'nneman date Qep: arch, Development, and Decommissioning Section Insocction Summary:
Routine. announced safety insnection conducted June 15 and 16.1993 (Inspection No. 99990001/93-013L Areas Inspected:
Organization for decommissioning; facilities and equipment; posting and labelling; instrumentation and calibration; internal radiation protection; remediation activities; waste disposal; and radiological characterization.
Results:
One deviation from approved procedures was identified: failure to restrict site access to individuals that were briefed on the RWP for the site and to keep adequate records ofindividuals that were briefed on the RWP.
@M 9310050265 930922 REG 1 GA999 EUSDODAE 99990001 PDR D
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DETAILS 1.
Persons Contacted
- Dr. Ian Osgerby, Project Manager, Army Corps of Engineers, New England Division
- Peter Cornetta, Radiation Safety Officer, U.S. Army Research laboratory (ARL)
- Captain Joy Howard, Alternate Radiation Safety Officer, ARL
- Paul Black, Alternate Radiation Safety Officer, ARL
- Alex Feldman, Radiological Control and Safety Officer, Scientific Ecology Group
- Robert Chase, Technical Monitor, ARL
- Tom Kivett, Project Supervisor, Morrison-Knudson (MK)
- Mark Hellstrom, Superintendent, MK
- Jim Hensch, Site Health Physicist, Scientific Ecology Group (SEG) l Betsy Langille, Analytical Services Coordinator, SEG t
Greg Mcdonald, Analytical Services Technician, SEG Albe Simenas, Project Manager, Massachusetts Department of Environmental Protection John Robinson, Health Physicist, Interlink (MADEP contractor)
- Denotes those present at exit interview.
===2.
Background===
The Watertown Arsenal GSA property (GSA property) is northeast of the current U.S. Army Research Laboratory (ARL) and was formerly the northeastern part of the
_t Watertown Arsenal. The ARL was renamed from the U.S. Army Materials Technology I2boratory (MTL) on October 30,1992. The GSA property is about five hectare (12 acres) and includes four buildings and an area known as the ' burn pit'. The property was used by the U.S. Atomic Energy Commission (AEC), the Manhattan Engineer District (MED), and the Department of the Army for the packaging and storing of l
radioactive waste, burning of uranium scrap, and staging of radioactive waste shipments from the 1940's to the 1960's. The burning of uranium scrap took place in the burn J
pit.
The use of source material was authorized at the GSA property by AEC License No. SUB-238 from May 9,1961 to January 17,1974 when the area was released for unrestricted use by the AEC. The release of the GSA property was based on a
'U.S. Army radiation safety survey dated October 7,1973. Title to the property was transferred to the U.S. General Services Administration (GSA) on August 16, 1968.
i The U.S. Department of Energy (DOE) surveyed the GSA property from July 13,1981 4
to September 4,1981 as part of a program to determine the condition of sites formerly utilized by MED and AEC for work involving the handling of radioactive materials.
The results of the survey were published in a DOE report, dated October'1983 (DOE Report). The survey results indicated the presence of radiological contamination on the c
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GSA property above current NRC guidelines for release for unrestricted use. However,
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DOE determined that there was insufficient data to provide the DOE with authority to i
conduct remediation activities at the GSA property under the Formerly Utilized Sites Remedial Action Program.
i At the request of GSA, the U.S. Army contracted Chem-Nuclear Systems, Inc. (CNSI) to remediate the GSA property. CNSI conducted remediation activities at the site from October 1988 to June 1989 at which time remediation activities were prematurely terminated because petro-hydrocarbons were detected in the water in the burn pit.
CNSI then surveyed the GSA property from June 18,1990 to August 6,1990. The results of the survey were published in a CNSI report, dated October 1990 (CNSI Report). The survey results indicated the presence of radiological contamination on the GSA property above current NRC guidelines for release for unrestricted use. In May 1992, at the request of GSA, the U.S. Army Corps of Engineers, New England Division (NED), agreed to remediate the GSA property. NED submitted a Scope of Work (SOW) for remediating the site on October 27,1992. Region I determined that the SOW was acceptable on April 15, 1993.
3.
Oreanization for Decommissionine NED agreed to remediate the GSA property for GSA in May 1992. The remediation activitics are funded through the Formerly Used Defense Sites program (FUDS). NED keeps ARL apprised of the status of the site. NED has contracted Morisson-Knudsen (MK) to conduct the remediation activities. MK has contracted Westinghouse Scientific Ecology Group (SEG) to provided health physics services necessary for the remediation activities on the site. The MK and SEG personnel conducting remediation activities at the GSA property are also conducting remediation activities at ARL.
4.
Facilities and Eauipment A trailer is used for office space on-site. One of the buildings on-site is a shed that is used as a dress out area and for storage. Additional space is used at ARL for offices, dosimetry, analytical equipment, radiation survey instrumentation, training, and storage.
j The site is enclosed by a fence that approximates the perimeter boundary. A second fence separates the area of the three large buildings from the majority of the site, including the burn pit area. The two fences appeared intact. An additional fence j
defm' iry: 6 burn pit area has been partially dismantled to conduct remediation activities.
A backhoe is used for excavation on-site. The backhoe uses a large path leading from the asphalt area adjacent to Building 235 to the burn pit area so the backhoe can be parked on the asphalt. The backhoe must be parked on a solid surface to prevent oils from dripping on the soil while the backhoe is undergoing maintenance or not in use.
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5.
Postine and Labelling The burn pit area, the path leading from the dress out area (the shed) to the burn pit area, the parking area of the backhoe, and the path leading from the burn pit area to the parking area of the backhoe are roped off or fenced and appropriately posted. The perimeter fence of the site was appropriately posted.
There are locations of contamination outside of the burn pit area that have been identified. The areas are included in the roped off area. A radioactive waste storage area is located on the asphalt next to Building 235. The annex in Building 235 was used as a radioactive waste storage area for waste produced by characterization activities conducted by CNSI i
in 1990. Both areas were roped off and appropriately posted.
6.
Instrumentation and Calibration Soil and rubble (debris) is scanned with a Ludlum Model 2350 Data Logger smvey 2
instrument, equipped with a 550 cm gas proportional detector. The detector is operated in the continuous gas flow mode with the high voltage setting. This configuration enables the instrument to detect both alpha and beta radiations.
Soil samples are counted on a Canberra Genie microcomputer hyperpure germanium gamma spectroscopy system. The system was calibrated with one liter sand equivalent americium-241 and cobalt-60 reference standards, traceable to the National Institute of Standards and Technology (NIST). The system is calibrated with the standards once per year or when warranted by maintenance on the system. A quality control check of the system is performed daily with one liter water equivalent americium-241 and cobalt-60 reference standards, traceable to NIST.
The soil samples arc dried and weighed prior to counting to accurately report the measured concentration on the basis of dry weight. The balance used to weigh the l
samples is checked for linearity once per month. All samples are labelled and archived for future reference.
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7.
Internal Radiation Protection Air sampling was not conducted during the excavation activities as stated in Section 02212, Part 3.1.2 of the SOW. However, the excavated soil was saturated, therefore reducing the possibility of airborne contamination.
Air sampling was conducted when dried soil was being handled (e.g. when the debris is turned during the drying process). In a telephone conversation, on June 24,1993, the inspector requested that NED submit a revision to the SOW to describe the changes in procedure, noted by the inspector, for air sampling during excavation. The NED responded in a letter, dated June 28,1993. The information submitted accurately describes the procedures noted by the inspector during the inspection.
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5 Air sample results were reviewed by the inspector.
The results indicate the concentrations of DU in the air were below the MPC value. The air pump was calibrated on May 15,1993 and is scheduled for recalibration on November 18,1993.
The air flow rate can be monitored from a dial gauge and a column gauge.
8.
Remediation Activitiej The trailer is located next to Building 235 within the secondary fence. Access to the site is controlled by having each individual entering the site pass through the trailer.
An individual entering the site for the first time is briefed on the Radiation Work Permit (RWP) for the site. A sign-off sheet is signed by the individual indicating that the person was briefed. Additionally, every time an individual enters orleaves the site that individual must sign-in or sign-out, respectively, on a sign-in/out sheet located in the trailer. The inspector compared the RWP sign-in/out sheets for June 15 and 16,1993 with the RWP briefing sign-off sheet. Five of the names that appeared on the RWP sign-in/off sheet were not on the RWP briefing sign-off sheet. One of the individuals that had not signed the RWP briefing sign-off sheet was present. The individual had been briefed but had neglected to sign the sign-off sheet. The other individuals that had.
not signed the RWP briefing sign-off sheet were not available for interview at that time.
Allowing individuals on-site without signing the RWP briefing sign-off sheet and allowing access to the site to individuals not briefed on the RWP for the site is a deviation from the approved procedures in the SOW.
To enter the burn pit area, booties and rubber foot covers are worn by workers and observers. Additional protective clothing is used by some workers that have to survey the dry soil. When exiting the area, the rubber foot covers and the booties are removed. The booties are disposed as radioactive waste and the foot covers are left for reuse. Hands and feet are frisked with a GM detector equipped with a pancake probe before exiting the burn pit area.
The subsurface fill matenal located on-site is mostly building rubble that starts from the 0-0.3 m (0-1 ft) level and continues down about 3 m (10 ft). The rubble consists of sheets of metal, clay brick, and pieces of concrete block that range in size up to 4 nf (140 ft').
The water level of the area is currently about one foot below the surface in the burn pit.
At times during the year, portions of the site, including the burn pit, are underwater.
The water in the burn pit was sampled prior to beginning the excavation activities. The pH of the water was determined to be neutral and the concentration of radionuclides in the water were below NRC effluent limits.
NED conducted a characterization survey, prior to excavation, in the burn pit area and the area of the two hot spots identified in the SOW. The characterization data for the survey was reviewed by the inspector. The data indicated the presence of radioactive
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6 contamination in the burn pit area and the areas of the two hot spots and identified a third hot spot of radioactive surface contamination located adjacent to the burn pit area.
Radioactive contamination levels in the soil were measured as high as 100,000 picoeuries per gram (pCi/g)* and 34,770 pCi/g* at two locations. The latter location l
is the third hot spot. Six other soil samples had radioactive contamination levels ranging from 32.7 pCi/g* to 2,056 pCi/g*. The CNSI Report indicated that the highest levels of radioactive contamination on the site we.re 330 pCi/g total uranium in one location of the burn pit. The soil was also analyzed during the current characterization activities to determine if the uranium in the soil is depleted uranium (DU) or natural uranium. The results reportedly show that the uranium in the soil is DU. Most of the radioactive contamination that has been located is in the physical form of metal fragments, filings, or chips. It is believed that there is DU ash in some of the soil, however, none had been confirmed as of the date of the inspection.
The remediation activities in one of the two hot spots identified in the SOW have been completed. The hot spot is now a pit approximately 1.2 m (4 ft) deep and 3.4 m (11 ft) in diameter.
The contractors estimate that approximately 11 m' (400 ft') of radioactively contaminated debris has been removed from this location. The third hot spot consisting of only surface contamination was remediated. No excavation in this l
location was necessary.
The DU burning operations that took place in the burn pit from the 1940's to the 1960's were conducted on top of a concrete pad that was removed during previous remediation I
activities. It was noted in historical documents that some spills of DU occurred in this area and that the burning activities contributed to DU in the soil of the burn pit area.
One document states that the radioactive surface contamination resulting from the burning activities was bulldozed under the surface to remove the hazard. The burn pit has been excavated during the current activities to about 2.4 m (8 ft) deep and 6.1 m (20 ft) in diameter. The soil from the bottom of the pit is still contaminated with DU.
The bulldozing would account for some of the subsurface contamination, but probably not to.the extent found in the burn pit, especially the areas that were once under the concrete pad. The NED speculates that the DU was transported through gaps in the rubble that may not have been filled with soil when the fill (the rubble) was placed on the site. It is assumed that because of these possible gaps, the rain, and the high water table on the site, the DU was able to transport through the subsurface volume more rapidly than under conditions of uniform soil density.
The water in the burn pit was not pumped out prior to excavation activities as stated in Section 02212, Part 3.1.1 o' the SOW. The NED and their contractor believe that it would not be possile to pump the water out of the burn pit because of the high water
" Concentration of thorium-234 activity in the soil. Thorium-234 is a decay product of uranium-238,
7 table. The' water in the burn pit was sampled during the excavation activities. In a telephone conversation, on June 24,1993, the inspector requested that NED submit a revision to the SOW to describe the changes in procedure, noted by the inspector, for pumping water out of the bum pit during excavation activities. The NED responded in a letter, dated June 28,1993. The information submitted accurately describes the procedures noted by the inspector during the inspection.
Water sample results were reviewed by the inspector. The results indicated radioactive concentrations in the water were below the NRC effluent limits.
The contractor is using a backhoe to excavate the burn pit. The excavated debris from the burn pit is saturated. The backhoe operator allows most of the excess water in the-bucket of the backhoe to drain before dumping the load into a dumpster located adjacent to the burn pit. The dumpster has one side removed and is angled toward the burn pit so that water from the debris is allowed to drain back into the burn pit. The debris is left in the dumpster until dry. Two dumpsters were used for the drying of the debris.
i Additionally, some debris was placed on the edge of the burn pit to allow to dry.
During the dumping of the debris, some of the water is spilled outside of the burn pit and dumpsters.
However, as previously stated, the water was sampled during excavation activities and determined to have radioactive concentration levels below NRC i
effluent limits and the workers are taking appropriate precautions to minimize spills.
Approximately six large concrete blocks were removed from the bottom of the burn pit.
The blocks were set in a separate area adjacent to the burn pit to allow to dry. The blocks ranged in size from about 0.3-4 m'(10-140 ft'). One of the blocks was surveyed in one location by the contractor and found to have approximately 1,000 disintegrations 2
per minute per 100 centimeters squared (dpm/100 cm ). The large concrete blocks will 2
be surveyed for radioactive surface contamination against a limit of 5000 dpm/100 cm,
Surface contamination identified above this limit will either be removed or the block j
will be disposed of as low level radioactive waste.
j The debris in the dumpster is piled about 0.6 m (2 ft) high. The drying time for the debris is a couple of days depending on the weather conditions. Some of the moisture in the debris evaporates by the heat of the sun, however, the contractor uses two 350,000 British Thermal Units (BTU) heaters on each dumpster to add to the heating.
The heaters blow hot air on the bottom and sides of the dumpsters to heat tl.eir metal bodies, therefore, providing additional heat energy for the evaporation process. The drying procedure was to be improved further by laying two metal pipes along each side of the inside of the dumpster walls prior to filling the dumpsters with debris. The heaters would then be used to blow hot air through the pipes to provide heat more directly to the debris and decrease the drying times. The backhoe is used during the drying process to turn the soil over periodically to allow for a more even distribution of heat to the debris in the dumpsters.
8 After the debris is dried, a preliminary surface survey of the debris is conducted with 2
a Ludlum Model 2350 with a 550 cm probe. The survey results have indicated that all 2
debris dried in the dumpster was contaminated with over 5000 dpm/100 cm. All debris with surface contamination above this limit will be packaged for disposal as low level radioactive waste. If the preliminary survey of the debris in the dumpster indicates 2
surface contamination levels below 5000 dpm/100 cm then the debris will be spread out on a sheet of plastic into a layer a couple of inches thick. The debris will then be resurveyed. If the survey results show that the surface contamination levels are below 2
5,000 dpm/100 cm, soil samples will be taken and compared against a soil concentration limit of 35 pCi/g total uranium in the soil. The contamination levels in the bottom of the pit at the time of the inspection were reported to be approximately 1,000 pCi/g.
Prior to the packaging of contaminated debris, the debris is filtered through a grating to screen out large pieces of rubble. The grating is a series of V-shaped metal bars welded to a frame approximately 3.7 m x 3.7 m (12 ft x 12 ft)in size. The screened out rubble is piled in the burn pit area and will be surveyed at a later date to determine its disposal requirements. The NED plans to decontaminate some of the large pieces of rubble to reduce the volume oflow-level radioactive waste. The remaining filtered debris is packaged in B-25 storage containers.
The remediation activities that were conducted in 1989 by CNSI were terminated because an oily sludge deposit was discovered in the soil in the burn pit. Analysis of the sludge indicated the presence of potentially hazardous materials and DU. During the current remediation activities at the burn pit, NED has found a black murky substance in the water.
Analysis of the water indicated the presence of organic material. Concentrations of petro hydrocarbons, cadmium, and nickel have been measured in samples taken from the burn pit; however, the concentration levels were reportedly below the limits established in MADEP guidelines. No mixed waste has been generated on the site as a result of the current remediation activities.
9.
Waste Disposal Forty-one 55-gallon drums of waste from the previous CNSI characterization activities had been stored in Building 235. NED has sampled and disposed of the drums according to type of waste.
The excavated soil from current remediation activities has been sampled and concentrations of technetium-99 (between approximately 2 pCi/g and 10 pCi/g) and carbon-14 (1 pCi/g) were reported by NED's contractor. NED planned to dispose of the waste at Envirocare, however, the concentrations of technetium-99 and carbon-14
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are above the limits that Envirocare can store under their current license.
The radioactive waste is currently being stored in B-25 storage containers located in an area on the asphalt next to Building 235. Since there was no obvious source for such j
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9 contamination NED plans to carefully review the analytical results and confirm their accuracy. The inspector measured between 10-15 microRoentgen per hour ( R/hr) at contact with the B-25 storage containers.
10.
Radiological Characterization Stud _y i
The annex area in Building 235 was used to store 4155-gallon drums of waste from CNSI characterization activities in 1990. The NED has removed the drums. A preliminary survey of the area was conducted to identify radiological contamination that may be present. The survey results indicated that no contamination was present. The area will be gridded and resurveyed as part of the termination survey of the site.
Three manholes have been located on the GSA property. The manholes are part of the on-site sewer system.
The system consists of one sewer line that leads from Building 235 to a pump house outside of the perimeter fence of the property. The sewer line appears to only be for a shower / toilet / sink facility located in Building 235.
i The NED plans to sample the sediment in the manholes as part of the characterization of the site.
There are several areas identified in the ANL Report where surface measurements indicate there may be radiological contamination of the soil. The inspector briefly surveyed the areas with a Model 19 microR meter. The survey showed radiation levels in the range from 10-30 pR/hr. The levels are consistent with past surveys and indicate that there is no immediate radiation hazard.
Sawins Pond Brook flows across and under the front (the southern tip) of the GSA property. At the entrance of the site four pipes approximately 0.3 m (1 ft) in diameter terminate at the brook. Three of the pipes appeared to be capped with concrete. The NED believes that the pipes are or were storm sewer lines from the property adjacent to the GSA property (the condominium property) but will investigate the pipes further to determine if radiological characterization is necessary.
Tis ncrthern tip of the site outside of the perimeter fence was investigated by the inspector.
The area is overgrown with extremely dense vegetation that includes obstacles such as briars and poison ivy. The NED plans to remove all vegetation from this area, except the trees, so that radiological characterization activities can be conducted. Concrete structures discussed in the CNSI Report are located in this area.
One of the structures was almost completely uncovered. Two similar structures located in the proximity of the first were almost completely covered with soil and vegetation.
The structures are odd shaped concrete slabs, approximately 1.5 m x 3.4 m (5 ft x 11 i
ft) in size, with two metal U-shaped bars inset into depressions and level with the surface of the concrete. It was not possible to determine the exact purpose of the structures, however, they appear to be a type of anchor.
The NED plans to radiologically characterize the structures, including determining if they are vaults.
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10 Several maps of the GSA property indicate that there were cornerstones marking the current property boundaries. The inspector was unable to locate the cornerstones. It is possible that they have either been removed or overgrown by vegetation. The NED plans to conduct a land survey of the site to locate the property lines of the current GSA property and " Property 20." Property 20 was the northern tip of the site that the former Watertown Arsenal was granted by the Commonwealth of Massachusetts until August 22,1951.
Documentation and survey information indicate there were several spills of DU in the burn pit area from the DU burning operations that were conducted from the 1940's to the 1960's. Atter the excavation of the burn pit is completed the NED plans to conduct a near surface radiological survey (approximately six inches deep) of the burn pit area
.j in an attempt to locate areas where spills occurred. The survey will consist of first 2
surveying the area with a Ludlum Model 2350 equipped with a 550 cm probe. The first six inches of soil will then be turned over and resurveyed, approximately three times. Additionally, subsurface samples in the burn pit area will be taken as part of the termination survey.
11.
Exit Interview The results of the inspection were reviewed with the individuals identified in Section 1 of this report.
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