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Impact Area Review Team Meeting Minutes
Action Items:
Future Agenda Items:
Handouts Distributed at Meeting:
Agenda Item #1. Welcome, Review Agenda, Approval of April 27, 2004 IART Minutes Mr. Murphy convened the meeting at 6:05 p.m. and the Impact Area Review Team (IART) members introduced themselves. Mr. Murphy then reviewed the agenda and asked if there were any changes to the April 27, 2004 IART meeting minutes. No changes were offered and the minutes were approved as written. Agenda Item #2. Late-Breaking News and Responses to Action Items from the 4/27/04 IART Meeting Mr. Gregson stated that last week he notified the team of a perchlorate detection in a private well east of the Massachusetts Military Reservation (MMR), and would be discussing that detection later as part of the "Investigations Update." Mr. Murphy noted that by the end of the month the U.S. Environmental Protection Agency (EPA) plans to send IART membership recruitment letters to approximately 300 Sandwich residents who live outside the eastern boundary of the base. He also noted that he has received one membership application from a Sandwich resident, but hasn't yet had the chance to review it. Ms. Adams asked whether the modified well cost table was distributed to the IART. Mr. Gregson replied that the original well cost table provided to Mr. Schlesinger was distributed to all team members; however, the modified well cost table should be completed in about a week, after which it too will be distributed to all IART members. Mr. Cambareri inquired about sampling of the Upper Cape Water Cooperative (the Co-op) sentry wells. Mr. Gregson replied that in response Todd Borci's request, the IAGWSP sampled the shallow screens at sentry wells C4 and C7, both of which tested nondetect for perchlorate and explosives. He noted that the IAGWSP has also asked for the Co-op's permission to sample the sentry wells using a packer in order to isolate intervals within the 30-foot well screens there, but has not yet received a response from the Co-op. Mr. Cambareri inquired about alternatives, should the Co-op not allow the IAGWSP to conduct packer sampling. Mr. Gregson replied that the IAGWSP would determine the data gap that situation creates and look at existing and future wells to cover those data needs. Mr. Cambareri said that he hopes for resolution among the parties - the IAGWSP, EPA, and both DEP's Bureau of Waste Site Cleanup and its Water Supply branch - so that the appropriate type of monitoring can be done. Ms. Conron mentioned a recent article in the Bourne Enterprise, which, she said, noted that Co-op officials would be looking to the IAGWSP to pay for an engineer. Mr. Gonser said that the IAGWSP shares its data with the Co-op, which, to his knowledge, has not yet made any request for further support. He also noted, however, that it was recommended that an IAGWSP representative attend the next Co-op meeting, which might be an opportunity for the Co-op to bring up that issue. Mr. Gonser further noted that at the Co-op's last meeting, Dave Hill of the IAGWSP gave a full briefing on the investigation at the J Ranges. He also said that IAGWSP and Co-op staff members talk every couple of days. Agenda Item #3. Remediation Update J-3 Range Soil Rapid Response Actions Mr. Gregson stated that the J-3 Range Rapid Response Actions (RRAs) for soil were designed to remove some of the identified or suspected source areas, but are not anticipated to be the final soil remedies for these sites. The contaminants of concern (COCs) at the J-3 Range are perchlorate and explosives. Mr. Gregson reminded the group that the J-3 Range RRAs for soil were designed to be flexible, and have in fact changed since initially introduced. He noted that the original plans focused on three areas in the center of the J-3 Range (the detonation pit and burn area, the former burn box, and the area north of the target), and involved the removal of approximately 690 tons of soil. The revised plans, however, include removal of an additional 1,500 tons of soil, bringing the total removal amount to about 2,200 tons. The additional soil removal sites include areas around the former melt/pour building, a former Minuteman test area, expanded areas at the target walls, and potential source areas to the south. Mr. Gregson noted that the melt/pour building has been taken down and Textron conducted extensive sampling at the site, where quite a bit of soil removal work is going to be done. Mr. Gregson also mentioned that changes to the J-2 Range RRA plan are still under development, and will be presented to the team at a later date. He then noted that the J-3 Range groundwater RRA plan, which involves using components of the Installation Restoration Program's (IRP's) Fuel Spill 12 (FS-12) treatment plant, will be discussed at the June IART meeting. Ms. Adams questioned whether the J-3 Range RRA plan for soil underwent a public comment period. Mr. Gregson confirmed that the plan underwent an informal public comment period at the time it was issued. Demo Area 1 Rapid Response Actions Mr. Gregson reported that the one-foot excavation area at the Demolition Area 1 (Demo 1) site has been completed and closure sampling results there are all nondetect. Unexploded ordnance (UXO) clearance and soil removal is ongoing at the center of the depression, where the depth of excavation is expected to be anywhere from a couple of feet to as many as 16 feet, until undisturbed soil is reached. Mr. Gregson noted that the excavation work should be completed by the first week in July, and thermal treatment of the excavated soil should begin shortly thereafter. Mr. Gregson also referred to the Demo 1 RRA for groundwater and reported that the piping and utility work that can be completed prior to the arrival of the modular treatment units is almost finished. The extraction and injections wells have been completed, and the modular treatment units are in the process of being fabricated and will be delivered in the middle of the summer. The anticipated startup date for both the Pew Road and the Frank Perkins Road systems is September 2004. Demo Area 1 Revised Draft Feasibility Study Mr. Gregson reported that on May 20, 2004, the IAGWSP submitted the revised draft Demo 1 Feasibility Study (FS) document to the regulators and the IART for review. He noted that the document presents cleanup alternatives for Demo 1 groundwater, including a background alternative, a baseline alternative, a no-action alternative, a 10-year cleanup alternative, and an alternative that cleans up to risk-based standards. The document also presents information on how each alternative compares to the selection criteria. Mr. Gregson noted that the Demo 1 FS document is available on the IAGWSP website and at the local libraries, and will go undergo an informal public comment beginning June 22, 2004, the date of the next IART meeting. Mr. Gregson said that the current scheduled timeframe from submittal of the draft FS to a final cleanup decision is about 14 months. However, the IAGWSP has been working with the regulators to decrease that timeframe, and he expects that by the next IART meeting he'll be able to inform the team about a shortened timeframe. Ms. Adams inquired about a groundwater discharge permit relating to Demo 1. Mr. Gonser said that in response to a letter from the IAGWSP to the state, DEP basically indicated that if there was compliance with appropriate portions of the Massachusetts Contingency Plan, the groundwater discharge would be considered effectively regulated. The IAGWSP had replied that it would comply with those sections of the MCP that DEP specifically pointed out. Mr. Pinaud noted that DEP recently received that letter, which also noted that the IAGWSP would be submitting documents that outline specific procedures, which DEP will review. If DEP finds these acceptable, the IAGWSP can discharge the treated water from the Demo 1 system. Ms. Adams suggested that this would be similar to what would be contained in a permit. Mr. Pinaud agreed. Agenda Item #4. Investigation Update Northwest Corner Investigation Update Mr. Gregson stated that the effort is proceeding to connect to town water the three homes with private wells in the Northwest Corner investigation area. He also noted that the most recent sampling round showed a perchlorate detection at 0.65 parts per billion (ppb) in well RSNW01. Mr. Gregson added that a number of wells are yet to be drilled at the Northwest Corner in order to continue the investigation of the perchlorate plume and the 5-ppb RDX detection at monitoring well 323 (MW-323). Ms. Dolan inquired about the schedule for the town water hookups. Mr. Gregson replied that the right-of-entry agreements have been drafted and will be sent out to the homeowners soon. Also, the U.S. Army Corps of Engineers is getting the paperwork in place with the subcontractor that will do the actual work. He said that it should take about four to six weeks to complete the preliminary work and get those homes hooked up to town water. Mr. Pinaud asked if each of the homeowners responded to the IAGWSP's offer to provide town water hookups. Mr. Gregson replied that he doesn't think a response has come in yet from the homeowner with the private well designated RSNW02. Mr. Dow inquired about drilling wells to determine the source areas associated with the deeper detections of perchlorate and RDX. Mr. Gregson noted that some deep detections of RDX and perchlorate would track back to the base, and the deeper RDX detection would track back to the Central Impact Area. He said that an upgradient well will be installed as part of the Northwest Corner investigation and a couple of wells will be installed "at the other end" as part of the Central Impact Area investigation to see if there's a connection between the two areas of contamination. Mr. Dow concluded that the IAGWSP would be installing wells "to define it from both ends." Mr. Gregson agreed. Mr. Mullennix asked if the IAGWSP's response to EPA and DEP comments on the Northwest Corner data summary report is forthcoming. Mr. Gregson replied that a couple of weeks ago the IAGWSP submitted a response to EPA's comments, and the response to DEP's comments is expected to be submitted soon. Mr. Mullennix also inquired about the status of the air dispersion modeling effort. Mr. Gregson replied that the IAGWSP has been working with the Army Center for Health Promotion and Preventive Medicine (CHPPM), which seems to have an appropriate model, and is looking at the data required to plug into the model, and whether additional work would need to be done, such as more studies on the emissions of fireworks. Mr. Mullennix mentioned the importance of ensuring that both EPA and DEP approve of the air dispersion model that's used, so that there's concurrence by all parties on the results. Mr. Gregson noted that he was just informed that the homeowner with private well RSNW02 had in fact accepted the IAGWSP's offer to provide a town water hookup. Mr. Mullennix asked who would be responsible for paying the water bills associated with the new hookups. Mr. Gregson replied that the homeowners would. Mr. Cambareri referred to what he called the "very narrow area" that's evolved to be called the Northwest Corner investigation area, and said that he's curious to know whether the areas to the south and north are clean or contaminated. He mentioned the area toward the rotary and said that he thinks it would be prudent to determine if there's "a connection between what's coming off the Central Impact Area and this particular sector here," which is undeveloped and in the past was identified by the U.S. Geological Survey (USGS) as suitable for public water supply. Mr. Cambareri said that when the IART originally called for investigation of the northwest quadrant, the concern was for a larger area than is currently being investigated. Mr. Gregson said that while that there are no data to indicate that that southern area is contaminated, the Central Impact Area plume is located upgradient, which is important to realize from a water supply development standpoint. Mr. Cambareri agreed and noted that if that southern area is clean and is considered as a future water supply by the community, some type of action ought to be required to halt that plume at the boundary, if it hasn't yet gone past it. Ms. Dolan asked to see a map that shows the relationship between the Central Impact Area plume and the Northwest Corner investigation area. Mr. Gregson displayed such a map and pointed out the Northwest Corner investigation area, some clean wells to the south, and the areas to which the shallower and the deeper RDX detections track back. He suggested that there may be either a connected or discontinuous plume between the Northwest Corner and some of the contamination to the south. Mr. Cambareri asked if there are clean wells upgradient of the area toward the rotary and south of the designated Northwest Corner investigation area. Mr. Gregson mentioned the "95" series wells installed by the Air Force Center for Environmental Excellence (AFCEE), and noted that the IAGWSP also has some nondetect wells there. Mr. Cambareri said that while it's critical to stop the plume that threatens the Co-op's water supply well #2, in his opinion it's also important to consider taking actions to protect that area of clean water in the town of Bourne. Dr. Stahl noted that he had with him the site-wide perchlorate map, in case anyone wanted to look at it during the break. Ms. Conron asked if Mr. Cambareri is suggesting that the area south of the Northwest Corner might be a suitable location for future water supply wells. Mr. Cambareri confirmed that he is, if in fact there's no contamination there. He reiterated that the area was identified by the USGS as a potential water supply location. Ms. Adams referred to the map of the Northwest Corner investigation area and asked if it's correct that wells 94-3, 94-4, and 95-6F were not sampled for perchlorate, as the legend indicates that there are no validated data from them. Mr. Gregson replied that that they may not have been. He explained that in order to avoid duplication of effort associated with similar screen depths, not every well in that vicinity was sampled. Ms. Adams questioned whether having data from those wells might answer some of Mr. Cambareri's concerns. Mr. Cambareri said that while it would depend on the well screens, he thinks it would be beneficial to see what kind of information those wells would provide. He also recommended that in addition to looking at those wells, consideration be given to installing a far-field well in that area to evaluate the off-base situation in terms of whether the water there is clean or has been affected by the Central Impact Area plume. He said that the recent newspaper article about the Upper Cape towns looking for additional water supplies is what brings this recommendation to mind. Western Boundary Recent Results Mr. Gregson stated that the upgradient edge of contamination at the Western Boundary area appears to have been defined by nondetect results for perchlorate in profile samples from MW-316 and MW-317. He also noted that it seems that the source area does not extend back into the Impact Area. Mr. Gregson reported that at MW-308, where profile samples had shown perchlorate detections in four intervals, from 0.5 ppb to 4.1 ppb, the first groundwater sampling round came back nondetect for perchlorate. Also, at MW-269, there was a first-time detection of perchlorate at 0.38 ppb. Mr. Gregson said that based on available data, it seems that there are enough wells to define the extent of contamination in the Western Boundary plume. He also noted that some additional soil sampling is going to be conducted; based on those results, it will be determined whether additional groundwater investigations are required. He said that right now the intention is to submit a draft investigation report on the Western Boundary area in September. Mr. Cambareri noted that according to the map's legend, the groundwater contours shown are based on a model identified as MMR-10. He said that in previous maps he'd noticed a "major deflection" along the 18-foot contour line around a small kettle-hole pond, and is pleased to see that the MMR-10 model does not reflect such a major deflection from "that tiny surface water." J-1 Range Recent Unvalidated Detections Mr. Gregson reported that at the J-1 Range plume, which originates from the J-1 interberm area and migrates to the northwest, perchlorate was detected at 21 ppb and RDX was detected up to about 3.5 ppb in profile results from MW-326, which was drilled along the edge of the plume. A low level of 2,6-DNT was also detected there. Groundwater results from MW-303, to the south, closer to the suspected source area, showed perchlorate at 31 ppb in the deeper screen and at 2.2 ppb in the shallow screen. A couple of additional wells will be installed downgradient to help define the extent of the plume in that area. Mr. Gregson noted that the J-2 Range Disposal Area 2 plume map has been updated based on validated well data. He reported that groundwater results from MW-292, a flank well near the source area, showed perchlorate at 1.1 ppb in the shallow screen and 0.43 ppb in the deep screen. At MW-293, which is in the middle of the well fence along Wood Road, perchlorate was detected at 44 ppb and RDX was detected at 0.32 ppb. At MW-300, which is also in the middle of the well fence, perchlorate was detected at 51 ppb and RDX was detected at 0.29 ppb. At MW-302, the westernmost well in the fence, perchlorate was detected at 6.9 ppb, and explosives were nondetect. At well MW-305, the easternmost well in the fence, perchlorate was detected at 36 ppb, and explosives were nondetect. Mr. Gregson said that these groundwater results are quite consistent with the profile results. He also noted that sampling of the shallow screens in the Co-op sentry wells C4 and C7 yielded nondetect results for perchlorate. Mr. Gregson further reported that at MW-330, which was drilled downgradient of MW-327 where perchlorate was detected at 1.5 ppb, profile results were nondetect for explosives and perchlorate, which is good news. Also, profile results from MW-331, another flank left of the plume, showed perchlorate at less than 1 ppb. Mr. Gregson said that it seems that that edge of the plume is pretty well defined. Mr. Gregson said that there are a couple of proposed well locations along Gibbs Road. He also noted that well site J2P-39 should help further define the downgradient extent. Mr. Gregson then mentioned that the IAGWSP is working with Natural Resources staff to obtain access to drill in the woods just south of Gibbs Road. Ms. Dolan asked if it's correct that 2,6-DNT was detected with interference at MW-330. Mr. Gregson confirmed that that is correct; 2.6-DNT was seen in profile results. He explained that often there's interference in profiling, but then that particular compound is not verified by the groundwater sample. He noted that a screen was set at that location and a groundwater sample will be collected to confirm the profile result. Mr. Gregson then showed an updated Disposal Area 2 plume map based on profile results and pointed out the well where perchlorate was detected at about 1.5 ppb and the well where it was detected at about 5.5 ppb. Mr. Cambareri asked if it's correct that perchlorate was detected at 5.5 ppb at MW-313. Mr. Gregson confirmed that it is, and added that RDX was detected there at less than 1 ppb. Mr. Dow asked how it's determined whether 2,6-DNT is an artifact of chemical analysis or an explosives breakdown product. Mr. Gregson replied that he doesn't think 2,6-DNT is a breakdown product of RDX. He also said that it might be valuable to provide more information on the history of 2,6-DNT detections in profile samples and nondetects in groundwater samples. Mr. Dow suggested that the 2,6-DNT might be a breakdown product of TNT, which was used prior to the use of RDX. He also mentioned the travel time between the 2,6-DNT detection and the source area. Mr. Gregson explained that DNTs adsorb quite readily onto soil and don't migrate very far, as has been seen at Demo 1. To see such a slow-mover out ahead of a fast- mover like perchlorate, would lead one to believe that it's not a breakdown product. Mr. Dow noted that he's curious about the 2,6-DNT because it's been said that there might be more than one source for the plume. He then asked about the depth at which the 2,6-DNT detection occurred. Mr. Gregson replied that it occurred at 31 feet below the water table (bwt), which is fairly shallow. Mr. Dow suggested that the IAGWSP run a particle backtrack from MW-330 to take a look at a possible source. Mr. Gregson reported that at the J-1 Range plume, which originates from the J-1 interberm area and migrates to the northwest, perchlorate was detected at 21 ppb and RDX was detected up to about 3.5 ppb in profile results from MW-326, which was drilled along the edge of the plume. A low level of 2,6-DNT was also detected there. Groundwater results from MW-303, to the south, closer to the suspected source area, showed perchlorate at 31 ppb in the deeper screen and at 2.2 ppb in the shallow screen. A couple of additional wells will be installed downgradient to help define the extent of the plume in that area. Mr. Gregson noted that the J-2 Range Disposal Area 2 plume map has been updated based on validated well data. He reported that groundwater results from MW-292, a flank well near the source area, showed perchlorate at 1.1 ppb in the shallow screen and 0.43 ppb in the deep screen. At MW-293, which is in the middle of the well fence along Wood Road, perchlorate was detected at 44 ppb and RDX was detected at 0.32 ppb. At MW-300, which is also in the middle of the well fence, perchlorate was detected at 51 ppb and RDX was detected at 0.29 ppb. At MW-302, the westernmost well in the fence, perchlorate was detected at 6.9 ppb, and explosives were nondetect. At well MW-305, the easternmost well in the fence, perchlorate was detected at 36 ppb, and explosives were nondetect. Mr. Gregson said that these groundwater results are quite consistent with the profile results. He also noted that sampling of the shallow screens in the Co-op sentry wells C4 and C7 yielded nondetect results for perchlorate. Mr. Gregson further reported that at MW-330, which was drilled downgradient of MW-327 where perchlorate was detected at 1.5 ppb, profile results were nondetect for explosives and perchlorate, which is good news. Also, profile results from MW-331, another flank left of the plume, showed perchlorate at less than 1 ppb. Mr. Gregson said that it seems that that edge of the plume is pretty well defined. Mr. Gregson said that there are a couple of proposed well locations along Gibbs Road. He also noted that well site J2P-39 should help further define the downgradient extent. Mr. Gregson then mentioned that the IAGWSP is working with Natural Resources staff to obtain access to drill in the woods just south of Gibbs Road. Ms. Dolan asked if it's correct that 2,6-DNT was detected with interference at MW-330. Mr. Gregson confirmed that that is correct; 2.6-DNT was seen in profile results. He explained that often there's interference in profiling, but then that particular compound is not verified by the groundwater sample. He noted that a screen was set at that location and a groundwater sample will be collected to confirm the profile result. Mr. Gregson then showed an updated Disposal Area 2 plume map based on profile results and pointed out the well where perchlorate was detected at about 1.5 ppb and the well where it was detected at about 5.5 ppb. Mr. Cambareri asked if it's correct that perchlorate was detected at 5.5 ppb at MW-313. Mr. Gregson confirmed that it is, and added that RDX was detected there at less than 1 ppb. Mr. Dow asked how it's determined whether 2,6-DNT is an artifact of chemical analysis or an explosives breakdown product. Mr. Gregson replied that he doesn't think 2,6-DNT is a breakdown product of RDX. He also said that it might be valuable to provide more information on the history of 2,6-DNT detections in profile samples and nondetects in groundwater samples. Mr. Dow suggested that the 2,6-DNT might be a breakdown product of TNT, which was used prior to the use of RDX. He also mentioned the travel time between the 2,6-DNT detection and the source area. Mr. Gregson explained that DNTs adsorb quite readily onto soil and don't migrate very far, as has been seen at Demo 1. To see such a slow-mover out ahead of a fast- mover like perchlorate, would lead one to believe that it's not a breakdown product. Mr. Dow noted that he's curious about the 2,6-DNT because it's been said that there might be more than one source for the plume. He then asked about the depth at which the 2,6-DNT detection occurred. Mr. Gregson replied that it occurred at 31 feet below the water table (bwt), which is fairly shallow. Mr. Dow suggested that the IAGWSP run a particle backtrack from MW-330 to take a look at a possible source. Dr. Stahl clarified that 2,6-DNT is not a breakdown product of TNT by microorganisms. He also noted, however, that 2,6-DNT is a propellant and therefore might be found at the base for other reasons. Mr. Mullennix referred to the zones of contribution (ZOCs) for the Co-op water supply wells #1, #2, and #3, and said that it seems that supply well #1 doesn't appear to be in any danger from contamination. Mr. Gregson clarified that, unfortunately, there are perchlorate and RDX detections coming from the eastern end of the J-2 Range, and some particle tracks from those locations head into the ZOC for supply well #1. He also noted that well location J2P-27 is being drilled currently, and it's believed that data from that well will be valuable in terms of determining whether there's any contamination in the upper end of the ZOC for supply well #1. Mr. Mullennix asked about a projected timeframe for contamination to reach supply well #2. Mr. Gregson replied that until the toe of the plume has been identified, it's hard to speculate. He also noted that he's been told that there's a five-year travel time between the sentry wells on Gibbs Road and the water supply well. He added that if the current plume depiction holds up, it would be about five to ten years upgradient of the supply well. Mr. Mullennix then noted that there are some perchlorate detections at the far end of the ZOC for water supply well #3, but there doesn't appear to be any contamination close to the well itself. Mr. Gregson agreed that the available data indicate that the source of that contamination is migrating off to the northwest, while the ZOC runs in a more northerly direction. He also noted, however, that there aren't a lot of data in the center of that ZOC. He added that the IAGWSP is trying to determine that that particular known area of contamination is not affecting the ZOC. Mr. Mullennix asked Mr. Gregson to remind him of the estimated timeframe when the J-1 and J-2 Range source areas originated. Mr. Gregson replied that the J-2 source area is believed to have originated in the 1960s/1970s timeframe, while the J-1 source area is thought to have occurred a little later. He also noted that Disposal Area 2 at the J-2 Range was an open burn/open detonation site, similar to Disposal Area 1. Mr. Mullennix asked if the soil might have been disturbed in some way that exacerbated an additional release. Mr. Gregson replied that he doesn't think so. He also said that the higher level of contamination is a bit beyond the source, which indicates that the source is depleting to some degree. He added that since the activities that occurred 30 or 40 years ago, it's just "taken this long for this plume to develop." Mr. Cambareri said that the nondetects along Gibbs Road provide some comfort that the contamination has not yet reached that area, but he is concerned about the 30-foot screens at sentry wells C4 and C7. He also inquired about the far-field wells associated with water supply well #2. Mr. Gregson replied that the far-field wells are deep enough and have five screens from the water table to bedrock. However, when they were installed profile sampling wasn't being done for perchlorate, only for explosives and volatile organic compounds (VOCs). There were no detections at the time and the screens were spaced evenly through the aquifer. Mr. Gregson said that he couldn't say whether a far-field well, such as MW-63, is screened at an interval that would intercept the perchlorate plume, but it would be important to make that determination. Mr. Gregson then showed a cross-section figure of the plume, pointed out the wells where perchlorate was detected at 5.5 ppb and at 1.5 ppb, and pointed out the screens in the far-field wells and in the sentry wells. Mr. Cambareri noted that the deeper screens in the far-field well appear a little too shallow to be in line with the perchlorate plume. Mr. Gregson said that it's hard to tell whether perchlorate would show up there or go under the screens. He also agreed that if the well were being built today, a screen probably would be set a little farther down. Mr. Cambareri stressed his belief in the importance of being able to sample the sentry wells with packers, as he doesn't think that any information from the 30-foot screens would "bear much significance." He asked that the IAGWSP inform the team of the Co-op's reply to the request to use packers for more discrete sampling of those wells. Mr. Gregson explained that the sentry well screens are wider because the supply well draws water from a relatively thick section of the aquifer, and it's important for the water supplier to have as much coverage through that thickness as possible. In this way, the supplier can get an idea of the water quality in terms of what is coming toward the supply well, over a thicker interval. Mr. Gregson also noted that when the IAGWSP conducts profile sampling, it's essentially collecting a sample for a point in the aquifer, and later steps out to set an average 10-foot well screen. Mr. Cambareri then mentioned that he's aware that the J2P-39 site is located in an area of "unbroken wildlife habitat," and said that he's also concerned about impacts from drilling. He asked what types of innovative designs or protocols the contractors are using in order to reduce the footprint of disturbance from well installations. Mr. Gregson said that a lot of progress has been made. The IAGWSP has coordinated with the base fire department (because welding operations are a fire concern) and worked with the well drillers to minimize the size of the well pad that's needed. Also, impacts are minimized when building many of the roads by flush-cutting the vegetation and putting down geo-textile fabric that's covered with wood chips or fill. In this way the root stock is preserved so that the fabric can be pulled off later and the vegetation can come back. Mr. Cambareri suggested that this might be a worthy topic for a presentation to the IART at a future meeting. He also asked for a comment from Mark Begley, the environmental officer with the Environmental Management Commission (EMC). Mr. Begley noted that the Natural Heritage people at the Department of Fish & Wildlife, and the members of the EMC, are very concerned about taking steps to protect the habitat. He acknowledged that a lot of progress has been made over the past couple years, but also referred to the flush-cutting method and said that not all of the vegetation would come back from the root stock. He said that he thinks there might be additional opportunities to protect the habitat, and there has been continuing discussion about such measures, including minimizing the length of the some of the roads that are constructed. Ms. Dolan referred to the issue of sampling along Gibbs Road and said that she believes it is worthwhile to try to obtain more usable data from the sentry wells for water supply well #2. She also said that the IAGWSP has proposed a couple more well locations along Gibbs Road, but wants to wait for results from the J2P-39 location. She assured Mr. Cambareri that EPA has indicated that additional well locations are needed along Gibbs Road to fully characterize the plume and identify the toe. Mr. Gonser returned to the topic of efforts to minimize impacts from well drilling. He said that the other aspect of that endeavor is to select wells very carefully in order to ensure that wells that aren't needed are not installed and that installed wells provide usable data. He explained that it's a constant tradeoff between ecological impacts versus the data that will be obtained. Mr. Dow inquired about new roads serving as access points for invasive species to move in to forested areas. Mr. Gregson replied that some incidences of that kind have occurred; however, the IAGWSP has a fairly active weed-pulling field crew that removes invasive species trying to establish themselves. Mr. Gonser added that in the past, outside topsoil was brought in to re-vegetate sites, but to help prevent the invasive species problem, now only natural topsoil from the area is used. J-2 Range Eastern Boundary Investigation Mr. Gregson reminded the group that at MW-310 and MW-307 at the eastern end of the J-2 Range, perchlorate was previously detected at concentrations up to 20 ppb. At MW-319, perchlorate was detected at about 5 ppb, and RDX was detected at less than 1 ppb. Mr. Gregson stated that three additional on-base well locations have been scoped, and the IAGWSP is continuing its efforts to find existing off-base wells to sample, as well as off-base locations where additional wells could be drilled to help with the investigation. Mr. Gregson reported that the IAGWSP also has been working to identify private wells (both irrigation wells and drinking water wells) downgradient of the area. Seven homes in a neighborhood northwest of Peters Pond, on Peters Pond Drive, were identified as having private wells. Six of the wells were sampled, and five came back nondetect for explosives and perchlorate. The sixth, however, had a detection of perchlorate at 1.007 ppb. The IAGWSP notified the regulators and the IART of the initial detection and then re-sampled the well, which came back with a 0.87 ppb perchlorate detection on the second sampling. Mr. Gregson said that before initial results from the private well became available, the IAGWSP sent a letter to the Sandwich Board of Selectmen requesting that the board select a point of contact for discussions regarding monitoring well locations on town-owned properties. The IAGWSP also sent a letter to the Sandwich Health Department asking for any available well construction information on the private wells and on irrigation wells located on the P.A. Landers gravel pit property. Mr. Gregson also noted that last Wednesday the IAGWSP notified IART members via e-mail of the initial perchlorate detection in the private well. At Wednesday evening's Senior Management Board (SMB) meeting, the IAGWSP briefed that group on the detection. The IAGWSP also mailed information to the homeowners with the affected private well, providing them with a fact sheet about perchlorate and its regulatory status. Last Thursday, the IAGWSP sent letters to 240 residents, including those in the Grand Oaks neighborhood, to inquire about any existing wells on their property. Records indicate that all of those residences are on town water, but there could be irrigation wells from which samples could be collected, and the IAGWSP requested permission to do so. Mr. Gregson also reported that the IAGWSP sampled the irrigation wells on the P.A. Landers property and the irrigation well at a nearby garden center. Those results should be available in the next day or two. Mr. Gregson further noted that after results from the second sampling of the private well came back last Friday, that information was sent to the regulators and the homeowners were notified via telephone. This past Monday, the IAGWSP e-mailed those results to Dave Mason at the Sandwich Board of Health and to Sandwich selectman Frank Pannorfi. Earlier today, the IAGWSP contacted the other homeowners with private wells to update them, confirm the results from their wells, and provide them with the opportunity to ask any questions. The IAGWSP also contacted the Sandwich Water District about sampling a community water supply well in the Peters Pond Park neighborhood. Mr. Gregson said that this afternoon IAGWSP staff members and Mr. Mason met to look for well locations and identified a couple of potential locations along the driveway access to the Forestdale School. He said that Mr. Mason has been designated as the IAGWSP's point of contact for access and real estate actions, and the Town of Sandwich has been very cooperative in helping the program move forward to drill on its properties. Also, IAGWSP staff members met with the town's facilities manager for the park property north of Peters Pond (the former Hewlett Packard recreation site) to discuss access to sample a couple of abandoned water supply wells on that property. Mr. Gregson also noted that the IAGWSP agreed to this morning's request from DEP to sample the affected private well for a third time. Mr. Gonser added that the IAGWSP also contacted the Fish & Wildlife department about a potential well site near Route 130. Mr. Pinaud referred to the map of the Eastern Boundary investigation area and inquired about the particle track lines. Mr. Gregson pointed out the blue and yellow lines that represent the permitted pumping rate and the daily average pumping rate ZOCs for the Sandwich municipal water supply wells. He noted that the ZOCs were generated using the IAGWSP's groundwater model and have been submitted to Jeff Rose at the Sandwich Water District for review. He said that Mr. Rose plans to run the information by his consultant to see if the ZOC depictions need to be adjusted. Mr. Gregson also pointed out the forward particle track from MW-319, and the backward particle track, which extends to the southern edge of the J-2 Range. He also referred to the "complicating factor" of the forward particle track from MW-310, which he noted is "heading off 90 degrees from the other one." He added that the backward particle track from MW-310 also goes back to the J-2 Range. Mr. Gregson also pointed out the forward particle tracks from MW-215 and MW-324, as well as the lines that represent the ZOCs for permitted and actual pumping rates associated with the Co-op's water supply well #1. Mr. Pinaud asked if it is correct that profile detections of perchlorate in MW-310 and MW-319 were greater than 4 ppb. Mr. Gregson confirmed that it is. Mr. Pinaud then noted that the forward particle track from MW-319 isn't extending toward Peters Pond and the detection on Peters Pond Road, which is "generally conceptually how it works" because of the pond's influence. Mr. Goydas of Jacobs Engineering stated that, as the map shows, the contamination at MW-319 migrates to the east. However, there could be contamination slightly south of there, where the IAGWSP is seeking to install additional wells, and that contamination would likely migrate toward Peters Pond. He said that the map shows specific particle tracks from specific known detections, but that doesn't mean that they will be the only detections. Mr. Cambareri asked Mr. Gregson to identify the cleared area on the map. Mr. Gregson replied that it is the Forestdale School. He also noted that the school is on town water and does not have an irrigation well. Mr. Cambareri said that he thinks the school does have a wastewater treatment plant. Mr. Gregson replied that it does have some type of on-site septic system. Mr. Cambareri also asked if the Coca Cola bottling plant is located in that vicinity. Mr. Gregson clarified that the plant is actually quite far to the north. Ms. Dolan asked if the IAGWSP had sent another letter to request access to sample the seventh private well on Peters Pond Drive. Mr. Gregson replied that the IAGWSP did send a second letter to the homeowner, but has not yet received a response. Ms. Dolan suggested that the IAGWSP "knock on the door" of that residence if it doesn't hear back from the homeowner by the end of the week. Ms. Adams inquired about the sources areas associated with the contamination seen at the Eastern Boundary. Mr. Gregson replied that the particle backtracks all go to the same general area, but a specific source area has not been pinpointed. He said that it appears that there are probably multiple source areas located in the J-2 Range, where a variety of activities occurred, including the operation of a melt/pour facility, test buildings, and a bunker. Ms. Adams asked if the backtrack information makes sense in terms of the timeframe when those sources originated. Mr. Gregson replied that it does make sense. Mr. Mullennix thanked the IAGWSP very much for its "extraordinary response" to the detection in the private well, and for informing and involving all the stakeholders immediately. Other Southeast Ranges Recent Unvalidated Detections Mr. Gregson showed a map of the J-3 Range and noted that the IAGWSP is working on removing the known source area there. He also said that there would be a discussion at next month's IART meeting about the J-3 Range RRA for groundwater, which involves the use of some existing FS-12 plume treatment system extraction wells. Mr. Gregson then reported that profile samples from MW-242A tested nondetect for perchlorate, and a screen was set in that well at 35 to 45 feet bwt. Mr. Gregson also reported that profile samples from MW-328, which was drilled as part of the ongoing L Range investigation and is located upgradient of the suspected source area, came back nondetect for perchlorate in 18 intervals, and also came back nondetect for explosives. Screens have been set in MW-328 and the IAGWSP is awaiting groundwater sampling results. Also, groundwater sampling results from MW-291 were nondetect for perchlorate and explosives. Agenda Item #5. Open Discussion Mr. Dow mentioned yesterday's Cape Cod Times article about the National Academy of Sciences (NAS) meeting regarding perchlorate, and then inquired about the relative timeframes for establishment of an EPA and a DEP perchlorate standard. Ms. Cassidy, who noted that she's speaking for EPA only, stated that the ongoing NAS review currently is scheduled to end in September 2004, but an extension request has been submitted. She said that she doesn't know that a final determination has been made on the request, but the review could be extended until the end of the year. Ms. Cassidy also said that after the Interagency Working Group receives NAS's review, it will decide on a course of action, which could include moving forward with the draft toxicity assessment that came out in 2002, or calling for further study - therefore the timeframe is unclear. She clarified that EPA will not put out the toxicity assessment (which leads to a reference dose [RfD], the scientific basis for any future regulations or standards setting) at least until the completion of the NAS review. Mr. Pinaud said that he can't provide a DEP draft timeframe tonight, but could get back to Mr. Dow with that information. He also noted that at DEP's request, the water suppliers sampled for perchlorate in April and are due to do so again in September in order to develop a database for water supplies across the state. He said that he's not sure how much time it will take to assemble those data and determine a maximum contaminant level (MCL) for perchlorate. Ms. Conron asked if NAS review committees typically operate by coming together and having "people give papers, many of them people from the government." Ms. Cassidy said that she cannot speak to how other reviews are done. However, she can report that this most recent meeting was the fourth such one where the scientific panel reviewed the perchlorate information. The panel has met at various locations in the country and it's her understanding that the meetings have involved the same set of presenters, although newer information may have been presented. Ms. Cassidy also noted that the meetings include an "open microphone" portion when the public is invited to share information and express concerns. Ms. Conron asked if there have been no independent studies on perchlorate, only government studies. Ms. Cassidy clarified that much of the information was collected from a variety of sources, including academic institutions and government-funded studies; a wealth of information is being reviewed. She also said that she knows that each of the meetings has been very similar, with the same presenters representing the various government agencies and the Interagency Working Group. Ms. Conron then asked if the Massachusetts DEP was asked to speak at the meeting, since it has issued an advisory level for perchlorate. Ms. Cassidy replied that it's her understanding that DEP was not officially asked to be part of yesterday's meeting agenda. However, Carol Rowan-West of DEP did speak during the open-microphone portion to express DEP's current position on the perchlorate issue. Ms. Conron also asked if it's correct that EPA will adopt whatever decision the NAS committee makes. Ms. Cassidy replied "not necessarily," and explained that the charge of the group is to provide a review of the draft toxicity assessment that EPA released in 2002, the peer review comments on the assessment, and any newer information that's become available. She said that "what's called the disposition of those comments will really depend on the nature of those comments, and how that would drive the next step for the agency." Mr. Hood said that the Technical Outreach Services for Communities (TOSC) group - and probably the IART members - would appreciate being notified in advance of the fifth NAS meeting regarding perchlorate. Mr. Murphy noted that the next IART meeting, to be held on June 22, 2004, will take place at the Forestdale School in Sandwich and will be scheduled to adjourn at 8:30 p.m. due to limitations imposed by the school. The July 27, 2004 IART meeting will take place at a Bourne location. Mr. Mullennix recommended that at the next IART meeting members be provided with the opportunity to discuss the possibility of consolidating the July and August meetings into one meeting in July. Agenda Item #6. Open Discussion Mr. Murphy said that the IART would meet next on Tuesday, June 22, 2004, at the Forestdale School in Sandwich. He then adjourned the meeting at 8:10 p.m. |
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| Administrative Notice |
