May 1, 2007
Mr. Jay Rourke, Project Manager
Boston Redevelopment Authority
One City Hall Square
Boston, MA 02201-1007
Subject: GrandMarc at St. Botolph Street
Dear Mr. Rourke:
Thank you for the opportunity to comment on the Project Notification Form for the GrandMarc project. 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 lowered groundwater levels and to make recommendations for solving the problem. As such, my comments are limited to groundwater related issues.
As acknowledged in the PNF, the project site is located within the Groundwater Conservation Overlay District. However, the document includes a mistaken interpretation of Article 32. Whether or not the project includes construction below Elevation 7 BCB, it will trigger the requirements of the GCOD both because it will be a substantial renovation of the portion of the YMCA structure that will be incorporated into the project and because it will cover over 50 square feet of new space. Therefore, it must meet the requirements to not cause reductions in groundwater levels on the site or adjoining lots and to provide the specified amount of capability to capture and recharge stormwater. I am pleased that the proponent committed to do so during the scoping session on April 30.
According to the PNF, foundation design is at a relatively early stage. The proponent should be required to give more details of the design and how it will assure that it cannot cause reductions in groundwater levels in the Draft Project Impact Report. The DPIR should also make clear whether the proponent plans to install foundation underdrains and, if so, the provisions included to assure that these drains cannot cause any reduction in groundwater levels in the upper aquifer that is critical to maintaining the integrity of wooden pilings. I am pleased, in that context, to note the commitment to waterproofing the lower basement walls and basement slab.
In order to make sure that the project is meeting its groundwater performance commitments, it will be important to monitor groundwater levels around the site before, during, and after construction. While the Trust monitors several wells in the vicinity of the site, it will be necessary to install additional wells to adequately understand what is happening. The well monitoring frequency should be specified, and monitoring reports should be provided soon after they are taken to both the BRA and the Trust. The new wells should be installed in public sidewalks if possible, should be built to BGwT standards, and should be incorporated into the monitoring network after completion of the project.
I appreciate the cooperation that the proponent and its team have shown in agreeing to meet groundwater standards. I look forward to working with them and the Authority to assure that this project can serve only to help with our efforts to increase groundwater levels in the impacted areas.
Very truly yours,
Elliott Laffer
Executive Director
Cc: Kathleen Pederson, BRA
Maura Zlody, BED
