Mr. Snyder, from the Air Force Center for Environmental Excellence (AFCEE), introduced himself and convened the meeting at 7:00 PM.

Mr. Snyder explained that Engineering Evaluation/Cost Analysis (EE/CA) was a more expedient way, in the Superfund process, of addressing sites and contaminants. He displayed a slide that listed the sites that Ms. Rustad would discuss in greater detail during her presentation (see attachment #1). Mr. Snyder then displayed a map that showed the locations of the study areas. He noted that tonight’s meeting would focus on soils, not groundwater.

Mr. Snyder stated that, as part of the Superfund process, remedial actions would be implemented at sites that required actions to be taken to remove contaminants from the environment. He noted that not all Superfund sites required remedial action. Mr. Snyder stated that Landfill 1 (LF-1) was an example of a site where a remedial action was taken. He explained that a decision had been made to cap this site. The decision, which was agreed upon by the United States Environmental Protection Agency (US EPA) and the Air Force, was ultimately included in the record of decision (ROD) document.

Mr. Snyder explained that the removal actions would be taken to remove and treat some of the soil before the completion of the ROD. The removal actions presented an opportunity in the Superfund process for short-term actions to minimize or eliminate site contamination.

Mr. Snyder stated that the Air Force was proposing the asphalt batching technique. He explained that this technique stabilized and prevented mobility of the contaminants. He noted that the material would be used for paving, which was a common practice among asphalt suppliers throughout the state. Mr. Snyder stated that an EE/CA document would be developed to document decisions made regarding short-term removal actions and to encourage public involvement. Following the EE/CA and cleanup action, a site would be addressed in a decision document and ultimately closed-out in the Superfund process. Mr. Snyder displayed a slide that briefly explained the purpose of an EE/CA. He stated that the EE/CA process provided an opportunity for public input into the decision-making process. He also noted that Ms. Rustad would provide a brief summary of the history of each site, as was also explained in the fact sheet that had been distributed (see attachment #2).

Ms. Rustad, from (HLA), stated that there were seven sites involved in the EE/CA process, six of which dealt with surface and sub-surface soils. She stated that the seventh site dealt with soil at depths of 10 to 22 feet below ground surface.

Chemical Spill 5 (CS-5)

Ms. Rustad reported that CS-5 was the location of a former weapons repair shop for the United States Army that had been in operation from 1941 to 1946. She stated that this site had also served as a refueler maintenance shop and spray paint shop for the United States Air Force from 1955 to 1967. Ms. Rustad reported that there were three areas of contamination. She listed the contaminants of primary concern at each area: Area 1: lead; Area 2: polychlorinated biphenyl (PCBs), and Area 3: a combination thereof. She reported that sampling results indicated that fuel-related contaminants, PCBs and lead are present in the surface soils and may pose a risk to human receptors. Ms. Rustad pointed to the location of CS-5 on a map.

Ms. Walker asked Ms. Rustad to define the term "weathered asphalt." Ms. Rustad defined weathered asphalt as asphalt that has been weathered and not maintained over the years. Ms. Walker asked if the asphalt was "broken up and crumbling." Ms. Rustad replied that it was.

Chemical Spill 11 (CS-11)

Ms. Rustad reported that CS-11, a former pesticide storage and mixing shop for the Air National Guard (ANG) and the Army National Guard (ARNG), had been in operation from 1970 to 1983. She stated that pesticides used for insect control had been spilled on the asphalt pad during mixing and then washed off the edge of the pad onto the surrounding soils. She reported that dieldrin and metals, identified in surface soils at this site, might pose a potential risk to ecological receptors. Ms. Rustad pointed to the location of CS-11 on a map.

Fuel Spill 18 (FS-18)

Ms. Rustad reported that FS-18 was a former World War II motor pool and transfer site. She stated that there were four underground storage tanks (USTs) at this site that contained diesel fuel and motor gasoline; the USTs had been removed in 1985. She also noted that at this site five leaching wells and four vehicle maintenance pits were identified; these had been removed during the Drainage Structure Removal Program (DSRP) in 1996. Ms. Rustad reported that fuel-related contaminants have been identified in the drainage course that received runoff from FS-18. The contaminants were detected in the surface and shallow sub-surface soil at depths up to six feet below ground surface, and may pose a risk to human health and ecological receptors.

CS-4 United States Coast Guard (USCG)/FS-1 (USCG)

Ms. Rustad noted that CS-4 (USCG) and FS-1 (USCG) were not related to the CS-4 and FS-1 groundwater plumes. She stated that these sites were located near Hangar 128, which was primarily used for aircraft maintenance. She reported that there had been two aviation gasoline spills at the hangar. Ms. Rustad also reported that fuel-related hydrocarbons and metals had been identified in shallow soils, which may pose a potential risk to human health and ecological receptors. She pointed to the location of CS-4 (USCG)/LF-1 (USCG) on a map.

FS-4

Ms. Rustad noted that there is potential deep contamination at the FS-4 site. She stated that FS-4 consists of an area surrounding a former fuel pump house located on the base airfield. Ms. Rustad reported that at this site there were USTs that contained aviation gasoline; one of the USTs had failed a leak test in the late 1980s. This site was recommended for an EE/CA when the USTs were removed in 1994, at which time field screening results indicated volatile contamination in deeper sub-surface soil at depths of 10 to 22 feet below the ground surface. She also noted that there was a possibility of residual fuel contamination in the deep sub-surface soil; at this time, however, the types and extent of contamination was unknown. The proposed alternative would address the data gaps and would be designed to determine the extent of the contamination at this site. Ms. Rustad pointed to the location of FS-4 on a map.

FS-7

Ms. Rustad stated that FS-7 was a fuel spill located near the northwest rotary. She reported that fuel oil had been released from a UST that had been removed in 1985. She stated that the fuel-related contaminants had been identified in surface soil and were believed to pose a potential risk to human health and ecological receptors. Ms. Rustad pointed to the location of FS-7 on a map.

Drum Disposal Operable Unit (DDOU)

Ms. Rustad stated that the DDOU consisted of a clearing in a wooded area near the former Massachusetts Military Reservation (MMR) sewage treatment plant. She stated that drums were discovered on the ground surface at this site in 1994. The drums had since been removed, the contents had been analyzed, and the drums were sent off-site for disposal. Ms. Rustad reported that pesticides, metals, and semi-volatile organic compounds (SVOCs) were identified in shallow soil samples. She stated that further characterization of this site was also proposed; the extent of the contamination was not known.

Ms. Rustad then displayed a table that summarized the sites, the contaminants of concern, the maximum soil concentrations, and the estimated volume in cubic yards of soil.

Questions and Answers

Ms. Walker referred to the residual fuel contamination mentioned at the FS-4 site and asked if it was possible that there was a plume at that location. She specifically asked about the groundwater monitoring at FS-4. Ms. Rustad replied that this EE/CA assessed the soil contamination and she was unable to answer questions related to groundwater. Ms. Walker then asked if groundwater monitoring had been done in this area to assure that there was not a plume there. Mr. Snyder replied that the Southeast Regional Groundwater Operable Unit (SERGOU) investigation covered most of this part of the base, and it was determined that FS-4 was not contributing. Ms. Walker asked if that was also true of FS-7 where 11,000 gallons of fuel oil had spilled. Mr. Snyder replied that this was true.

Development and Overview of Removal Action Alternatives

Ms. Rustad briefly explained the three alternatives that were developed to address the seven sites:

Alternative 1: On-Base Thermal Desorption and/or Off-Base Treatment and Disposal for Six Sites

Alternative 2: On-Base Asphalt Batching and/or Off-Base Treatment and Disposal for Six Sites

Alternative 3: Off-Base Treatment and Disposal for Six Sites

Ms. Rustad noted that all three alternatives also include in-situ treatment for FS-4, meaning that there would be no removal of contaminated soil, rather the soil would be treated in place. Ms. Rustad then explained the general components of the potential removal action alternatives. She again noted that there was a data gap at FS-4, in that the type and quantity of contamination was unknown; it was possible that a removal action would not be warranted at this site. Ms. Rustad stated that in-situ soil vapor extraction or a bioventing system has been proposed, as part of the EE/CA, to remediate the deeper soil at FS-4. She also noted that site restoration would include back filling and repairing any impacted wetlands.

On-Base Thermal Desorption

Ms. Rustad displayed a flow chart of the thermal desorption process. She explained that this was a low temperature process that uses indirect heat to vaporize and remove contaminants from the soil. She stated that following the procedure, the soil, if determined clean, would be used as backfill material. If the soil were not determined clean, it would either be reprocessed or sent off-base for disposal. Ms. Rustad noted that this process included an air pollution control system.

Asphalt Batching

Ms. Rustad explained that with this method, the excavated soils would be characterized to determine if they were safe for the asphalt batching process. She noted that some of the levels of contaminants in Area 1 and Area 2 at the CS-5 site may not be acceptable for asphalt batching; they would be characterized separately from the other soils to assure that they are acceptable. Ms. Rustad stated that unacceptable material would be sent off base for treatment and disposal. Acceptable material would be screened and crushed, an asphalt emulsion would be added to bind the contaminants to the soil and, after curing for 72 hours, it would be used as a sub-grade base paving material.

Excavation and Off-Site Disposal

Ms. Rustad explained that with this alternative, the soil would be excavated and sent off-site for treatment and/or disposal.

In-Situ Treatment

Ms. Rustad explained that in-situ treatment consisted of a low-flow soil vapor extraction system, or a bioventing system. She noted that this system would only be installed if pre-design investigations indicated that a removal action was necessary. She then displayed a slide that showed a conceptual section view of the low-flow soil vapor extraction system.

Ms. Rustad explained that there were two methods of addressing deeper sub-surface soils. She stated that the contaminants could either be physically stripped from the soil by injecting high flow rates of air into the soil, or lesser amounts of air could be injected and lower flow rates could be used to promote biological degradation of the contamination.

Questions and Answers

Ms. Walker inquired about the air monitoring for all three processes. Ms. Rustad replied that air monitoring for all three processes would be conducted during the excavation phase. It would also be conducted during each of the three processes to ensure that emissions of both volatile contaminants and dust would be monitored. Ms. Walker asked if it was correct that thermal desorption treated organic compounds effectively, but did not effectively treat inorganic compounds. Ms. Rustad replied that this was correct. Ms. Walker then asked what percentage of compounds was inorganic and what percentage was organic. Mr. Snyder replied that inorganic compounds in soil would not volatize in this temperature range. He stated that these removal actions were organic, not necessarily volatile, but organic. Ms. Walker commented that if only a small amount of the compounds were inorganic, it was then irrelevant that this treatment did not treat inorganics. Ms. Rustad reported that there was lead at 7615 parts per million (ppm) at CS-5, and there were also inorganic contaminants at CS-11, CS-4, FS-1, and at the DDOU. Ms. Walker again asked if a percentage of inorganic and organic contaminants had been identified. Mr. Karson encouraged Ms. Walker to repeat her question during the public hearing portion of the meeting and an answer would be provided in the Action Memorandum.

Mr. Pompilio asked how long the Air Force had been addressing these seven sites. Mr. Karson replied approximately six years. Mr. Pompilio then asked how many years it would take before the sites would be remediated. Mr. Snyder replied that the soil would be excavated in the latter half of the year 2000. He stated that there was approximately a year and a half of soil excavation work to be done. Mr. Pompilio asked if the Air Force knew the extent of the soil contamination. Mr. Snyder replied that with the investigations conducted at this site, which included interviews, record searches, and sampling events, the Air Force believes it has defined the extent of the soil contamination. Mr. Pompilio then asked if, in the year 2000, the Air Force would continue to investigate and explore for more areas that might be contaminated. He asked if it was correct that the Air Force had definitely not determined where all the contamination was located. Mr. Snyder replied that, for the seven sites being discussed, two would require additional investigations as the designs were completed. The investigations of the other sites were complete.

Mr. Pompilio noted that he was not familiar with the base, and suggested that Ms. Rustad mention reference points to help better identify the locations of the sites on the map. He then asked Ms. Rustad to identify the "worst" site. Ms. Rustad pointed to the CS-5 site, which she noted has two separate areas of contamination.

Mr. Dow asked where the centralized asphalt batching facility would be located. He commented that the community had a concern about the facility being located near off-base residences or near on-base military housing. Mr. Snyder replied that engineering evaluations were being conducted to determine the most effective location for the asphalt batching facility. He noted that exposure concerns would be taken into consideration. He also stated that the facility would not be located near the neighborhood borders of the base, rather in the interior of the base.

Ms. Rustad continued with her presentation, by noting that, following the development of the alternatives, an evaluation of the alternatives had been conducted. She briefly explained the evaluation criteria. Ms. Rustad reported that the Air Force preferred Alternative 2: On-Base Asphalt Batching and/or Off-Base Treatment and Disposal for Six Sites and In-situ Treatment for FS-4. She listed the components of this alternative and explained why Alternative 2 is the preferred alternative of the Air Force. She then displayed a slide that showed the schedule for the EE/CA process. She noted that the EE/CA is available for public review at the Bourne, Falmouth, Mashpee, and Sandwich public libraries. Information could also be obtained via the AFCEE/MMR website at http://www.mmr.org or the Community Involvement Office at (508) 968-4678.

Questions and Answers

Mr. Pompilio asked what was being done to address the plumes that were deep in the soil. Mr. Snyder replied that some alternatives for treating groundwater plumes have been implemented, and others were in the design phase. He stated that the groundwater plumes were being addressed through similar, yet separate, processes. Mr. Pompilio asked if any of the contaminants had been removed. Mr. Snyder replied that some contaminants had been removed, and noted FS-12 as an example. Mr. Pompilio asked how many plumes are on the base. Mr. Snyder replied that there are 11. Mr. Pompilio asked how long it would take to clean up those plumes. Mr. Snyder replied that it would take decades to remove the majority of the contamination from the plumes.

Mr. Karson adjourned the meeting at 7:40 PM.

A formal public hearing followed this meeting.