The Carlisle Mosquito Online

Friday, May 31, 2002


Shorts from the board of health, May 21

· 106 Concord Street. Homeowner Christoph Karpeter of 106 Concord Street appeared at the board of health to request a construction permit for his alternative septic system. Back in September the board of health approved the system with three waivers, but it has taken until April 17 for the planning board, conservation commission and state department of environmental protection (DEP) to approve the system. All of these steps were necessary before the board of health could issue the construction permit.

The system, which is designed by Sustainable Strategies, in West Concord is an alternative to the mounded system for repair of a failed septic system. The design requires using composting toilets and a 2,000-gallon tight septic tank-greenhouse combination to absorb filtered gray water. Gray water is water from showers, washing machines, dishwashers and sinks. One-third of the septic tank is used to collect gray water which is used to periodically spray thirsty non-edible plants in an adjacent greenhouse with a pressure dose.

The board asked about the cost of a conventional system and was told that a conventional system would be a tight fit and would require an expensive retaining wall. The costs were estimated to be $60,000 for either system. Members of the board questioned the time frame for installation. The DEP requires in Title 5 that a failed system be replaced within two years, but the DEP had just approved the system. Board agent Linda Fantasia suggested one year from the DEP approval date of April 17 would be reasonable. The board agreed to this date with the requirements that the Karpeters get a deed restriction for four bedrooms, report progress quarterly and install two water meters for flow measurements.

· 331 East Riding Drive. The board approved a waiver to replace and extend a deck which would place three sonotube supports five feet from the septic tanks. The installation has two tanks and one support would be five feet from one tank, and two of the other supports five feet from the other tank. Carlisle's requirement is that building structures be at least ten feet from a septic tank. The board granted the waiver with the restriction that the support tubes be hand-dug. Fantasia will prepare a letter for the building inspector explaining the board's action.

· 985 North Road. Homeowner Minzi Ruan brought her engineer Tom Di Persio to explain his calculations of flow in the septic system. Ruan wants to complete an expansion adding three rooms over the garage as a residence for her parents.

Di Persio outlined the tests run to attempt to expand the existing 1980-built septic system, showing that in each direction expansion was inhibited by ledge. An additional space on the other side of the garage did not show any area suitable for a soil absorption system.

Calculating the flow capacity of the current system using the perc rates on the plan and the Title 5 loading rates, Di Persio came to a 710-gallon flow rate. Board of health consulting engineer Rob Frado confirmed the calculations. This will provide a six-bedroom septic system if the house does not contain a garbage grinder or a four-bedroom system if the garbage grinder is permitted. Fantasia pointed out that the plan explicitly says that there will be no garbage grinder.

The board then turned to the matter of the bedroom count. In the initial count there were 14 rooms, which by today's rules would mean a seven-bedroom septic system must be used. However, on more careful scrutiny, it was decided that the kitchen and small eating area could be counted as only one room bringing the room count down to 13. By the board's rules the septic size is determined by the room count divided by two, rounded down, and thus a six-bedroom septic system would meet the needs of the expanded house and no variance would be required.

Board member Lisa Davis Lewis requested that the homeowner install a water meter to measure the flow before and after the expansion.

· 125 Meadowbrook Road. The board was informed that the guest house design at 125 Meadowbrook Road was on hold because the board of appeals discovered a 1984 rule which prohibits a cooking facility in a guest house. As far as the board of health is concerned, the design of the eight-bedroom septic system met with the board's approval and would be in the best interest for public health if used to replace the current system if it fails.

2002 The Carlisle Mosquito