February 28, 2007
Ms. Sonal Gandhi
Boston Redevelopment Authority
One City Hall Square
Boston, MA 02201-1007
Subject: Dana Farber Cancer Institute
Dear Ms. Gandhi:
Thank you for the opportunity to comment on the Institutional Master Plan/Draft Project Impact Report for DFCI.
The Boston Groundwater Trust was established by the Boston City Council to monitor groundwater levels in sections of the City where building foundations are threatened by reduced groundwater levels and to make recommendations for solving the problem. As such, my comments are restricted to groundwater related issues.
Although the project site is located outside the Groundwater Conservation Overlay District, which ends one block away at Longwood Avenue, I was pleased that the proponent chose to reach out to the Trust to discuss their foundation design and how it might affect groundwater levels.
The building site is located on original land at approximately Elevation 40 BCB. There are unlikely to be any wood piling supported buildings in the immediate vicinity. The foundation has been designed with slurry walls that will extend into the bedrock, intended to provide an effective cutoff to groundwater flows. While there will be an underdrain system, the cutoff will likely assure that any groundwater to be drained will be that which seeps through the bedrock and is not expected to affect groundwater levels in the fill stratum that is critical to preservation of wood pilings.
It will still be useful to monitor groundwater levels before and during construction to make sure that the integrity of the slurry walls is adequate to accomplish their purpose. The wells should be turned over to the Trust or, if on private property, access should be granted, so that we can continue to monitor them after the project is complete.
I look forward to working to with the proponent and the Authority to determine the location of any new wells and to help to assure that the project cannot have any negative impact on critical groundwater levels.
Very truly yours,
Elliott Laffer
Executive Director
Cc: Maura Zlody, BED
