The Carlisle Mosquito Online

Friday, October 6, 2006


ConsCom takes on one challenge, closes out another

The Conservation Commission spent a major portion of its September 28 meeting studying engineering specifications for what promises to be a challenging construction site behind the former home of Doris and Niels Larsen on Concord Street. Stamski and McNary engineer George Dimakarakos presented a working version of his proposal for the Larsens' Notice of Intent to build a single-family dwelling with a 900-foot driveway that must cross a Bordering Vegetated Wetland (BVW). The crossing will require 2,754 square feet of wetland fill and hence 3,663 square feet of wetland replication. The engineer says the replacement area will be designed to provide "unrestricted hydraulic connection" with the wetland itself, and will be vegetated with native plants. Finally, the crossing calls for an oversized culvert to preserve drainage within the system as a whole.

Since there is a 25-foot elevation from Concord Road to the dwelling, drainage from the driveway will be directed away from the BVW into a grass swale, with a second rip rap (rock-lined) swale downstream of a "sedimentary pump." To minimize clearing and grading of the heavily wooded lot and to provide a permanent barrier to indicate the limits of the yard, Dimakarakos calls for substantial retaining walls between the house and the BVW.

Complicating matters further, there is a documented vernal pool associated with the wetland, and commissioners who have seen the feature say that it is no ordinary vernal pool. Its dimensions (1,080 feet by 375 feet) and its clearly defined bank have led to an official state designation of the system as "outstanding resource water." The project's peer reviewer, Dr. John Rockwood, has described the pool as "the second nicest vernal pool I've seen in all my years of experience." This expert evaluation has caused the state Department of Environmental Protection to send out three representatives and stress the need for a thorough Wildlife Habitat Assessment.

Fields hearing closed.

As the Larsen project took center stage, the long-fought Edward and Linda Fields hearing was closed for the second time. That application had called for construction of a single-family dwelling, septic system and driveway in a Riverfront Area off Bedford Road associated with Pages Brook and the 100-foot buffer zone of a Bordering Vegetated Wetland. The couple's engineer Dimakarakos had presented this "preferred plan" plus two alternatives that would not have required work within the restricted riverfront, but both of which he said would impose significant economic hardship. His argument rested on a clause in the state Rivers Act that permits a 10% incursion into the riverfront if the applicant can prove that use of any alternative plan would entail sufficient additional cost.

The commission at first questioned the validity of the cost estimates, particularly the projected need for a fire cistern at the alternate sites. When that cost was later confirmed and the economic hardship accepted by the commissioners, the hearing was closed, only to be reopened when the requirement for a sprinkler system at the preferred location complicated the situation.

At the September 28 session, a revised cost analysis was approved and the hearing closed for a second time, with a statement that the conditions that had caused the reopening had now been satisfied. Drafting of the Order of Conditions that will guide implementation of the project will be completed and reviewed at the next meeting. The commissioners also voted to add the following "finding" to that Order: "Our decision is based on an alternate analysis that makes the assumption that a sprinkler system will be installed."

2006 The Carlisle Mosquito