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Impact Area Review Team Meeting Minutes
Action Items:
Future Agenda Items:
Handouts Distributed at Meeting:
Agenda Item #1. Welcome, Agenda Review, Approval of February 28, 2006 IART Minutes Mr. Murphy convened the meeting at 6:05 p.m. and the Impact Area Review Team (IART) members introduced themselves. Mr. Murphy noted that a future IART agenda topics document was provided to the team, and Mr. Schlesinger asked why the tungsten mobility issue wasn't included. Mr. Gonser explained that the document contains only topics that are tied to particular studies; however, the tungsten issue, as well as any others, could be added on when significant information becomes available. Mr. Murphy asked if there were any changes to the February 28, 2006 IART meeting minutes. Mr. Pinaud referred to the last line in the first paragraph on page 6 and clarified that the Massachusetts Department of Environmental Protection (MassDEP) committed to having the samples that it had tested for tungsten retested at a lower method detection limit, but not at the same lab that was used by the Impact Area Groundwater Study Program (IAGWSP). He also referred to the first line in the first full paragraph on page 4 and clarified that MassDEP's proposed perchlorate standard is undergoing final review. The minutes were approved with these changes. Agenda Item #2. Responses to Action Items, Late-Breaking News Responses to Action Items from the February 28, 2006 IART Meeting Mr. Murphy noted that he had inadvertently provided the wrong "Inside EPA" article to the team in response to an action item request; however, Mr. Schlesinger had distributed the correct article at tonight's meeting. He also asked team members to verify the accuracy of the information contained in the IART contact list that he'd put together, and to let him know of any objections to having their personal information included, as the list would be available to the public. MassDEP Perchlorate Standard Mr. Pinaud announced that on March 14, 2006 MassDEP issued a maximum contaminant level (MCL) for drinking water and a groundwater cleanup standard for perchlorate, which was 2 parts per billion (ppb). The first public hearing associated with the new perchlorate standard will take place at 5:00 p.m., April 10, 2006 at the Peebles School in Bourne, and the second public hearing will occur at 3:00 p.m., April 11, 2006 at MassDEP Headquarters in Boston. Additional hearings will be held in the remaining regions, with a final hearing to take place in the Southeast Regional Office in Lakeville at 4:00 p.m. on April 20, 2006. The public comment period on the perchlorate standards will close on May 12, 2006. Mr. Pinaud also noted that he would let the team know about submitting comments by e-mail or via the MassDEP web site. Mr. Schlesinger asked Mr. Gonser if the IAGWSP would wait through the public comment period or immediately proceed as though 2 ppb were the new cleanup number. Mr. Gonser replied that from a regulatory standpoint, it's necessary to wait until the standard is duly promulgated. From a realistic standpoint and a planning perspective, however, the IAGWSP will be looking toward that standard to ensure that it can be accommodated. Mr. Schlesinger asked if the Army would issue a letter stating that perchlorate cleanup would be done to 2 ppb. Mr. Gonser replied that current policy establishes 24 ppb as the guidance until the federal or state government promulgates a rule, which would automatically be adopted at that time, without any special correspondence coming out of Washington. Mr. Schlesinger then asked if it's correct that since the 2 ppb perchlorate level applies only to Massachusetts, the military will clean up perchlorate to just 24 ppb elsewhere in the country. Mr. Gonser confirmed that the Department of Defense (DoD) policy is to clean up to 24 ppb, except in states that have passed their own standards. He also mentioned that California, New Jersey, and New York are moving in that direction. Mr. Schlesinger also asked if anyone could comment on the study about toxic rocket fuel. Mr. Olson replied that at this time the U.S. Environmental Protection Agency (EPA) knows no more about the study than Mr. Schlesinger does, from reading the article in Inside EPA.com, which, he noted, is not an EPA publication. Mr. Gregson mentioned that soil cleanup numbers for perchlorate are also included in the MassDEP regulations, and he encouraged team members to consider those numbers as well, the strictest of which he believes is 100 ppb, for a residential scenario. Ms. Conron asked when the state perchlorate standards would be finalized. Mr. Pinaud replied that he does not have a schedule for that, but it should happen sometime after the close of the public comment period, which is generally 30 days long. Ms. Adams asked if the soil cleanup number that Mr. Gregson mentioned is based on leaching to groundwater or to ingestion. Mr. Pinaud agreed to find out the answer to this question. He also noted that more information is available on MassDEP's web site, www.mass.gov/dep. Mr. Dow inquired about the status of state standards for RDX and HMX. Mr. Pinaud replied that based on what he knows, those standards are not yet out in draft form. Mr. Dow noted that he'd been under the impression that standards for RDX and HMX were on the same general time track as perchlorate. Mr. Pinaud agreed to check on the status of development of these standards and report back to the team. Mr. Mullennix said that he learned from MassDEP's web site that all the drinking water supply wells in the state will be able to meet the 2 ppb perchlorate standard, including those in Hadley, Millbury, Tewksbury, and Westford, where perchlorate had been detected, and in Bourne, where perchlorate had previously been detected in wells that now test nondetect. Although MassDEP is proposing the lowest perchlorate standard in the nation, it appears that it won't be an issue for the drinking suppliers, at least at this point. If California were to set a 2 ppb level, however, according to the American Waterworks Association 10% of the water systems in that state would in violation of that level. Mr. Mullennix noted that it seems to him that Massachusetts "conveniently" came up with a low standard that won't cause much repercussion across the state, except at the Massachusetts Military Reservation (MMR). He also said that it appears to him that MassDEP rejected all the studies that didn't "fit their mindset" and "spun" those that did in order to come up with the 2 ppb level. Agenda Item #3. Community Involvement Issues Membership Update Mr. Murphy reported that he's received no further membership applications since the last IART meeting, although several individuals have expressed interest. Team Merger Update Mr. Murphy noted that Jon Davis at the Air Force Center for Environmental Excellence's (AFCEE) Installation Restoration Program (IRP) office had offered to have Patrick Field, who facilitates the Plume Cleanup Team (PCT) meetings, arrange a meeting of citizen members from both the PCT and the IART. Mr. Minior stated that from AFCEE's standpoint, any further discussion of merging the IART and PCT is on the backburner for the foreseeable future. Mr. Schlesinger asked why that's the case. Mr. Minior explained that the subject was broached and the feedback received was that there's too much going on right now in both programs for the merger to be a workable solution. Mr. Schlesinger asked if a meeting of citizen members only from the two teams is still being considered. Mr. Karson said that he'd told the PCT about the IART's interest in a citizen members' meeting and had suggested that it might make sense to first have some sort of orientation session so the teams could learn about each other's programs. He noted that he'd also told the PCT that AFCEE would support the logistics to set up a meeting, but there didn't seem to be very much interest. Mr. Schlesinger said that he thinks that a citizens' meeting would be useful in that PCT members have had the experience of going through a process similar to what the IART members are now going through. However, he isn't certain that "a whole slew of orientation" would be needed. Ms. Conron said that she thinks that the experiences that the two teams are having are very different and that they have enough to do on their own, without joining together to have meetings that would be unbearably long. She also noted, however, that she's in favor of the kind of citizens' meeting that Mr. Schlesinger mentioned and thinks that it would be a useful way to learn from one another. Mr. Webb noted that he too is opposed to merging the two teams because of the voluminous amount of information that needs to be covered by the IART. However, he sees no reason not to have a citizens' meeting where the two groups could learn from each other's experiences. Mr. Murphy suggested that an effort should be made to set up a meeting. Mr. Schlesinger said that it might make sense to instead communicate via e-mail if there aren't enough citizens interested in meeting. Mr. Murphy said that he could add PCT contact information to the IART contact list that he is developing. Mr. Karson recommended having Mr. Field query both teams as to their interest in a citizens' meeting, and then take care of arranging the meeting, if warranted. He also said that members may want to schedule that meeting during a month when either an IART or a PCT meeting has been canceled. Ms. Conron said that she thinks it would be helpful to have Mr. Field coordinate the meeting, which she envisions as an informal event that would last an hour or two. She then inquired about the number of citizen members on the PCT. Mr. Karson replied that he believes there are 11 citizen members on the PCT. Mr. Schlesinger noted that he's interested in knowing about the "lessons learned" by the PCT while going through the remedy selection process, as the IART will be doing over the next several years. Ms. Conron said that she would not object to attending a citizens' meeting during the same month as an IART meeting, and added that her interest in a citizens' meeting is the same as Mr. Schlesinger's. Agenda Item #4. Range Soil Remedial Investigation Mr. Gregson noted that the L Range and Former K Range are different than the J Ranges in that both were used only for military training activities, with no known evidence of contractor operations there. Also, both were used for firing smaller-diameter projectiles such as 40-mm grenades and 3.5-inch antitank rockets. To date there is no evidence of disposal activities at these ranges, and the volume of munitions used there is far less than were used at the Central Impact Area, where thousands and thousands of high-explosive rounds were used. Consequently, relatively little contamination has been detected there. Mr. Gregson then noted that the L Range Report pertains only to a soil remedial investigation, while the Former K Range Report pertains to both soil and groundwater. Mr. Gregson showed some photographs of the L Range and pointed out a target, the observation tower, a storage shed, and the area from which weapons were fired. He also noted that the L Range study area includes the L Range itself (which was used first as an infiltration course from the 1940s to 1950s, and then as a grenade launcher range from the late 1960s through early 1970s) as well as Area 46 (where the IRP did its Fuel Spill 12 [FS-12] source area treatment work) and Cleared Area 11 (identified as an open area on aerial photographs). Mr. Gregson stated that the L Range is an area of concern because of some low level RDX and perchlorate groundwater contamination detected in several wells downgradient of the range. The L Range investigation to date has included research into historical records, soil sampling, and some geophysical work that was somewhat limited because of difficult access associated with the number of potentially high-explosive 40-mm grenades that exist on the range. Nevertheless, 470 soil samples have been collected from 60 locations, with four at the firing points at the L Range, 27 at the targets, ten at Cleared Area 11, and ten at Area 46. Each sampling location involved multiple sample depths and multiple analyte suites. Mr. Schlesinger asked if the study area was covered by the air magnetometry (air mag) survey. Mr. Gregson replied that it was and noted that some limited ground-based magnetometry was done there as well. He also showed a figure and pointed out the sub-areas that make up the L Range study area, and then showed a conceptual site model figure. He explained that weapons systems fired downrange, the RDX and perchlorate leached into the groundwater, and the contaminants moved downgradient with groundwater flow. He also said that it's believed that a number of the plumes, if not all of them, have depleted sources and have detached from the source areas as they move downgradient. Ms. Adams inquired about the reference to an Infiltration Range on the conceptual site model. Mr. Gregson explained that for a period of time the L Range was using as an infiltration training range where troops worked their way through a certain course and learned how to advance their positions. He also noted that a lot of the grenade launchers that were later used on the range were handheld. Mr. Gregson then showed a plan view figure and pointed out the J-3 Range plume and the L Range RDX contours (nondetect and 2 ppb). He also noted that based on data from the monitoring wells, it appears that the source is depleting and the plume is moving off downgradient. Mr. Schlesinger pointed out that Mr. Gregson mentioned a depleted source when he showed the conceptual site model, but just now mentioned a depleting source. Mr. Gregson explained that the RDX source is depleted, but it appears that an area of perchlorate contamination may still be attached to a weak source area in the northern part of the range. Mr. Dow brought up the subject of potential receptors and that the plumes supposedly would attenuate before reaching them. Mr. Gregson explained that the contaminant concentrations are very low and aren't expected to migrate very far because there isn't enough mass to drive them. He also noted, however, that the plumes are headed toward FS-12 extraction wells, which are anticipated to capture them. Mr. Gregson then reviewed the findings of the L Range study, as follows: RDX and perchlorate were not detected in any soil samples from the study area; the groundwater contamination seems to have originated from a depleted source - a likely explanation for the declining/detaching plumes; based on modeling it's unlikely that the contamination downgradient of the L Range is unrelated to that area; and based on the sampling program it's unlikely that the L Range contamination originates from a source that's not yet been identified. Mr. Gregson stated that because of the absence of significant detections of the contaminants of concern, the IAGWSP has concluded that no further remedial action for soil is required at the L Range. He also noted, however, that the unexploded ordnance (UXO) that exists at the range is a lingering concern that will be assessed as a potential threat to groundwater at a later date. He further noted that the IAGWSP hasn't yet received written comments from the regulators on the L Range Report. Mr. Olson noted that EPA is concerned about the UXO component being separated from the soil component. He said that it's uncertain whether or not UXO is contributing to groundwater contamination and EPA isn't sure how the IAGWSP can make a decision on the soil component without at least understanding the conceptual model for the UXO. Mr. Schlesinger asked if the air mag work at the L Range had been inconclusive. Mr. Gregson replied that a problem with the air mag survey is the chain-link fence installed around the range that gives off a very "hot signal" that may have masked some of the anomalies there. He also noted that some ground-based geophysics were done on the range as well, the details of which are contained in the L Range Report. Mr. Schlesinger expressed some concern that in the absence of information the IAGWSP wants to just let the L Range contamination go. Mr. Gregson replied that the levels of groundwater contamination that likely originate from the range are very low - barely at the health advisory for RDX and below 2 ppb for perchlorate. Also, these contaminants weren't detected in the soil so it appears there's no lingering soil source. Mr. Gregson also said that the IAGWSP agrees with the regulators that the UXO component requires careful consideration because of its potential to be a future source of groundwater contamination, and this is something that will be examined. Mr. Schlesinger then asked if the extent of the L Range plumes is well understood. Mr. Hill noted that the groundwater remedial investigation (RI) was completed in 2005, and shown on the graphics are interpolations of existing data. He also said that the fact is that the contaminants that have been detected are quite low in concentration and the existence of the FS-12 treatment system in the downgradient area mitigates the value of pursuing further drilling in that area. Mr. Hill then stated that in reality the aquifer's capacity for attenuation is near the point where it absolutely overwhelms the concentrations that are there. The plume appears to be stable and declining and no trends are being seen that indicate that concentrations are increasing at any of the measuring points. Mr. Schlesinger asked if this means that natural attenuation will be the answer for all 2 ppb plumes. Mr. Hill replied that the recommendations made with respect to L Range contamination apply to L Range contamination only. Ms. Conron asked why the UXO aren't simply picked up and removed from the site. Mr. Gregson replied that the Massachusetts Army National Guard manages activities on the ranges, and from an immediate safety standpoint, the Guard has in place the controls of the chain-link fence and overall restricted base access. With regard to environmental impacts, however, it's necessary to balance them with the cost and safety concerns associated with sending individuals out to the range to remove the UXO. Ms. Conron asked why the range looks so bleak compared to the relatively lush vegetation around it. Mr. Gregson replied that he doesn't think it has to do with stressed vegetation because of contaminants, but is probably merely a matter of the top soil having been removed at some point during the range's use. He noted that on Cape Cod it takes a long time for vegetation to reestablish itself after top soil is removed. Ms. Grillo asked if any UXO clearance has ever been done at the L Range. Mr. Gregson said that he thinks that the report mentions some UXO clearance having been done at one point, but based on observations made during sampling some UXO remains at the site. Ms. Grillo also asked if the area is fenced in because it was a grenade range. Mr. Gregson replied that that is correct. Ms. Grillo asked when the fence was installed and Mr. Gregson replied that he does not know. He also mentioned that the IAGWSP will look at a risk assessment as part of an RI and will look at a range of alternatives as part of the feasibility study (FS), including a natural attenuation alternative and an active treatment alternative. Mr. Dow asked how the IAGWSP can be sure that it's identified all the detached plumelets downgradient, given that the source area dates back to the 1940s. Mr. Gregson pointed out on the map all the downgradient wells that were sampled, including those that are part of the FS-12 system. He also said that while there may be other detections out there, it's important to ask whether that information needs to be known in order to come up with an overall strategy of assessing groundwater impacts and dealing with the plumes. Mr. Dow noted that FS-12 is a detached plume and the IRP has monitoring wells on the southern edge of Snake Pond to ensure that the plume hasn't traveled beyond the extraction well fence. Mr. Gregson pointed out a series of wells in that area that the IAGWSP recently installed and sampled for RDX and perchlorate, all of which tested nondetect. He also noted that unlike FS-12, which was a very significant plume when first discovered, there's not a lot of mass driving the small areas of L Range contamination. Mr. Dow said that the mass of contaminants in the 1940s to 1960s isn't known; rather, it's only known that there's a small amount of mass in the groundwater and currently no RDX or perchlorate in L Range soils. Mr. Gregson replied that the IAGWSP has a snapshot of its interpretation of "what we see in groundwater" and no additional evidence of anything bigger farther downgradient. He added that he thinks that no significant plumes have developed because of the limited use of the range and the relatively low level loading of contaminants onto the surface soil. Mr. Gonser mentioned that historical records indicate that initially the range was used as an infiltration course, which would have involved the use of very few munitions, weapons, and so forth. Mr. Minior noted that when the IRP conducted the RI at FS-12 around 1993, samples were tested not only for volatile organic compounds (VOCs), but also for semi-volatile organic compounds (SVOCs), which would have picked up potential explosive compounds, but to his recollection none were detected. He also said that the IRP now samples just for fuel components and ethylene dibromide (EDB). Mr. Schlesinger remarked that unless testing for RDX and perchlorate, they won't be found no matter how many wells there are. He also inquired about the depth of the well screens relative to the depth of the plumelets. Mr. Gregson said that the point is that since the FS-12 RI was conducted, the IAGWSP has done a lot of additional work to find further contamination from the L Range - not only by sampling appropriate screen depths in existing IRP wells, but also by drilling new IAGWSP wells like MW-246. Mr. Schlesinger stated that it still doesn't sound as though the IAGWSP has addressed the issue of downgradient wells being able to assess whether there's mass past where it's expected to be. Ms. Dolan recommended presenting the L Range Groundwater Characterization Report to the IART. Mr. Gregson agreed with this recommendation, but added that given the well coverage and the fact that there was no problem identifying the J-3 Range plume in that area, the IAGWSP is quite confident that there isn't another larger plume there that was missed. Mr. Mullennix remarked that in light of the well coverage at the L Range study area and the oversight provided by EPA and MassDEP he's confident that the IAGWSP will come to the right conclusions. Agenda Item #5. Former K Range Remedial Investigation Update Mr. Gregson showed an aerial photograph and noted that the Former K Range, which is basically a forested area that hasn't been used in some time, is located just to the left of Greenway Road and is approximately 800 by 1,200 feet in size. At the entrance to the Former K Range is a small arms range known as P Range, which, although still usable, has not been used in a quite a while, primarily because of its proximity to adjacent neighborhoods. Mr. Gregson stated that the Former K Range RI report, which was issued in December, looked at both soil and groundwater. He also noted that the site was used as a rocket range in the 1960s, as a grenade launcher range in the late 1960s through early 1970s, and then later as a pistol range in the 1980s. To date there has been no evidence of any disposal activities at the range. Mr. Gregson noted that the Former K Range was part of the overall site-wide investigation known as Phase 2B, but because it had the potential for soil and groundwater contamination that required further investigation, it was pulled out as a separate site in order to asses current and future groundwater impacts. As part of the assessment two cleared areas were identified downrange as potential former targets. This was based on the discovery of 3.5-inch high-explosive and practice rockets and 40-mm high-explosive and practice grenades, which were consistent with what was known about the history of the range. Mr. Gregson also noted that the Former K Range was included in the air mag survey and that some ground-based electromagnetic and magnetometer surveys also were performed there as part of the munitions survey program. The IAGWSP investigated 10 anomalies at the site, which turned out to be ordnance and munitions scraps - antitank rockets and rocket components that had been fired downrange, and again were consistent with the site history. Mr. Gregson then reported that more than 350 soil samples were collected at the site. Groundwater sampling was conducted as well; the IAGWSP installed MW-170 and later looked at data from a number of other downgradient wells, including MW-324, MW-368, MW-355, MW-399, and MW-366. Mr. Gregson showed an aerial photograph with an overlay of the areas of investigation (A through F) that were addressed as part of the Former K Range study. He noted that soil samples were taken from each of the areas and that MW-170 was drilled specifically to look at groundwater from Area E. He also said that later a number of additional wells were installed primarily to look at groundwater contamination coming from the J-2 Range, but also to look at profile samples for shallow contamination that could be coming from the Former K Range. Mr. Gregson reviewed the following soil findings: most concentrations detected were less than MMR soil screening standards; RDX, TNT, HMX, and 2A-4,6-DNT were detected at concentrations above screening levels in Areas C and E; no explosive compounds were detected in any samples from Areas A, B, D, and F; and perchlorate was detected in two samples from Area E, with one of those detections slightly above screening level. He also reviewed the following groundwater findings: at MW-170, three sampling events for a full suite of analytes and six rounds total for explosives, metals, and perchlorate resulted in the detection of no explosives, but some low levels of di-n-butyl phthalate at 0.42 ppb and 0.27 ppb (the state level for which is 500 ppb) in one sampling round: at MW-355 no detectable concentrations of explosives or perchlorate in three sampling rounds; and nondetect results from profile samples taken at the six other locations as well. Mr. Gregson said that it appears that there is no contamination coming from the Former K Range. Also, that there's no significant soil contamination there, based on the risk assessment. Therefore the recommendations put forth in the RI report were that no remedial actions are necessary and that long-term monitoring would be appropriate. Mr. Gregson also noted that EPA and MassDEP have commented that they believe that additional investigation is needed to address soil and groundwater data gaps. The regulators have asked for soil data from depths greater than 12 inches and for a direct-push investigation to evaluate shallow groundwater within the Former K Range boundaries. Mr. Gregson noted that the IAGWSP is working with the regulators to look at their specific areas of concern. He further noted that the UXO issue at the range needs to be assessed in terms of a potential future groundwater source, and that MW-170 has been identified for annual monitoring as part of the Former K Range groundwater monitoring program. Mr. Schlesinger asked if 2A-4,6-DNT is a daughter product. Mr. Gregson replied that it is a breakdown product of explosives, and noted that the detections in soil were very sparse. He also explained that when doing a risk assessment, the IAGWSP compares observed detection levels with initial screening levels provided by EPA as preliminary remediation goals (PRGs) or soil screening levels (SSLs). If higher, they become part of the risk assessment to determine what the overall risks are based on site-specific conditions. Mr. Schlesinger then asked if soil sampling at a depth greater than 12 inches would be done at the same or at different sampling locations. Mr. Gregson replied that the IAGWSP still has to work this out with the regulators, who have presented their concerns about deeper soil data. He also spoke about reviewing the available soil data to see if there are any increases with depth that might warrant additional sampling, and also reviewing the conceptual model of how munitions were used at the range and what the likely depth of contamination might be. Mr. Gregson noted that given the history of use at the range, however, it's expected that the highest concentrations would be seen right at the surface. Mr. Mullennix inquired about MW-315. Mr. Gregson replied that that well was installed as part of the J-2 East plumes investigation, and that nothing was seen there that would be from the Former K Range. Ms. Adams asked about the level of confidence in the groundwater contours in the area, given that it's quite near the top of the mound. She also noted that the accuracy of the groundwater contours could affect whether the downgradient points are located correctly. Mr. Gregson acknowledged that "there's quite a curve to the one groundwater contour" shown on the figure. He also noted that the top of the groundwater mound, which is located in the lower left corner of the map, does shift over time and added that although there's just one particle track on the map, if others were drawn "they'd fan out from the top of the mound." Mr. Gregson also said that the wells being monitored as part of the investigation are "fairly well spread out" such that they would indicate if there were a significant plume coming from the Former K Range. Mr. Dow inquired as to the type of metals detected in MW-170 at concentrations below MMR screening levels. Mr. Gregson replied that he would have to look up this answer in the report and come back to the team with that information. Mr. Dow mentioned the possibility that earthworm activity could be "mixing things up" such that shallow contamination is transported beneath the top foot of soil. He then asked if a lot of earthworms or other soil micro-fauna were observed during soil sampling. Mr. Gregson replied that although he doesn't know what was observed in the field, he does know that the soil at the site is extremely sandy and low in organics, and therefore an earthworm wouldn't have much hope of finding food the deeper it goes. Mr. Dow said that he's aware of marine systems in which organisms "bioturbate" the surface sediments much deeper than a foot. Mr. Gregson replied that there are a lot more organics for organisms to consume in marine sediments than there are at the Former K Range. Mr. Schlesinger asked if the phthalate that was detected was the same type often noted in reports to be a byproduct of sampling. Mr. Gregson clarified that that is bis-2-ethylhexyl phthalate, whereas the one mentioned this evening is a propellant-related compound, di-n-butyl phthalate, which was detected in one sampling round but hasn't been detected again since. Agenda Item #6. Demolition Area 1 Groundwater Rapid Response Action Annual Update Mr. Nixon stated that the IAGWSP has remediated the Demolition Area 1 (Demo 1) source area, a 7.4-acre natural kettle hole about 45 feet deep, located in the central part of MMR, that was used from the 1970s until about 1997 for the destruction of munitions and also for demolition training. The Demo 1 Rapid Response Action (RRA) for soil involved the removal of 27,000 tons of soil that was treated and then returned to the Demo 1 hole. This effort removed the source of Demo 1 groundwater contamination. Mr. Nixon also reported that the Demo 1 RRA for groundwater involved the installation of a treatment system at Pew Road and another one at Frank Perkins Road, closer to the source area. He noted that the Demo 1 RI, FS, and remedy selection plan all have been completed and the decision document is close to being finalized, after which the process will move forward with design and construction of a comprehensive remedy that will build on the existing RRA systems. Mr. Nixon showed a series of photographs of the Demo 1 site - pre-excavation, during excavation, and post-excavation - and noted that some trees and some erosion-control materials were added after the post-excavation photo was taken. Ms. Conron inquired about the source of the trees. Mr. Nixon replied that the trees, which are mainly "little pine trees, little oak, and blueberry type things" were taken from alongside roads on base. Mr. Nixon also showed a photo of the thermal treatment unit, where the Demo 1 soils were treated. Mr. Nixon noted that the contaminants of concern at the Demo 1 plume are RDX, other explosives, and perchlorate. The perchlorate detections extend about 10,300 feet, the RDX detections extend about 7,000 feet, and both plumes are about 80 feet thick at the widest part. Mr. Nixon then reported that new data from the two wells in the source area (MW-19 and MW-73) show that they've tested nondetect for perchlorate, which is good news. He also said that the past maximum RDX concentration in the plume was about 370 ppb and is now about 140 ppb, and for perchlorate was about 500 ppb and is now about 100 to 120 ppb. Mr. Nixon stated that the RRA groundwater treatment systems began operating in September 2004 and will continue to operate until the comprehensive groundwater remedy is constructed, by about the end of this year. He noted that the Frank Perkins Road system is comprised of one extraction well, a treatment plant (three containerized units), and two reinjection wells, and treats 220 gallons per minute (gpm). The Pew Road system is comprised of one extraction well, a smaller treatment plant (one containerized unit), and one reinjection well, and treats 100 gpm. Mr. Nixon reported that the RRA systems treated a total of 170 million gallons of water from system startup through August 2005. The comprehensive remedy will increase the flow to 906 gpm, thereby shortening the time required to remediate the plume. Mr. Nixon noted that the Demo 1 Groundwater Response System Performance Monitoring Program that he would be discussing this evening pertains to treatment system sampling (September 2004 to August 2005), hydraulic monitoring (September 2004 to August 2005), plume monitoring (September 2004 to June 2005), and fate and transport modeling, which is designed to predict "where the plume will go and at what concentrations." Mr. Nixon showed a schematic diagram of the Pew Road treatment system and pointed out where samples are collected: influent - to track the mass of contaminants removed from the plume: midpoint - to determine when the filter media has reached its capacity; and the effluent - to confirm removal of contaminants. He noted that influent concentrations at Pew Road are now generally 10 to 12 ppb, but had started out somewhat lower. He also showed a schematic diagram of the Frank Perkins Road system and noted that each of the three containerized units there treats 73 gpm. Mr. Nixon showed an influent concentration graph for the Pew Road system and said that it appears that a pulse of perchlorate contamination came through that spiked the influent concentration up to about 15 ppb, which settled to about 12 ppb by the end of the performance monitoring period, and has since trailed off to about 10 or 11 ppb. He also showed an influent concentration graph for the Frank Perkins Road system, which he described as "more traditional" in that it begins with a high concentration that tapers off over time. He explained that extraction begins at the most contaminated part of the plume, but over time water is drawn in from the outside, less-contaminated edges and dilutes the influent concentrations. He also mentioned that the RDX "hasn't really changed too much." Mr. Nixon reported that through August 2005 the Demo 1 RRA systems treated about 150 million gallons of groundwater and removed 19 pounds of perchlorate and nearly six pounds of explosives from the plume - or about 20% of the total mass of perchlorate and about 10% of the total mass of RDX. He also reported that no breakthrough occurred at the Frank Perkins Road system during the first year of operation. The need for a couple of change-outs at Pew Road, however, led to a decision to modify that system early this year by adding ion exchange resin (IX) to the treatment train. Mr. Nixon then noted that the Pew Road treatment plant has been operational 95% of the time, and the Frank Perkins Road system 96.5% of the time. Downtime was due primarily to power outages, but also to carbon change-outs at Pew Road, and to maintenance. Mr. Mullennix inquired about the status of the comprehensive response action. Mr. Nixon replied that the decision document that outlined the comprehensive remedy is close to being finalized, and it's hoped that construction will begin this summer and be completed by the end of 2006. Mr. Mullennix asked about the purpose of the comprehensive remedy. Mr. Nixon explained that over time (about 50 years) the RRA system would accomplish the same goals as the comprehensive remedy, which is predicted to clean up the plume to acceptable levels in about 11 years. Mr. Mullennix asked if the model has been recalibrated based on the first year of data. Mr. Nixon replied that it wasn't necessary to recalibrate the model because the hydraulic monitoring showed that the original model was right. Mr. Mullennix questioned why it would take 50 years to clean up the plume with the RRA system, when it was able to remove 20% of the total mass in the first year. Mr. Nixon explained that that kind of removal level typically isn't maintained as concentrations decrease, with less contaminant being removed in the out years such that "it's not linear." Mr. Schlesinger asked if it's correct that perchlorate concentrations are around 10 ppb in the area from Frank Perkins Road up to the kettle hole. Mr. Nixon clarified that the maximum concentration in that area is higher, around 40 to 50 ppb. He also explained that the influent concentration in the extraction well is always lower than the maximum concentration in the aquifer because the well pulls in water not only from the center of the plume, but also from its edges and vertically, such that a blending occurs. Ms. Conron inquired about the influent concentration graphs, and Mr. Nixon showed the one for Frank Perkins Road. Ms. Conron then asked why the RDX curve isn't typical, in that it doesn't drop off like the perchlorate curve does. Mr. Minior said that it's because the RDX is more homogeneous throughout the column. Mr. Nixon agreed that it's disbursed differently. He also said that it could have something to do with perchlorate being a much more soluble compound, and therefore the concentrations are more "spiky," while the RDX concentrations tend to more consistent. Mr. Nixon also suggested that the RDX line does have a bit of the classic curve, but it's just not as pronounced. Ms. Conron asked if this means that it will be more difficult to remove the RDX contamination. Mr. Nixon replied that that is not the case and noted that neither RDX nor perchlorate sorb readily to soil particles, and both move freely through the groundwater. He also said that it might be slightly more difficult to remove the perchlorate, but only because it's a little more spread out. Mr. Dow asked if it's any harder to change out ion exchange resin than granular activated carbon (GAC). Mr. Nixon replied that the mechanics are exactly the same, so it takes the same level of effort to change out either medium. He also noted, however, that GAC removes about 1/10 to 1/20 the amount that ion exchange resin does, so the ion exchange resin is expected to last much longer. Mr. Nixon further noted that the ion exchange resin doesn't remove explosives, only the perchlorate, as perchlorate is a negatively charged anion and the ion exchange resin has a positive charge on its surface. Mr. Dow asked if the GAC had been removing the perchlorate at Pew Road before the system was modified to include ion exchange resin. Mr. Nixon confirmed that it had, by the end of the second vessel. He also noted that no perchlorate, RDX, or other explosives have ever been detected in the system effluent. Mr. Mullennix noted that data on the influent concentration graph runs through July 2005 and asked what has occurred since that time. Mr. Nixon replied that there hasn't been very much change at either of the RRA systems since that time, and added that the classic plant influent curve is "a decline to an asymptotic level, and that's kind of what we're approaching…" Ms. Adams asked Mr. Nixon to explain why influent concentrations of perchlorate at Pew Road were higher than predicted. Mr. Nixon replied that this is believed to be due to pulses of contamination migrating downgradient, brought about by the pattern of loading at the source area and the amount of rain infiltrating the ground. Mr. Nixon then continued his presentation by discussing the hydraulic monitoring program, the purpose of which is to assess the influence of pumping on the aquifer and identify the capture zones and the extent of contamination being pulled in. He showed a graphic that illustrated the modeled drawdown at Pew Road and noted that the expected drawdown matches up with what's being observed. Mr. Schlesinger asked if Mr. Nixon was referring to drawdown of the surface of the water table and Mr. Nixon confirmed that he was. He also showed a graphic that illustrated the modeled drawdown at Frank Perkins Road, and then a cross-section figure that illustrated the observed drawdown, pointed out the cone of depression, and noted that it was "even closer" to the model prediction. Mr. Nixon noted that because the model-predicted and observed drawdowns are the same, it's believed that the various parameters in the model (such as soil transmissivity, conductivity, and porosity) are right, and the model doesn't need to be recalibrated at this time. Mr. Schlesinger asked about drawdown effects on surface water bodies. Mr. Nixon referred to the Frank Perkins Road graphic and noted that although water levels have actually risen because of the amount of rain recently, water levels have not been affected as compared to background, and no drawdown has been seen at Opening Pond. He then showed another Pew Road graphic, pointed out the limit of drawdown, which he noted is only about 300 feet, and said that the ponds "are quite a ways further down." Mr. Mullennix asked Mr. Nixon to explain the figure that shows the perchlorate plume contours, and how treatment is affecting them. Mr. Nixon noted that the darkest-colored plume contour represents concentrations of more than 100 ppb, while the increasingly lighter-colored contours represent increasingly lesser concentrations. He then explained that when an extraction well is operating it draws water in from the outer edges, such that "all these concentrations here" mix together and become diluted, thereby creating "an averaging effect" that's also seen in the vertical. This is why there could be a 100 ppb detection of perchlorate in the plume, but only 10 to 15 ppb in the influent. Mr. Panni asked if the model would have to be recalibrated because of the state's pending 2 ppb perchlorate standard. Mr. Nixon replied that standards don't really matter to the model - the model is going to predict "what's coming and what's going" no matter what the standards are. Mr. Nixon then showed a composite capture zone figure for Pew Road and Frank Perkins Road and noted that it includes particle tracks to illustrate the effects of the wells. He zoomed in on the Frank Perkins Road capture zone area, and then on the Pew Road capture zone, which he noted is somewhat narrower but does capture "all the significant contamination," while the lesser concentrations dissipate before reaching anywhere near the base boundary. Mr. Nixon then noted that three new extraction wells are going to be installed as part of the comprehensive remedy. He also mentioned that hydraulic monitoring actually involves the use of an electronic tape that's calibrated in inches and feet to take readings at a variety of wells before and after system startup. Mr. Dow noted that Mr. Nixon had mentioned that the water level is currently fairly high in the groundwater table, and then asked whether there's a climatological effect on the size of the cone of depression. Mr. Nixon replied that he's not sure, but he doesn't think it would make an appreciable difference. Mr. Minior asserted that "the pump doesn't care." Mr. Nixon said that while he thinks Mr. Minior is right, he would like to check with a hydro-geologist and provide Mr. Dow with an answer. Mr. Dow then asked where the treated water from Frank Perkins Road is reinjected, and whether it's up in the source area. Mr. Nixon replied that the water is reinjected lateral to the extraction well and outside the plume. Mr. Gonser added that it's not in the source area, but directly on the same road as the extraction well - just north and south. Mr. Nixon also said that in the case of both RRA systems, the treated water is being reinjected "way deeper than the plume" such that it doesn't create "much squishing effect at all." Mr. Dow noted that Mr. Nixon had talked about there being no effects on Opening Pond, and asked about effects from reinjection on other water bodies. Mr. Nixon replied that Opening Pond is the only surface water body that's really anywhere near the Demo 1 plume. Mr. Dow mentioned the ponds near the Rod & Gun Club, but Mr. Nixon said that those are too far away to be affected. Mr. Nixon continued his presentation by discussing plume monitoring. He showed a map depicting three regions of the plume - upgradient, middle (between the two treatment systems), and downgradient. He also mentioned the pulse of perchlorate contamination identified at MW-210 via a detected concentration of about 100 ppb, which occurred after the reporting period, when the highest perchlorate concentration detected was about 50 ppb. He also noted that maximum RDX concentrations have decreased from about 370 ppb to about 140 ppb. Mr. Nixon then stated that source area concentrations have also decreased and pointed out MW-19S, which at one time had an RDX detection of 100 ppb, which went down to 14 ppb during the reporting period. He also displayed graphs showing source area trends and reminded the group that currently there's no perchlorate left in the groundwater beneath the source area. He also said that RDX concentrations aren't dropping off quite as quickly because RDX doesn't dissolve out of the soil as quickly. Mr. Schlesinger inquired about any detections at MW-352, a sentinel well near the leading edge of the plume. Mr. Nixon replied that there still have been no detections there. Mr. Schlesinger then mentioned that RDX was detected at MW-225. Mr. Nixon said that using a conservative approach, travel times were calculated based on that detection in order to determine the trailing edge of that contamination. He said that there might not be any more RDX in that area than "just one little hit." Mr. Nixon referred to the middle region of the plume, mentioned the pulse of perchlorate contamination that came through there, and noted that otherwise concentrations are generally decreasing, with vertical and horizontal narrowing of the plume being seen. He also said that the model indicates that concentrations getting by the Pew Road system will dissipate and not be a problem in the future. He then noted that the RDX concentration detected at MW-225 was 0.33 ppb. Mr. Schlesinger asked if the comprehensive remedy will include active treatment "downgradient of these roads." Mr. Nixon replied that the comprehensive remedy includes a contingency that if modeling or actual data indicate that the plume is going to migrate farther then expected, an additional extraction well will be installed "just on the other side of this pond" to capture that leading edge. Mr. Mullennix inquired about a cost analysis for the comprehensive remedy versus just leaving the RRA systems in place. Mr. Nixon replied that the cost analysis is detailed in the feasibility study, and while he doesn't recall the exact numbers, he does remember that it was less expensive to build the comprehensive five-well system because it shortens the operating time. Mr. Nixon then explained that hydraulic monitoring and plume monitoring data were assimilated into the model, which was rerun in order to help determine where the plume is expected to go and whether any changes need to be made to system operations (which was determined not to be the case). He also said that there's some doubt as to how much influence North Pond will have on the plume, since it's only about six feet deep. Therefore, two different simulations were run for the toe of the plume - one with the pond exerting influence on the plume, and one without the pond exerting influence on the plume. With the pond's influence it tends to cause the dilution of the plume to happen a little sooner and a little farther away from the base boundary, but even without the pond's influence the plume is expected to dissipate within the base boundary. Agenda Item #7. Open Discussion - Tungsten Update Mr. Gonser reported that the U.S. Army Environmental Center (AEC) has taken a second round of samples to find out if they substantiate the first round of results from the tungsten monitoring. Results from the second round are expected soon. He also noted that the U.S. Center for Health Promotion and Preventive Medicine (CHPPM) is conducting a tungsten toxicity study, which is moving along well, with study results expected by early summer. In addition, the Massachusetts National Guard is working with the U.S. Geological Survey (USGS) and the regulatory community to do some additional sampling at select ranges - the Bravo Range, where tungsten was initially detected, and the Sierra East and Sierra West Ranges, which are upgradient of water supply wells. Mr. Gonser said that it's hoped that by early summer everyone will have a better idea of health and mobility impacts from tungsten. Mr. Mullennix noted that at last month's IART meeting he was under the impression that test results from a second sample from Bravo Range were imminent. Mr. Gonser replied that the second round test results should be available as soon as this week. Mr. Mullennix then asked if the well that had the tungsten detection had been examined to ensure that there was no potential for short-circuiting there. Mr. Gonser replied that it was examined with that possibility in mind and it doesn't appear that short-circuiting was an issue; it's believed that the initial detection was accurate. Mr. Mullennix asked if tungsten ammunition continues to be used at MMR. Mr. Gonser replied that the Governor and the Adjutant General decided to discontinue firing tungsten until more is known about the mobility and toxicity issues. Mr. Mullennix asked if lead ammunition is being used. Mr. Gonser replied that is it not, although the Guard is proposing a long-term management plan that might result in going back to firing lead, since there are more weapons systems that can use lead. For the time being, however, the plan is to use plastic bullets or conduct training at alternate locations. Mr. Schlesinger asked if this means that tungsten would be put into the water table at other locations. Mr. Gonser replied that installations are being informed of the new mobility issues associated with tungsten, but he doesn't know that any other installations are using tungsten at this point. Therefore he thinks that standard lead bullets would be used in the event that training was to occur elsewhere, such as Fort Drum. Mr. Schlesinger noted that the question then is whether tungsten is being used at other bases, and if so, whether the groundwater there is being tested. Mr. Gonser said that tungsten has been fired at other bases, but from the briefings he's heard it's his understanding that it's not being used at any bases currently. He also noted that AEC intends to expand its tungsten mobility study to include at least two other installations beside MMR where tungsten has been used. In addition, AEC has been conducting tungsten mobility laboratory studies that are basically reinforcing what's been found at MMR - that "tungsten combines with oxygen, becomes tungstate, then becomes mobile, and then dissolves and moves to the groundwater." Mr. Mullennix said that he's distressed to hear that without the options of tungsten or lead, troops will have to go elsewhere to train. He noted that the primary purpose of the base is to serve as a local training site for the Massachusetts National Guard, and "somewhere else" is a long way to go for weekend training. Mr. Gonser agreed that this is a big concern, that an 8.5-hour drive to and then from Fort Drum for a weekend is not a very good training experience or use of funds. He then said that AEC and CHPPM are moving along their mobility and toxicity studies as quickly as possible so they can get the answers that are needed in order to make decisions on how to proceed, and the Guard is working on a long-term management plan to perhaps return to using lead ammunition. Mr. Gonser also stated that firing weapons is the most essential part of any military training. Mr. Mullennix said that he appreciates that the studies are moving as quickly as possible. He also said that all the data that he's seen on lead contamination in groundwater associated with firing of small arms indicates that lead is quite immobile, meaning that when it rains it does not dissolve and migrate into the groundwater. He further noted that he believes that the regulatory agencies acquiesced several years ago to no longer testing for lead in groundwater at MMR simply because no lead was being found there. Mr. Gonser said that as part of its small arms investigation the IAGWSP will sample for lead in order to make a strong case that lead isn't mobile, but has more investigation to do to be able to confidently say that. Mr. Schlesinger commented that as a citizen he's not really enthusiastic about "finding more ways or faster ways to teach our soldiers to kill people," but would rather more effort be put into teaching soldiers and politicians "to learn to talk to people and to make peaceful decisions…" Mr. Webb acknowledged Mr. Schlesinger's comment, but noted that he doesn't think this meeting is the right forum for that discussion. He also said that when looking forward to the possibility of using lead ammunition again, it would make sense to think about how to create shooting ranges in such a way that lead does not become an issue. Mr. Webb noted that he agrees that training is important, but also believes that there has to be a way to create ranges that alleviate the concern of lead leaching into groundwater. Mr. Schlesinger questioned why Mr. Webb's opinion was any more appropriate for the IART forum than his own, but Mr. Webb recommended continuing the discussion outside of the meeting. Mr. Mullennix noted that the IART is a citizens group that's concerned about environmental affairs at the MMR, and not about anything beyond that. Agenda Item #8. Adjourn Mr. Murphy noted that the IART would meet next on April 25, 2006 at the Best Western Hotel in Bourne. He then adjourned the meeting at 9:00 p.m. |
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| Administrative Notice |
