Coonamessett River Cranberry Bog Meeting Minutes
Mr. Karson, a community involvement specialist for the Air Force Center for Environmental Excellence (AFCEE), convened the meeting at 6:05 p.m. He stated that the purpose of tonight’s meeting is to provide an update on the Air Force’s Coonamessett River project. Mr. Karson introduced Mr. Minior, the Deputy Program Manager for AFCEE, Mr. Lim from the United States Environmental Protection Agency (EPA), and Mr. Pinaud from the Massachusetts Department of Environmental Protection (DEP). He noted that copies of Mr. Minior’s presentation slides are available. He then reviewed the agenda and meeting groundrules. Mr. Karson stated that a summary is being recorded of tonight’s meeting, and it will be posted on the Massachusetts Military Reservation (MMR) Web site. Agenda Item #2. Coonamessett River Treatment System Update Mr. Minior displayed a map of the Fuel Spill 28 (FS-28) plume of contamination that emanates from the base, travels through Lochstead Estates and into the Coonamessett bog area. He then pointed to the Coonamessett River. Mr. Minior displayed another map and pointed to the Coonamessett bog area located near Hatchville Road, the treatment plant, the extraction well, and the shallow well points. He noted that the numbers with letters and circles on the map represent surface water sampling locations. He also noted that the last few pages of the handout include the surface water sampling results. Mr. Minior reported that since the startup of the Coonamessett River system in April 1999, surface water samples have been taken on a monthly basis. He stated that before the system was turned on, there were detections in the surface water in this area. Since that time, the surface water in the river has reached non-detect for ethylene dibromide (EDB). Mr. Minior reiterated that the river surface water has been non-detect for EDB since system startup in April 1999. Consequently, in September/October 1999 Ocean Spray conditionally indicated that, as long as the system continues operating and the surface water remains non-detect for EDB, it will bring those cranberries back into the cooperative the following growing season, which currently is about to begin. Mr. Minior stated that if the surface water remains non-detect, the cranberries will be harvested this fall and will go back into the cranberry system. Mr. Minior reported that the Air Force, working with the Falmouth Conservation Commission, has agreed to install a new fish ladder at the outlet of Pond 14. He noted that this installation has not yet occurred. Mr. Minior displayed a map and pointed to Pond 14, Flax Pond, and the existing fish ladder that will be replaced. Mr. Minior displayed a photograph and pointed to the FS-28 treatment plant, some of the bog network, and the Coonamessett River. He then displayed a photograph of the shallow well point system and explained that the pipes go down approximately 15 feet into the ground and are used to extract the shallow groundwater. He further explained that the intent of the shallow well point system is to intercept the EDB below surface and extract it before it reaches the surface. Mr. Minior displayed a photograph of the Adams bog. He noted that some of the cranberry bogs are separated from the river using earthen berms; the Adams bog, however, is separated from the river using a vinyl sheet pile wall that was driven 15 feet into the ground. Mr. Minior also displayed a photograph of the LaSalle bogs, which are smaller bogs. He noted that normally berms are approximately 24-feet wide at the base; in this case, installing the vinyl sheet pile wall saved bog acreage. A member of the audience asked if the decision to install the vinyl sheet pile wall was made on the assumption that the chemicals will surface only in the Coonamessett River itself. He questioned how the vinyl sheet pile wall separates the river from the bog. Mr. Minior explained that the vinyl sheet pile wall separates the river from the cranberry bog such that, if the river level were to rise, it would not flood back into the cranberry bogs. He stated that if in fact there were EDB in the river water, it would not be able to enter the bog if the water levels rose. Mr. Minior displayed a photograph of the Pond 14 outflow. He reported that a fish ladder would be installed in this area to replace the existing structure. He then displayed a photograph of the berm located south of Thomas B. Landers Road. He pointed out on the photograph the location of the berm that was constructed, which raises the level approximately three feet to separate the bog from the river, thereby preventing the river from entering the bog area. Mr. Minior displayed a conceptual image of the FS-28 plume as it migrates with the flow of groundwater from the base and travels beneath Coonamessett Pond. He noted that the FS-28 plume travels beneath the western arm of Coonamessett Pond and is pulled up by the Coonamessett River. He pointed to the location of an extraction well that was installed in an attempt to intercept the plume and prevent it from traveling down river. He stated that the extraction well extracts approximately 400 gallons per minute (gpm) of water, which is about 500,000 gallons per day (gpd). A member of the audience asked Mr. Minior to explain how the plume is being intercepted. Mr. Minior replied that an extraction well, which is installed in the ground, pumps out approximately 400 gpm of water. The water is sent to the FS-28 treatment plant where it is run through carbon filters, and then it is reinjected back into the river. He explained that the intent is to cut off the plume with extraction well 5 (EW-5) and the shallow well points in order to remove the contamination before it is released into the Coonamessett River. He noted that although the plume will be intercepted, over time it will flush itself out. Mr. Minior reported that the "wedge" of EDB that is separate from the main body of the plume is being monitored on a quarterly basis. He reported that recently, another well located farther south, which had been non-detect for EDB, actually had a detection in it. Consequently, that well is being sampled on a monthly basis for the next few months in order to understand what is taking place. Mr. Minior reported that the surface water samples south of that point still are non-detect, regardless of that detection. Mr. Minior stated that it could be that the wedge of the EDB plume simply is moving through. Mr. Minior displayed a close-up graphic of the FS-28 plume leading edge and pointed out the well with the EDB detection. He noted that the sampling results are available in the last pages of the handout. He referred to the 1300 series, A and B, sampling results. He pointed on the map to the sampling locations where EDB detections were seen previously. He then pointed to sampling location 1306, where EDB was detected, and noted that this sampling point is located just outside the edge of the FS-28 plume. Mr. Minior stated that sampling location 1306 always had been non-detect, as indicated by the sampling results. Location 1306 has been re-sampled and results are expected soon. A member of the audience asked how the extracted water is reinjected. Mr. Minior pointed out the location of the bubbler, which he described as a piece of corrugated pipe with water cascading out of it. Mr. Minior stated that the two purposes of the bubbler are to reinject the water into the river and to oxygenate the water as it cascades down, thereby raising the oxygen level, which is better for the fish. Mr. Minior stated that the sampling plan for the leading edge of the FS-28 plume has been modified to include more frequent sampling of the downgradient wells. He reported that since January 2000, the shallow well system influent, the extraction well influent, and the surface water locations have been tested. Mr. Minior also noted that AFCEE wanted to determine if cranberry plants could take up EDB, and so Kansas State University (KSU) currently is growing cranberry plants that were collected in this area. The plan is to harvest the plants in mid October 2000 and analyze them to make that determination. The KSU report is due in November 2001. Agenda Item #3. Discussion Ms. Dupee inquired about the status of the FS-28 plume and how far it has advanced. Mr. Minior referred to the second presentation slide, which is a depiction of the plume location. He said that there have been discussions about the Southwest Operable Unit (SWOU), which has a Phase 1 and a Phase 2. The FS-28 and FS-29 plumes were discussed at a recent meeting, and currently the final record of decision (ROD) is being developed. The ROD describes how the FS-28 plume will be cleaned up. Mr. Minior stated that although the recommended remedy for FS-28 has not yet been determined, it will include the existing extraction well 1 (EW-1) and the shallow well point system. Ms. Dupee asked if the depiction on the map is the FS-28 plume’s current configuration. Mr. Minior replied that this is what the plume looks like. He referred to the three-dimensional cross section and pointed out that, for the most part, the plume is well over 100 feet below ground surface. He noted that only when the plume reaches the vicinity of the shallow well points is it actually right below the surface, and it would be upwelling there if it were not being intercepted. Mr. Karson added that the FS-28/29 public comment period is open until April 25, 2000. He also noted that the majority of the EDB mass is located south of the western arm of the Coonamessett Pond, where there are the higher EDB concentrations in the groundwater. He stated that the FS-28 plume north of that western arm is dilute in nature. Mr. Minior referred to the map and pointed out an area of the plume from the western arm of the Coonamessett Pond, south, that contains approximately 22 pounds of EDB. He also noted that in the year that the EW-1 has been operating in conjunction with the shallow well points, almost six pounds of contamination have been removed. Mr. Dupee asked if the Falmouth water supply well, which is located near the western arm of the Coonamessett Pond, is drawing up a large amount of water, thereby causing the plume to concentrate in that area. Mr. Minior replied that this scenario has been modeled at the current rate of operation, which is approximately 700 gpm for the Coonamessett water supply well. He stated that the water supply well is not affecting the plume because there is an 80-foot separation between the top of the plume and the well screen. Mr. Minior stated that AFCEE, in conjunction with the Town of Falmouth, is conducting monthly sampling in order to ensure that nothing from the well is entering the town water supply. As an additional safety measure, a carbon treatment system has been added. Mr. Minior noted that to date, no contaminants have been detected entering or exiting the treatment system. Mr. Dupee inquired about the disposal of material extracted from the water. Mr. Minior replied that the carbon removes the contamination, and since startup of the treatment plant, the carbon has not needed to be changed. However, today there was a detection and a carbon change-out will be ordered and completed within the next couple of weeks. Mr. Minior explained that there are two 20,000-pound carbon canisters, between which sampling is conducted in order to ensure that the lag vessel will always put out clean water. He stated that when there is a detection between carbon canisters a carbon change-out is ordered. Mr. Minior noted that the company that provides the fresh carbon removes the used carbon and regenerates it at the company’s facility. Mr. Dupee commented that his question was not answered. He again asked about the disposal location of the extracted EDB. Mr. Minior replied that the company that provides the carbon, in this case Calgon, extracts the EDB and is responsible for its disposal. He noted that Calgon disposes of the EDB under a regulated process. Mr. Karson added that it is his understanding that Calgon recycles the carbon. He also noted that recycled carbon is not used here at Otis Air National Guard base; rather, virgin carbon always is used. Mr. Karson stated that there are a variety of methods to remove the contamination from the carbon. He further explained that heat can be used to burn off the carbon, or the EDB can be precipitated off. Mr. Karson said that he does not know what process Calgon uses to remove the contaminant from the carbon, but it does recycle and reuse the carbon, according to whatever laws are required for proper disposal and handling of that waste. Ms. Dupee asked if Mr. Karson is referring to the EDB. Mr. Karson replied that he is. Ms. Dupee inquired about the fate of the EDB. Mr. Karson replied that it is up to the company, in this case Calgon, which has a contract for recycling the material based on the standards that are set in that particular state. Mr. Dupee asked when the FS-28 plume would be cleaned up. Mr. Minior replied that, depending on the final remedy, the plume should be cleaned up in nine to eighteen years. He stated that if the existing setup were used, it would take 18 years to clean up the plume. If additional wells were installed farther up in the plume, it would take approximately nine years. Mr. Minior stated that the possible remedies for FS-28 and FS-29 plumes have been discussed tonight, and the CS-20 and CS-21 ROD is signed and those systems will be build in about a year and a half. He stated that, with the exception of the FS-1 plume in Mashpee, which is coming out in another cranberry bog area near Johns Pond, those are the last treatment systems right now that AFCEE intends to build, given the available information about the groundwater. Mr. Dupee asked if it is correct that no additional plumes are expected to be heading toward Coonamessett Pond. Mr. Minior replied that this is correct, based on current information. Mr. Jewett inquired about chemicals other than EDB that are of concern in this area. He noted that he recalls that a number of chemicals were detected when wells in this area were being tested. Mr. Minior replied that in terms of the FS-28 plume, the contaminant of concern strictly is EDB. He referred to the maps that show some of the chemical spill plumes, CS-20/21, and noted that those contaminants are chlorinated solvents. Mr. Minior explained that carbon treatment works well on any of those constituents, including chlorinated solvents and fuel-related constituents such as toluene or benzene. Ms. Dupee commented that it is his understanding that there are many "trace kinds of things" that are of concern in terms of the water supplies. He said that he is concerned about trace detections in the town water supply well. Mr. Minior replied that AFCEE is not aware of anything else right now. He stated that once the carbon system is installed, it will remove virtually everything that comes through it. Mr. Karson added that this information is based on approximately 40 groundwater monitoring wells installed south of the western arm of Coonamessett Pond, and another 30 groundwater monitoring wells installed north of that area. He stated that there is a large network of test wells, which were sampled every ten feet during their installation. He noted that follow-on sampling also has been done for a variety of compounds, including solvents and fuels, not just EDB. Mr. Karson stated that there is a lot of good data to support Mr. Minior’s conclusion. Ms. Dupee asked if carbon filtration and extraction wells have ever been used before. Mr. Minior replied that currently at least six plumes are being cleaned up with carbon and various extraction well networks. Ms. Dupee asked if Mr. Minior is referring to just Cape Cod or elsewhere. Mr. Minior replied that he is referring just to MMR. He added that carbon pump and treat, also referred to as extraction, treatment and the reinjection (ETR), is one of the technologies that is used most often for groundwater cleanup. Mr. Karson added that more than ten million gallons of groundwater a day are being pumped and treated. He stated that when the additional systems that Mr. Minior mentioned are constructed, the amount of groundwater being pumped and treated will increase to almost 18 million gallons a day. The cleanup program is beyond the 50% point for installing the groundwater treatment systems. Eventually the program will entail just operating and maintaining the systems, and fine-tuning them in order to maximize their efficiency over the many years that some will need to operate. Mr. Minior added that the CS-10 south/southwest system, and the modification of the CS-10 In-Plume system, will be turned on by the end of April, which will result in an additional couple of million gallons per day. Ms. Dupee asked if the funding for this project would remain in place if there were a change in the administration. Mr. Minior replied that as long as the government is either Republican or Democratic, he does not anticipate any funding problems for this national program. He stated that AFCEE receives its funding from the Department of Defense (DoD) for environmental restoration, and he does not anticipate that Congress would not put money against that, regardless of which administration is in place. Ms. Dupee questioned whether MMR is a Superfund site. Mr. Minior replied that it is a Superfund site, and it is the DoD’s responsibility to address it. Ms. Dupee asked if the funding comes out of the defense budget. Mr. Minior replied that it does – it is one of the DoD’s appropriations. Mr. Karson stated that the DoD has made a commitment to make the MMR Superfund cleanup its number-one priority. He reported that, unlike any other Air Force cleanup program in this country, AFCEE has received full funding for this project. He commented that since the Air Force has taken over the cleanup program, it has provided whatever is necessary, and this should continue. Agenda Item #4. Adjourn Mr. Karson adjourned the meeting at 6:37 p.m.
|
