Determining Scope and Degree of Lost Lake Watershed Environmental Problems
In their effort to determine the scope and degree of potential contamination in the immediate Lost Lake area, and its surrounding watershed, the Lost Lake Sewer Committee invited Dan Wolfe, President of the civil engineering firm, David E. Ross Associates, to provide his assessment of what is working at the lake and what he looks at when planning and designing septic systems and wells for this area. David E. Ross Associates has extensive experience working on residences at Lost Lake, the firm working with homeowners as well as large commercial property owners.
In addressing implications of the large number of older systems at Lost Lake, Wolfe stated that many older systems may be directly in the groundwater and that these are likely the largest contributors to any groundwater problem around the lake. However, he noted that 'overzealous' regulation imposed by area towns in the past created a disincentive for people to work with their towns to improve their systems, adding that people are afraid of the BOH, ZBA and Conservation Commission.
Despite fear of the town bureaucracies, Wolfe disagreed with a finding of CEI consultants regarding the inventory of older systems at the lake, saying that there had been many more repairs/replacements than indicated. He said that records at Ross Associates alone show more upgraded systems than indicated in the CEI Report and that Ross is only one of many firms that do such work in the area.
He acknowledged that the Lost Lake area of town is challenging due to soil types and lot size, but said his firm has been able to develop successful designs for homeowners needing new septic systems. "It is not difficult to design and balance within the rules. The Board of Health and the Nashoba Associated Boards of Health have rules that are great for planning,"
Among many possible solutions, the 'Presby' system is a highly regarded having installed several in the lake area as well as other locations, he noted. These are compact systems requiring less space than traditional septic systems.
When working with clients it is his intention to present the best combinations, and "navigate the dimensional issues. To be totally compliant with Title V you need variances for such areas as offset to the road line."
Wolfe stressed that the offset from a septic system to a well is more difficult when you don't have the ability to keep the septic system 100 feet from the well. If you can only design for 80 feet from a well, the State allows the designer to present this to the permitting authorities. When that span is down to 50 feet, there is a real concern that this could pollute the well and many homeowners may test their wells yearly because of this smaller separation.
When options are few and compromises are many, the next move is to a tight tank, which is much more expensive as it needs continual pumping. The bottom line for Wolfe is, "I don't want (the septic system) less than 100 feet from the well."
Committee Chairman Jack Petropoulos asked about the definition of a failed well. Wolfe told him that in Groton, every well needs to have a water test for every real estate transfer. "The concern for the wells is only a portion of the issue ...you need to know what is happening with the ground water." The majority of the lake has coarse sand and gravel, and the dispersal of the effluent goes through this type of soil very quickly. The systems we propose treat the effluent, which is a cleansing action." Title V does have some regulations for such soils that drain quickly and they need to be an extra foot above ground water level.
Committee member and Board of Health member Dr. Susan Horowitz pointed out that the coarse sand can't act as a bio mat that gives the water moving through it time to cleanse. Wolfe acknowledged that there is a correlation between the water in the lake and septic systems "but we can't tell how much and we don't know the leading cause."
Areas of concern and questions for the Committee revolved around "emerging contaminants," things like ingested medications that can only find their way into the lake through septic systems. Member Jay Prager pointed out that these "emerging contaminants" are measured in PPT (Parts Per Trillion) adding that the issue is whether or not they are contaminating the lake.
Prager raised a second issue - that of phosphorous in the lake in which a recent study showed that levels were about the same as those detected in a 1989 study...and could be a result of the Martins Pond Brook runoff. Groton Water Department Manager Tom Orcutt added that the only source of phosphates would come from use of fertilizer as phosphates were banned from use in laundry soap.
According to Wolfe, there are a number of alternative systems that can provide treatment of nitrates and other pollutants, some that have higher maintenance than others due to the mechanical components. In addition to the maintenance issues, there is concern about the effect power outages have on mechanical systems in terms of operation.