LF-1 Posterboard Session and
Presentation
Welcome and Introductions: Greg Sobel, CBI Mr. Sobel, from the Consensus Bureau Institute (CBI) introduced himself and briefly explained his role as facilitator. Mr. Sobel asked the Remedial Project Managers (RPMs) to introduce themselves: Mr. Jim Snyder, the RPM for the Air Force Center for Environmental Excellence (AFCEE); Mr. Len Pinaud, of the Massachusetts Department of Environmental Protection (MA DEP), and Mr. Paul Marchessault, for the United States Environmental Protection Agency (US EPA). Mr. Sobel noted that the RPMs are the key decision makers on each of the plume decisions. He stated that the intent of the meeting was to discuss the remediation alternatives for the LF-1 plume, and added that these public meetings are designed to facilitate the involvement of the community and public in the decision making process. Mr. Sobel asked the members of the community involvement team to introduce themselves: Mr. Jerry Whitaker, public affairs specialist for the Mass Military Reservation (MMR); Ms. Ellie Grillo of the MA DEP; Mr. Doug Karson, public affairs specialist for the Installation Restoration Program (IRP), and Johanna Hunter from the US EPA. Mr. Sobel stated that the agencies were here to listen to the publics’ opinions, and answer questions regarding the proposed alternatives for the LF-1 plume. He stated that the RPMs would also be available to answer questions after the presentation. Mr. Sobel then introduced Mr. Snyder. Groundwater Recharge Process: Mr. Jim Snyder, AFCEE Mr. Snyder explained the groundwater recharge process for developing and evaluating alternatives for the plume cleanup. He displayed a cross section of the ground layers including the water table, the sandy aquifer, the silt and the bedrock. Mr. Snyder briefly explained the elevations above sea level in the Upper Cape area. He displayed a map depicting the contour lines of the Sagamore Lens. Mr. Snyder noted that the Sagamore Lens is the largest single lens on Cape Cod. He stated that the MMR is located on the highest level of the groundwater mound, and water travels downward towards Buzzards Bay. Mr. Snyder displayed a diagram of the groundwater cycle. Precipitation (snow or rain) percolates into the soil and saturates the water table. The snow and rain bring contaminants that enter at the water table, travel downward with the water, and recharge into the surface water bodies. Technologies: Mr. Snyder stated that there were two technologies being evaluated for use in treating the groundwater contamination. 1. Extraction, Treatment, and Reinjection (ETR): Mr. Snyder displayed a cartoon diagram of an ETR system. He explained that a well screen would be installed below ground surface, as well as a vault housing the controls for the submersible pump. Mr. Snyder stated that a well would be installed in an area containing volatile organic compounds (VOCs). A submersible pump pushes water up to a treatment plant and water is filtered through a carbon monitoring system to ensure that the water is clean. The organics stick to the carbon, and the filtered water is reinjected into areas in which the water is already clean. Mr. Snyder stated that reinjection and extraction is also used to hydraulically control the groundwater. 2. Recirculating Well Technology: Mr. Snyder displayed a slide of the recirculating well technology. Mr. Snyder stated that the benefit with this technology is that there is no water table draw down associated with this process. The water is reinjected in the same location from which it was extracted. Mr. Snyder stated that the water is pulled in at the bottom of the well, and it is pumped up the well mixing with air in the process. It uses all organic compounds that tend to vaporize into the air stream, allowing the water to fall back down. The air with the VOCs is stripped in a carbon unit, removing the VOCs. Mr. Snyder compared the cross section of this process to a donut. He stated that the main interest is that this process has the promise of dealing with hydraulically sensitive environments around surface water areas avoiding the issues of salt water fresh water interface or possible alteration of the flow of how the ponds receive their groundwater recharge. LF-1 Plume: Mr. Snyder displayed a map of the LF-1 for orientation purposes. He pointed out the area of the LF-1 plume and the location of the land fill. Mr. Snyder stated that the approximately 60 acres of land fill has been capped, preventing water and snow from percolating into the land fill. He displayed a slide showing the contour lines of the primary contaminants of the LF-1 plume. Mr. Snyder stated that the primary contaminants of the LF-1 plume are trichloroethylene (TCE), tetrachloroethylene (PCE), and carbon tetrachloride. The slide depicted the distribution of contaminants using color codes; gold = TCE, red = PCE, green = carbon tetrachloride. Mr. Snyder noted that some of the contour lines represent 20 ppb of certain components. He stated that the outline of the plume is a 5 parts per billion (ppb) exceedence which is the maximum contaminant level (mcl) for these compounds. Mr. Snyder displayed various slides associated with LF-1. The slides included pictures of the LF-1 cap, the polyethylene liner used to control erosion and water run-off, as well as the excavating done to control the slope. There were also slides of wells being tested. LF-1 Decision Criteria Process: Mr. Snyder explained the schedule for the decision criteria process. *See attached. How to Submit Written Comments: Mr. Snyder stated that he and the other RPMs read every comment that is received, and then explained the various means to submit written comments: Web Site: http://www.mmr.org
Analysis of the LF-1 Plume Response Alternatives: Mr. Bud Hoda, Project Officer Mr. Hoda stated that he would be briefly explaining the proposed alternatives for the LF-1 plume. He added that there was a handout available, with a more detailed explanation of each alternative. Decision Criteria Matrix Review: Mr. Hoda displayed a slide of the decision matrix criteria review and briefly explained the data. *See attached
Alternatives Strategies: Mr. Hoda displayed a slide summarizing the strategies of each alternative.
Amount of Contamination: Mr. Hoda displayed a slide comparing the amount of contamination in four of the plumes.
Estimated Percent of Mass Capture: Mr. Hoda displayed a slide depicting the percent of mass capture for each of the alternatives. Alternative Total Mass Captured
Estimated Costs: Mr. Hoda displayed a slide of the total costs for each of the alternatives. Mr. Hoda noted that alternative D was the most expensive and alternative Z was the least expensive. *See attached Alternative: Total Capture Cost: Annual Cost: Life Cycle Cost:
Threshold Criteria: Mr. Hoda displayed a chart showing data on the impacts to the following criteria; Human Health; Environment; and Compliance with applicable or relevant and appropriate requirements (ARAR’s). *See Attached A member of the audience asked what the definition of the overall protection of human environment was, and asked if the aesthetics of an area have any impact on the definition. Mr. Andy Miller of Jacobs Engineering Group stated that that would be in the socioeconomic criteria. Mr. Hoda added that they have considered that, however it is not included in this criteria. Mr. Hoda stated that he would be happy to discuss this with the audience member after the presentation. Mr. Miller stated that this evaluation is on direct impacts to human health. The audience member asked why then they had environment listed. Mr. Hoda replied that it was ecological risk. Mr. Miller explained the chart on threshold criteria stating that the first line on the chart was impact to human health. The second line represented impacts on the environment, and showed that one of the reinjection fences for alternative D would impact a sensitive upland grass area. Mr. Miller stated that the other active alternatives have dash lines on the chart which represent that they are not sure if they will impact. The audience member asked if they evaluated what the impact is of actually building the facility. Mr. Snyder stated that that data is part of the matrix and is in the primary balancing criteria. Mr. Sobel added that there was criteria that addresses the construction impacts. Mr. Dow asked if the main consideration under the human health criteria was risk of cancer. Mr. Hoda stated that they consider carcinogenic and noncarcinogenic things as well. Mr. Snyder stated that the health hazard is in the primary balance when they do the carcinogenic risk, and the risk assessment guidance. He stated that this is strictly looking at, are the pathways being changed, or are they improving exposure potential, and is a qualitative way to assess this. Mr. Snyder stated that the actual calculations of carcinogenic and noncarcinogenic health risk in the other part of the document. Mr. Sobel asked Mr. Snyder to define "pathway". Mr. Snyder stated that a pathway is a method of exposure. He stated that there must be control, elimination or a deduction of a pathway or exposure, to satisfy this criteria. Alternative A: Mr. Hoda stated that alternative A is designed to achieve a high degree of plume capture using both extraction, treatment and reinjection, and recirculating well technologies. This alternative uses ETR fences along Route 28, and recirculating wells in the Conservation Land near Red Brook Harbor and near the shoreline of Red Brook Harbor. Mr. Hoda stated that this alternative allows for the greatest plume mass capture. Alternative B: Mr. Hoda stated that alternative B only uses recirculating well technology. Mr. Hoda stated that his alternative uses recirculating wells along Route 28A, Depot Road, and near the shoreline of Red Brook Harbor. There would also be a recirculating well fence on base property, within the area of highest contaminant concentration. Mr. Hoda stated that this alternative achieves slightly less percent containment of contamination than alternative A. Alternative C: Mr. Hoda stated that alternative C includes ETR wells in the Conservation Land east of Red Brook Harbor along Route 28. Mr. Hoda stated that there will be an axial extraction well fence within the plume in the area of highest contaminant concentration. The treated groundwater would be reinjected immediately downgradient from the extraction wells within the Conservation Land and along Route 28, and north and south of the plume. Mr. Hoda stated that this alternative removes contaminants substantially initially, however in 30 to 40 years it becomes asymptotic. Alternative D: Mr. Hoda stated that alternative D uses both ETR and recirculating well technologies. This alternative includes ETR wells along Route 28. Mr. Hoda stated that three axial extraction well fences would be installed within the north lobe, the south lobe, and on-base, in the area of highest contaminant concentration. The recirculating wells are in the Conservation Land east of Red Brook Harbor and also near the shoreline of Red Brook Harbor. Mr. Hoda added that this alternative also produces the most mass removal early on in the phase. Alternative E: Mr. Hoda stated that alternative E uses ETR technology. An ETR fence would be located along Route 28 with a reinjection fence immediately downgradient. Alternative Y: Mr. Hoda stated that alternative Y relies on the process of monitored natural attenuation. *See attached Alternative Z: Mr. Hoda stated that alternative Z, also known as the No Action Alternative, involves leaving the site in its present condition without any remediation system installed. Mr. Hoda stated that the handout includes more detailed explanations of each alternative. *See attached. Estimated Mass Removal Versus Time: Mr. Hoda displayed a graph showing the mass removal versus operating time. Mr. Hoda stated that alternative A achieves the highest percentage of mass removal, 94 percent. *See attached. Squeteague Harbor: Mr. Hoda stated that a concern was raised in regard to contaminants in Squeteague Harbor. He stated that there evaluations found that in the area of the harbor the contaminants were about 140 - 150 feet below the ground surface, therefor there is no exposure potential for people. Mr. Hoda added that on the southern lobe the contamination has started coming up. Mr. Hoda stated that they sampled five locations and the data was collected on September 23, 1997. He stated that they did not find any base related contaminantss. Mr. Hoda stated that they only found low levels of chloroform. Mr. Hoda displayed a map of the five locations that were sampled, two locations were from springs, and three locations were beach areas. Mr. Hoda stated that a presentation was made to the Joint Process Action Team (JPAT) on September 30, 1997. He stated that the JPAT preferred an extraction system east of Route 28, making sure that they include an in-plume treatment system. Mr. Sobel added that there was some diversity amongst the JPAT members, and one member was in favor of natural attenuation. Mr. Hoda stated that the JPAT did not want a system west of Route 28 and summarized that the JPATs recommendation was a modified alternative E. Mr. Hoda explained that the "modified" E alternative included:
Mr. Keene asked what the cost effectiveness was for this alternative. Mr. Miller stated that this alternative cost more than alternative E but less than alternative C. He added that due to the newness of this alternative they assumed the cost to be between $107.8 million and $83.9 million. Mr. Keene asked what the cost would be after 100 years. Mr. Hoda stated that you would multiply the annual figure by 100 to determine that figure. Mr. Snyder added that a lot has to be based on observational behavior of the system. He stated that they estimate twenty years down the road, and different types of modeling is done to get more accurate predictions of contaminant concentrations over the years. He added that they are fairly simple projections, and most of the alternatives taper off between twenty and fifty years. Mr. Keene stated that the machines would still be running. Mr. Snyder concurred however they will be doing five year reviews for the life of they systems. He stated that if at some time during the twenty year plus time frame they do not see anymore benefit, they will make a decision to cut them back or shut them off. Mr. Keene stated that this was the equivalent to starting a system in 1897 and the process being completed now. Questions and Answers: Mr. McGreery a resident of Cataumet, asked if in fact the level going to Squeteague Harbor was closer to the groundwater. Mr. Snyder concurred. Mr. McGreery then asked if the contaminant level in that area was as serious as the area going toward Red Brook Harbor. Mr. Snyder stated that it was relatively the same. Mr. McGreery stated that they were not addressing a fence line in this area. Mr. Hoda stated that alternatives A and B address that area. Mr. York asked if they received the results from the samples taken from Red Brook Harbor. Mr. Hoda replied that he did not have those results as they are still in the process of being validated. Mr. Hoda stated that he would get the data to Mr. York as soon as he receives it. Mr. York asked how long it would be until the data was available. Mr. Hoda stated that it would probably be a couple of weeks. Mr. York asked in regard to the costs, why alternative Y and alternative Z had costs of $8 million and $1.4 million respectfully. Mr. Marchessault replied that natural attenuation includes monitoring of the system. He added that under the No Action alternative involves less monitoring however, some monitoring. Mr. Marchessault stated that the cost over the twenty year time period is mainly a monitoring cost. Ms. Wojner asked if they would be testing the wells to determine the leading edge of the southern lobe, before the November 3, 1997 decision date. She also asked if there were any hot spots that they do not know about yet. Mr. Miller stated that there was one other well they could sample near Squeteague Harbor, that they did not sample. He stated that they could look at that, adding that the end of the public comment period is October 10, 1997. Mr. Miller stated that he did not believe they could get the well sampled and have results available before the end of the comment period. Mr. York asked if they could have the results before the end of the decision period. Mr. Forden, from Jacobs Engineering stated that the data gap work that was referred to was essentially designed to assure they knew enough to avoid fatal flaws. In all of the conceptual designs, particularly C, D, and E, some portion of the plume would be allowed to naturally attenuate. Any portion of the plume that is allowed to naturally attenuate would require further investigation modeling and predictive modeling, as well as follow-up modeling. Mr. Forden stated that as they move into the detailed and final design effort, there will be additional drilling, sampling, and modeling work to be done. Ms. Wojner asked if there would be a regular schedule of monitoring the wells during the design process. She asked if they would be reassured that the contaminants in the part of the plume that will be discharging into Squeteague Harbor is something that they do not need to be concerned about. Mr. Snyder stated that a natural attenuation program would be set up, and reviewed by the agencies to assure that they are monitoring appropriately. He stated that they would install new wells and establish frequency. Mr. Snyder stated that there would be a regular review of the data generated, and the work would be sampled twice a year. He stated that the regular report, or trend analysis, would assure that the projections are being followed. Mr. York asked if the monitoring program would be part of the document being released in December. Mr. Snyder stated that the detailed execution plan would lay out a detailed network and modeling frequency. He stated that they will do monitoring to support that plan. Mr. Snyder stated that the execution plan would lay-out different pieces of the projects, will describe them, and will include the schedule for conducting the projects. Mr. Marchessault added that once the final configuration is laid out, AFCEE is required to submit a performance monitoring evaluation plan to the US EPA and that would indicate all the wells that may have to be installed or monitored, and at what frequency. A member of the audience stated that one of the most expensive alternatives cost $124 million, and asked why the town could not spend $4 million on alternative Z and $120 to provide everyone with town water and a sewage system. Mr. Snyder replied that in the last year, AFCEE has paid for several public water connections in Falmouth and Mashpee, as well as replacing damaged wells. He stated that the conversion of an entire town from well water to town water is not in AFCEE’s purview. Mr. Snyder stated that AFCEE’s task within this superfund program is to deal with the site itself. Mr. Dimmick stated that the goal is to have less than 5 ppb of VOC’s and asked if the leading edge of the plume is at 20 ppb. Mr. Snyder stated that the leading edge of the plume is at 5 ppb. Mr. Dimmick asked what was in the leading edge of the plume. Mr. Snyder stated that the darker areas identified on the map were areas of 20 ppb or above. Mr. Dimmick stated that he was trying to understand if he has 3 ppb and the goal is 5 ppb, and 75 percent or better of the particles are removed, the water would be at a drinkable level, which would indicate that anything at 75 percent or better is perfection. He asked why they cared if it was at 90 - 92 percent. Mr. Hoda stated that the 90 percent of the 75 percent that he mentioned is the total of the total mass. It refers to if they reduce 75 percent of the entire area of the plume. Mr. Snyder added that a lot of this involves waiting for the plume to get to the fences. He stated that if the ETR fence along Route 28 is turned on, and in twenty years 75 percent is captured, it does not mean that the entire plume is reduced 75 percent, it means that 75 percent of the plume has come through the fence. Mr. Snyder stated that it is not an even reduction throughout the body of the plume. Mr. Dimmick asked if the plume is 75 percent, over the ten years does the plume tend to naturally attenuate anyway. Mr. Snyder stated that it may be. He stated that a lot of the unknowns in terms of attenuation is exactly how these plumes will behave. Mr. Snyder stated that rough estimates show that it would take two to three flushes to reach those levels. Mr. Snyder stated that this was revolving around stopping further migration. Mr. Sobel stated that there were a number of different matrices concerned with how they are going to clean up the plumes. He stated that not everyone has the same objective or goal. Mr. Sobel stated that some of the "stake holders" are satisfied with safe drinking levels, and there are others who want the goal to be returning the water to the state it was at before there was any contamination. Mr. Sobel stated that there are different goals that people want to achieve. Mr. Coggeshall stated that the Board of Selectmen (BOS) had a similar presentation at one of their meetings. He noted that the BOS voted to support alternative E or some variation of that, with the emphasis being that there would be no intrusive action in the Cataumet Village area. He stated that whether it be alternative E or alternative E with modifications, the BOS recommended that the action take place east of Route 28, the goal being keeping the community not involved with trying to get some of the remediation efforts close to the water line. Mr. McGreery asked why the worst area is not addressed on all the alternatives. Mr. Hoda stated that the plume will eventually migrate anyway, so one option was to include waiting for the plume to travel to the downgradient system. Mr. Snyder added that this could tell the difference between what benefit in performance time it gives. Mr. McGreery stated that the evaluation criteria listings for alternative A, B, D, and E, were all equal. Mr. Snyder asked what threshold he was referring to. Mr. McGreery asked if they were equal, and the alternatives A, B, and D seem to be overkill when alternative E will do the job, why are they considering the other alternatives. Mr. Snyder stated that the threshold criteria is the first part of the consumer reports. The real differentiating factors come into play in the rest of the questions that are asked. Mr. Snyder stated that questions concerning whether any other habitats are being damaged, socioeconomic impacts from construction, and other related questions are answered, however this is just the first few criteria. Ms. Wojner stated that it was her understanding that the land fill was not totally capped, and asked what portion was not capped. She stated there are 60 acres of land fill, and asked how it was that there are only 52 gallons contained in a two mile plume. Mr. Marchessault stated that there are 60 acres of capped land fill, and 40 acres of land fill which are currently uncapped. Mr. Marchessault displayed a map of the land fill area. He stated that the three cells of uncapped area go back to operations from the 1940’s and 1950’s. Mr. Marchessault stated that they are currently evaluating whether there is any contamination coming from the three cells, and whether there is any need for action to be taken. Mr. Snyder stated that a lot of the contaminants put into the land fill could have been released at the surface and fuels degrade through time. He added that although it is not likely, it could have been one drum of contaminants. Mr. Miller stated that the land fill operated for 40 to 50 years. Mr. Snyder noted that the input of organic compounds into the land fill could have been sporadic. Mr. Snyder stated that this was the main land fill, and all the sanitation and construction debris was dumped there as well. Ms. Wojner asked if the monitoring plan included the marine environment. Mr. Snyder stated that they will monitor some of the marine life pre-construction, in their ecological monitoring program to determine a baseline. He stated that they would continue to monitor until they realize that there is no impact to the marine environment, including post operation sampling. Mr. Hoda stated that the state is doing some shellfish evaluations as well. Mr. Locke asked if the public realized how much pollution goes into Red Brook Harbor, Squeteague Harbor, and Buzzards Bay, every time they turn on their outboard motor or diesel engine. He stated that the public is pressing to have this plume captured, when the amount of pollution in Red Brook Harbor is insignificant relative to the recreational boat use that occurs every day in the summer. Mr. Locke stated that it would benefit the public to do testing on the amount of contamination recreational boat use contributes to the harbors in relation to the amount of contamination from the plume. Mr. Snyder stated that in the document they talk about the levels that are required to be a surface water concern. He referred to page seventeen of the document stating that for TCE the ambient surface water quality criterion for damage to surface water habitats is 21,900 ppb. Mr. Snyder stated that the highest levels of TCE they have found are around 17 ppb. Mr. Locke stated that it would be beneficial if Mr. Whitaker spent some time letting the public know about those figures. Mr. York replied in response to Mr. Snyder’s statement that they could not get involved in paying for the town to do things with their water supply and sewer system, that there is presently $8 million on the table to the Town of Falmouth for those sorts of purposes. Mr. York stated that there is a precedent, and this did happen for another plume. Mr. Snyder stated that there may be some sewer improvements for this part of Falmouth. He clarified that they had inorganics from the sewer treatment plant in that other plume, which is different from this plume. Mr. Snyder stated that instead of treating the plume and sewer treatment plant, they did an off-set program. Mr. Sobel asked if Mr. Snyder was referring to the Ashumet Valley plume. Mr. Snyder concurred that he was. Mr. Sobel stated that a response would be provided for each comment submitted. He convened the meeting at 8:50 P.M.
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