Meeting Minutes

Agenda Item 1. Introduction

Ms. Musgrave convened the meeting at 6:35 PM. She explained that the purpose of this meeting is to discuss the proposed drilling on Ashumet Pond and Johns Pond. She noted that conceptual ideas will be presented tonight and the specifics are expected soon. Ms. Musgrave introduced Mr. Pannell from Jacobs Engineering.

Agenda Item 2. On Pond Presentation

Mr. Pannell reiterated that this is an informational meeting to discuss the proposed program and investigation on Ashumet Pond and Johns Pond. He stated that the workplan is currently under review by the regulatory agencies.

Mr. Pannell reported that the on-pond drilling has been broken into three phases. Phase I includes the trichloroethylene (TCE) plume beneath Ashumet Pond, Phase II includes the Chemical Spill 10 (CS-10) plume beneath Ashumet Pond, and Phase III includes the Storm Drain 5 South (SD-5 South) plume that is discharging into Johns Pond.

Mr. Pannell displayed a map of the SD-5 South plume and noted that there is a break in the plume just south of the SD-5 North treatment system. He then identified the TCE plume, which was discovered last year and noted that it was further investigated this past winter. He also identified the location of the CS-10 plume and stated that it originates near the Unit Training Equipment Site (UTES)/Boeing Michigan Aeronautical Research Center (BOMARC) facility.

Mr. Pannell reported that the TCE plume was discovered in August 1998 by the United States Geologic Survey (USGS), while it was conducting vapor diffusion sampling in Johns Pond in an attempt to delineate the footprint of the SD-5 South upwelling. He stated that from November 1998 to January 1999, the TCE plume was further characterized using a combination of vapor diffusion sampling conducted by the USGS, and direct-push sampling conducted by Jacobs Engineering. Mr. Pannell reported that 24 direct-push holes have been completed on the pond and on the isthmus between the ponds. He described the direct-push method, and noted that it can reach depths of 100 feet below ground surface. He reported that groundwater samples were collected every ten feet in order to help delineate the footprint of the TCE plume. Mr. Pannell stated that, based on the information collected from the direct-push effort, it was determined that sonic drilling would be required to reach greater depths at Hooppole Road and at Wheeler Road. He explained that the sonic drilling allows deep groundwater samples to be collected and also provides soil cores. Based upon the information collected from the direct-push effort and the sonic drilling, it has been determined that there is no additional plume beneath the TCE plume.

Mr. Pannell noted that based upon the information in the profile, all of the TCE plume discharges into Johns Pond. He displayed a cross-section of the TCE plume and identified Ashumet Pond, Johns Pond, the two sonic holes, and the direct-push holes. He reported that the highest concentration of TCE detected was 1677 parts per billion (ppb), and the highest concentration of tetrachloroethylene (PCE) detected was 6 ppb. Mr. Pannell noted that the drinking water standard for both TCE and PCE is 5 ppb. He also reported that there were low trace concentrations of other chlorinated solvents, most of which are breakdown products of TCE.

Mr. Pannell reported that at two locations underneath Johns Pond, the drilling went through the TCE plume and reached the top of what is believed to be the SD-5 South plume. It is believed that the SD-5 South plume was reached because there were decreasing concentrations, approaching or reaching nondetect, and then, at the very bottom, samples increased in concentration. He also reported that there were detections of ethylene dibromide (EDB), which is not a constituent of the TCE plume, but is present in the SD-5 South plume.

TCE plume

Mr. Pannell reported that groundwater modeling suggests that the TCE plume is an extension of the CS-10 plume. Investigations on Johns Pond are needed in order to prove that suggestion. Mr. Pannell displayed a map that shows the proposed area of the TCE plume investigation, also known as Phase I. He explained that the plan is to start at the east side of Ashumet Pond and move back across the pond toward the north, using the direct-push method to locate the plume laterally. He reported that sonic drilling will be done to reach deeper depths at specific locations; those locations will be chosen based on the results of the direct-push effort. Mr. Pannell also reported that deeper groundwater samples and soil samples will be taken in order to provide an understanding of the geologic controls of plume migration. He stated that this information is critical to understanding what might be coming in future years.

CS-10

Mr. Pannell displayed a map and identified the Phase II proposed area of the CS-10 plume investigation. He identified the source of the CS-10 plume and noted that it is also receiving contribution from other sources across the middle portion of the base. He identified the location of the Sandwich Road extraction fence and the location where the in-plume system will be installed. Mr. Pannell stated that there is a component of CS-10 that is downgradient of Sandwich Road and will not be captured by this treatment system. If the model is correct, and the TCE plume is in fact connected to the CS-10 plume, then other manifestations of CS-10 should be sought in this area of investigation under Ashumet Pond.

Mr. Pannell reported that Phase II will begin with USGS vapor diffusion sampling to determine where the CS-10 plume may be upwelling into Ashumet Pond. The results of that sampling event will help focus the drilling program, which will include direct-push sampling followed by sonic drilling at selected locations. Mr. Pannell stated that Phase II is expected to begin immediately upon completion of the TCE plume investigation.

Mr. Pannell mentioned that an investigation related to the phosphorus plume will be occurring simultaneously. He noted that a public meeting on the phosphorus investigation is scheduled for May 11, 1999. Mr. Pannell reported that the phosphorus investigation will include additional drilling, most of which will be direct-push. The drilling will occur mainly around the perimeter of the ponds.

SD-5 South plume

Mr. Pannell displayed a map and identified the Phase III proposed area of investigation for SD-5 South. He identified the location of the SD-5 North treatment system and again noted the break in the plume downgradient of that treatment system. He also identified the locations of the two recirculating wells that are currently being installed. Mr. Pannell stated that last year a number of wells were installed in Johns Pond using the direct-push method. He displayed a cross section of Johns Pond, which showed the SD-5 South plume discharging into Johns Pond. He reported that based upon the field data, the groundwater model, and the absence of plume constituents in monitoring wells downgradient of Johns Pond, it is believed that most or all of the SD-5 South plume is discharging into Johns Pond. He noted that previous on-pond drilling was unable to penetrate the silty-sand area except at one location on the pond, therefore, there is no certainty regarding the absence of these contaminants.

Mr. Pannell reported that the Air Force Center for Environmental Excellence (AFCEE) is proposing to drill three additional deep sonic borings on Johns Pond. He displayed a map of the proposed area of investigation on Johns Pond and stated that the three locations would likely be in the area downgradient of the SD-5 South upwelling. He explained that this work will allow for the collection of geologic samples that could not be collected with the drilling techniques used last summer. The geologic samples will provide information regarding whether there is a geologic control on plume migration. Mr. Pannell stated that groundwater screening samples will also be collected at ten foot intervals, which will help determine whether there is a component of the plume underflowing the pond.

Mr. Pannell summarized that Phase I includes direct-push and sonic drilling on Ashumet Pond, related to the TCE plume; Phase II includes direct-push and sonic drilling on Ashumet Pond, related to the CS-10 plume; and Phase III includes sonic drilling on Johns Pond, related to the SD-5 South plume.

Schedule

Mr. Pannell reported that, assuming that approval from the regulatory agencies is granted, Phase I will begin in mid to late May, and will take a few months, Phase II will begin immediately after completion of Phase I, and is expected to carry through the summer and possibly into the fall; and Phase III is scheduled to begin after Labor Day.

Impacts to the community

Mr. Pannell listed actions that will be taken in order to minimize any impacts on the neighborhoods: (1) drilling will occur on one pond at a time, (2) Johns Pond drilling is scheduled after Labor Day, (3) the direct-push method, which is the fastest and quietest method available, will be used, (4) caution signs will be posted at the boat ramps and beach access areas on Johns Pond and Ashumet Pond, warning users about the presence of the rig on the water, the buoys, the anchor lines, and soforth. (He displayed a slide of a sample posting), and (5) operation will occur from 8:00 AM to 6:00 PM, Monday through Friday and from 8:00 AM to 4:30 PM on those Saturdays when work will need to be done. He noted that 30 minutes is allotted before work begins and after work ends, to setup and breakdown equipment. He also noted that work will not be done on Sundays.

Agenda Item 3. Public Comment, Questions and Answers

Mr. Dow commented that the phosphorus plume is associated with the Ashumet Valley plume, which is located more to the south. He then asked why the phosphorus plume investigation is taking place in the boundary between Ashumet Pond and Johns Pond.

Mr. Blount, from Jacobs Engineering, agreed that the phosphorus plume study is associated with the Ashumet Valley plume. He explained that the phosphorus study is a separate study, although, at times there will be overlap. Mr. Blount stated that part of the Ashumet Valley plume discharges into Ashumet Pond and there is a concern that there is phosphorus in Ashumet Pond that is affecting its ecology. He stated that the phosphorus investigation is intended to characterize the impact of the phosphorus from the old sewage treatment plant on Ashumet Pond, to gather information on the impact to the ecology, to determine where and if the phosphorus is accumulating, and to evaluate whether or not remediation efforts are warranted.

Mr. Dow commented that if the phosphorus study is going to occur simultaneously with Phase I and Phase II, it will go on into the summer, and it appears that most of the phosphorus plume work will be done where people either fish or swim. He then asked how conflicts with the recreational usage of the pond will be avoided. Mr. Blount replied that Jacobs Engineering is working with the Massachusetts Division of Fisheries and Wildlife (MDFW) to ensure that its guidelines are met. He commented that he did not foresee this level of work as being intrusive. He explained that a small barge will be used, the majority of the drilling will be the direct-push method, and grab sampling will be done from a boat. He stated that this effort will not take up a lot of space on the pond.

Mr. Miller noted that the phosphorus program will be discussed at the May 11, 1999 community meeting. He commented that this meeting is specifically focused on the on-pond drilling for CS-10 and SD-5.

Mr. Dow expressed concern about a combined impact with the investigations occurring simultaneously. Mr. Pannell stated that he has been in communication with Mr. Steve Hurley from the MDFW, who has provided Jacobs Engineering with a list of scheduled activities on Ashumet Pond.

Mr. Fribush asked where the highest levels of PCE (6 ppb) were detected. He also asked what was found at the one location where deep drilling was done last year on Johns Pond. Mr. Pannell replied that the highest concentration of PCE was detected at location 615, approximately 50 feet offshore in Johns Pond. He noted that this is the location where the highest concentrations of plume constituents were detected discharging into the pond. He stated that the highest detection of TCE (1677 ppb) was detected "here." Mr. Pannell replied in response to Mr. Fribush’s second question, that there was an area of maximum upwelling "here" and there were levels of TCE detected at 40 ppb. He stated that the SD-5 South plume has TCE levels up to about 60 ppb, which is significantly less than what is seen in the TCE plume.

Mr. Wires asked if the dark red area on the map indicates PCE. Mr. Pannell replied that it indicates TCE concentrations. Mr. Wires commented that the diagram shows that the TCE comes right to the bottom of the pond itself. Mr. Pannell replied that this is correct. Mr. Wires then asked if the concentrations of TCE are 1500 ppb. Mr. Pannell replied that when he says 1677 ppb "here" and 1500 ppb "here," it is an artifact of sampling. He explained that if he had sampled three feet, one way or the other, concentrations would be different. Mr. Pannell commented that the TCE plume is highly concentrated and very compact; it is only 50 feet wide at Ashumet Pond and 75 feet wide at Johns Pond. He stated that the concentrations range from non-detect to 1000 ppb, in less than 25 feet, both vertically and laterally. Mr. Wires asked if Mr. Pannell was indicating that the highly concentrated TCE plume presently mixes with the water and is diluting. Mr. Pannell replied that this is correct. He also said that surface water samples were collected directly above where maximum concentrations are discharging into the pond. He explained that the samples were collected at several intervals ranging from two inches to four feet above the top of the sediment and the results indicate that TCE is detectable in the surface water samples up to about 3.5 ppb. He noted that the drinking water standard is 5 ppb. Mr. Pannell reported that the 3.5 ppb was detected about six inches above the top of the sediment. He stated that the concentrations detected at one foot above the top of the sediment were less than 1 ppb, and at three feet, the samples were non-detect. He explained that there is a lot of dilution occurring.

Ms. Greene asked why the drilling is scheduled to occur on one pond at a time. Mr. Pannell replied that the logistics of mounting the sonic drill are immense and there is not enough time between May and July 4, 1999. Therefore, rather than impact the recreational season, or go through a massive mobilization effort and then have to undo it, it was decided to drill on one pond at a time. Ms. Greene commented that she would rather "get this cleaned up" even if it means being inconvenienced for one summer. She commented that she has neighbors that are incurring a great expense to install pools because they will not have their children swimming in the ponds for extended periods of time this summer. Mr. Pannell asked if there was anyone present from the Board of Health who could address what the concentrations mean in regard to recreational users. He stated that AFCEE collects samples, and AFCEE funds the local Boards of Health to collect samples in the pond. He reported that to date the only place a plume constituent has been seen, is in "this" area of investigation.

Mr. Minior commented that there is another aspect of the cleanup project. He explained that a project is currently being designed to install a treatment system on Hooppole Road to capture the TCE and the portion of the SD-5 South plume that is still moving forward. He stated that the plan is to begin construction after Labor Day and get the system up and running in the January, February 2000 time frame. This system will pull all that material in, and the small amount that is inbetween the system and the pond would flush out in a very short period of time. He commented that there will be a very short-term impact.

Ms. Musgrave added that all of the data collected by AFCEE is shared with the local, state, and federal health departments, which are currently reviewing the most recent data. She also stated that for the past two years there has been a fact sheet about the recreational uses of different ponds around the Massachusetts Military Reservation (MMR). The health departments will be updating that fact sheet based on AFCEE’s most recent data. Ms. Musgrave also stated that AFCEE, working with state and federal environmental agencies, as well as with the health departments, will be attempting to address the type of comments being made tonight. She stated that fact sheets are being developed, which will be made available to new residents who can then choose which parts of the ponds they want to use.

Mr. Dow asked if there was a plan to sample the fish in Johns Pond or Ashumet Pond, for TCE or PCE, before the summer recreational season begins. Mr. Minior replied that there is an interest in collecting that data before the end of May 1999. He stated that AFCEE, working with the Mashpee Board of Health, will attempt to accomplish that sampling, for which AFCEE is willing to fund.

Mr. Dow asked if there are plans to also sample the water in relation to the people swimming in the pond. Mr. Minior replied that today an agreement was delivered to the Board of Health, and AFCEE has agreed to pay for the recreational pond sampling, as it did last year and the year before. Mr. Dow asked if it is correct that the sampling occurred in July 1998, and added that he thinks it is late to sample in July for a fact sheet to be out before July 4. 1999. Mr. Minior clarified that he was referring to the Board of Health sampling starting just before Memorial Day and extending through Labor Day. This sampling will be done on a bi-weekly basis to ensure that the water quality is safe. Mr. Dow asked if it is correct that in addition to that fact sheet, there will be bi-weekly sampling, the results of which the town will publish for residents, both on fish and water levels of TCE in both ponds. Mr. Minior replied that the town will be taking those samples and will probably publish those results as needed. He said that while he cannot speak for Mr. Elias McQuaid, for the last three to four years AFCEE has been working with the Mashpee Board of Health to provide that information to the town. Mr. Minior stated that AFCEE has paid for that sampling so the town would not incur the cost, as it has done in the past.

Mr. Fribush asked if it is correct that the TCE is coming in at 1400 ppb at the bottom of the pond, and those levels are down to 3 ppb at the top of the pond. Mr. Pannell clarified that the SD-5 South plume has levels of about 60 ppb up "here." Mr. Fribush asked what exactly is coming into the water. Mr. Pannell replied that 40 ppb, which is related to SD-5 South is coming into the pond. Mr. Fribush asked if 5 ppb is considered a health risk. Mr. Pannell clarified that the drinking water standard is 5 ppb; one would not want to drink the groundwater that is discharging into Johns Pond at that location because it contains more than 5 ppb. He stated that the surface water in the pond is non-detect. Mr. Pannell reported that numerous surface water samples have been collected and because of the dilution effect, a plume constituent associated with SD-5 has never been seen in the surface water.

Mr. Minior stated that the 40 ppb, to which Mr. Pannell referred, is located below the bottom of the pond in the sediment. Also, the 1400 ppb, to which Mr. Pannell referred, is below the bottom of the pond in the sediment. He reported that concentrations detected a few inches above the bottom of the pond are 3 ppb; the concentrations detected at three feet above the bottom of the pond are non-detect. Mr. Minior stated that the concentrations being seen in the water are technically safe to drink, but there are higher concentration areas in the sediments underneath the pond.

Mr. Fribush asked if the concentrations could spread on the bottom. Mr. Pannell replied that he did not think they could. He then displayed a slide that showed all of the surface water sampling locations done in February. He stated that some of those locations will be re-sampled the first week in May. Mr. Pannell identified the SD-5 south upwelling and noted the location of non-detect. He then identified the TCE plume and the location where the high concentrations are discharging into the pond. He noted that up to 3.5 ppb is seen in the surface water. He commented, however, that on either side of that location it is nondetect. He explained that the layer of 3.5 ppb is not spreading out, rather it is becoming so dilute that it is not detectable.

Mr. Fribush asked when results from the proposed drilling on Johns Pond will be back. Mr. Pannell replied that results are presented to the regulatory agencies every Thursday morning. Mr. Minior added that if there is something of concern, the Air Force, the MDPH, the town, and the Board of Health will decide what, if any, announcement is necessary, in regard to whether the community needs to be notified. He stated that if something is found that is typical to what has been found before, and it does not present a threat or risk to public health, the data is held and will be included in the report that will be developed upon completion of the investigation. Mr. Minior stated that the regulatory agencies receive results on Thursday mornings, at which time a determination is made as to whether or not there is a concern and what the next steps should be.

Mr. Dow asked if input on this plan would be solicited from the Joint Process Action Team (JPAT) before Phase I begins. Mr. Pannell replied that this proposed drilling will be discussed at the next JPAT meeting. Mr. Dow asked if the JPAT members will have an opportunity to comment on the plan before it is finalized with the regulators. Ms. Musgrave replied that they will. Mr. Minior added that there have been preliminary discussions with the JPAT members at previous meetings in March and February. The presentation at the next JPAT meeting will be a further clarification of the process.

Agenda Item 4. Adjourn

Ms. Musgrave welcomed the attendees to review the posterboards and noted that personnel from AFCEE, Jacobs Engineering, and the regulatory agencies will be available to answer any additional questions the attendees may have.

The meeting adjourned at 7:15 PM.