Until relatively recently, technology for the onsite treatment of household sanitary waste in Massachusetts was relatively “standard” , involving in most cases a septic tank for the settling of solids and mineralization of wastes, and a leachfield for the safe disposal of the liquefied waste in appropriate locations away from points of possible human exposure. A frank assessment of this technology is that its primary focus is on disposal, following some rudimentary treatment. Ultimate “treatment” in standard systems is primarily due to dilution, dispersion and retention in underlying soils until pathogens are rendered harmless. The lack of focus on actual treatment of waste onsite is primarily attributable to the thought that the onsite septic system was a temporary means of waste disposal until such time as the community constructed centralized sewage treatment facilities. With the withdrawal of federal support for centralized wastewater collection and treatment facilities and the economic realities associated with such, communities now recognize that the onsite septic system is evolving into the long-term wastewater solution for many areas. The problem generally recognized under the paradigm of onsite septic system use is that research continues to verify that certain resource areas, such as drinking water aquifers and watersheds of marine and freshwater resources, can no longer tolerate the mere disposal of wastes. Many communities are now inquiring as to what options are available to actually treat wastewater for harmful constituents near their source of generation – onsite. Until recently, however, options for the widespread use of “alternative” onsite septic systems were fairly limited.
In March, 1995, the landscape of alternative septic system use in Massachusetts was dramatically changed. Up to this point, alternative methods for disposing of sanitary waste onsite were generally rare; most installations involved composting toilet technology that was allowed at the time. The March, 1995 changes to the onsite septic system regulations in Massachusetts (CMR 15.00, commonly referred to as Title 5) however, describes the various approval processes for more widespread use of alternative onsite septic system technologies. These past two years have witnessed both a clarification of the permitting process and a proliferation of the technologies statewide.
The quest for the better “mousetrap” in onsite septic system technology in Massachusetts began in the early 1990′s. In February, 1992, the Waquoit Bay National Estuary Research Reserve (WBNERR) sponsored the first conference on alternative onsite septic system (AOSS) technology to be held in Barnstable County. As participants heard of the various states’ programs for alternative septic system use, many wondered what was preventing their use in Massachusetts. These questions were somewhat answered, however, as the stories from various states revealed the two-edged-sword nature of alternative septic systems. On the one side, AOSS can address both limiting physical conditions (soil percolation rate or distance to groundwater, space, etc.) and pollution problems (nitrogen in particular). On the other side AOSS technology could, without adequate planning controls, open up new areas to development that were otherwise restricted in part by then-present Title 5 constraints.
Nevertheless, 1993-1997 has witnessed a number of research and demonstration projects to demonstrate the efficacy of AOSS technologies. A particular aspect of AOSS introduction to Massachusetts at this point bears mention. In many other parts of the country, AOSS were introduced primarily to address the issue of poorly-percolating or otherwise limiting soil conditions as opposed to addressing the various nonpoint pollution issues of onsite septic system use. Many USEPA studies focusing on marine and estuarine water quality (including two in Massachusetts – the Buzzards Bay Project and the Massachusetts Bays Project), however, confirm the need to address the issues of nitrogen and pathogen contribution to marine systems from onsite septic systems. Accordingly, the focus of most of the demonstration projects in Massachusetts has been to demonstrate the reduction of both pathogens and nitrogen.
The first demonstration project in Massachusetts for AOSS continues until today in the City of Gloucester. Faced with the pressure to expand their sewage treatment facility, city officials there sought to demonstrate that onsite solutions were feasible both from the treatment aspects, as well as economically. Since then, demonstration projects have proceeded under support from the Massachusetts Department of Environmental Protection (under the 319(b) Program – four systems are being installed between the towns of Provincetown, Eastham, Wellfleet, and Truro), the Massachusetts Bays Program (five systems have been installed in Wellfleet under the MiniBays subprogram), the Buzzards Bay Program (two systems have been installed in that watershed, with one more soon to be installed), and WBNERR (four different technologies have been installed and are being monitored under the National Onsite Demonstration Program of EPA). In addition, a cooperative project between the Barnstable County Department of Health and the Environment, Dr. Brian Howes of the Center for Marine Science and Technology (CMAST) of the University of Massachusetts at Dartmouth, and the Buzzards Bay Project, endeavors to construct an AOSS technology testing facility under a program called Environmental Technology Initiative (ETI). The testing facility is to be constructed at the Massachusetts Military Reservation.
If you have been a regular reader of the newsletter from which this document is derived, you will notice that the following chapters do not, for the purpose of logical presentation of the information, contain the following two “warnings”, which were sporadically echoed in the newsletter. The first warning relates to the fact that, although often not officially stated, Title 5 has in the past been used as a de facto density control. As AOSS develops, municipalities should heed the “heads up” that should have already been heard. If proper planning instruments are not in place to articulate what a community wants to be (i.e. what densities of residential housing it desires or can support), it is quite possible that the advancing technologies will allow higher density of development than communities might desire. Already, relating to the issue of nitrogen loading, proponents wishing to develop at higher density can obtain “credits” for doing so by using AOSS (see chapter on permitting). The second “warning” is more specific to Boards of Health and other individuals who are applying AOSS technology. The caution here is merely to understand the technology before applying it to a specific problem. The most common misapplication of AOSS we have seen is the situation where a Board of Health allows the installation of AOSS to compensate for the inability of a proponent to meet a setback requirement of 100 feet from a watercourse. In these instances we have seen denitrifying technologies allowed to compensate for a setback that was predicated on pathogen (specifically virus) concerns. In short, unless the technology being proposed addresses the issue that is central to your setback requirement, it should not be considered a compensating action by the proponent.
In closing to this introduction, the authors would again like to remind the reader that this compendium is not the “final word” on AOSS. Through various funding supports, the Barnstable County Department of Health and the Environment intends to continue to produce the newsletter from which this document was derived. In the next year, support is provided in part by the Massachusetts Bays Project, and the Department of Environmental Protection through a 319(b) grant to our Department. The authors again wish to express thanks to all those individuals, notably the staff of DEP Division of Wastewater Management who continue to contribute to the accuracy of the documents.