February 29, 2008
Mr. Tai Lim, Economic Development
Boston Redevelopment Authority
One City Hall Square
Boston, MA 02201-1007
Subject: Parcel 24 Chinatown
Dear Mr. Lim:
Thank you for the opportunity to comment on the Project Notification Form for Parcel 24. The Boston Groundwater Trust was established by the Boston City Council to monitor groundwater levels in sections of the City where the integrity of building foundations is threatened by low groundwater levels and to make recommendations for solving the problem. As such, my comments are limited to groundwater related issues.
I am very pleased with the statement, in Section 4.9.1 of the PNF, that the project will comply with the requirements of the Groundwater Conservation Overlay District. Even more encouraging is the attempt, articulated in Section 3.3, to achieve 50% more recharge than required under Article 32.
Also required under the GCOD is a certification by an engineered registered in Massachusetts that the project cannot cause a reduction in groundwater levels on the site or on adjacent lots. Because the PNF indicates that the excavation for the below-grade portion of the structure may extend up to 10 feet below the site groundwater level, it is important that the DPIR addresses how the reduction in groundwater levels will be avoided both during construction and operation of the project.
The PNF uses elevations against an unspecified base; all elevations should be measured against Boston City Base for consistency with the zoning regulations and with the groundwater level measurements posted by the Trust.
The Trust currently maintains two groundwater observation wells along Hudson Street across from the project site. Because of the length of the project site, it would be useful for the project to install at least two additional observation wells at locations chosen in consultation with the Trust. These should be built to Trust specifications in the public way, and should be turned over to the Trust after construction to become part of our monitoring network. These wells, as well as the two existing wells, should be monitored by the project before and during construction, with results reported to both the BRA and the Trust, to make sure that the project meets its commitment to not cause a reduction in levels.
The concern about groundwater issues shown by the proponents both in the PNF and in the BRA scoping session is very encouraging. I look forward to working with them and with the Authority to assure that this project can have only a positive impact on area groundwater levels.
Very truly yours,
Elliott Laffer
Executive Director
Cc: Kathleen Pederson, BRA
Maura Zlody, BED
