Final Environmental Impact Report - Whittier Bridge/I-95 ...

Whittier Bridge/I-95 Improvement Project FEIR
Chapter 2.0: Response to Comments on the Environmental Assessment/Draft Environmental Impact Report
MassDOT has also provided each conservation commission with an independent peer review of the
Notice of Intent applications.
DEP-18: Tables 6 to 9 list a number of wetlands where no stormwater treatment appears to be proposed for
redevelopment drainage. In application of the macro-approach, which provide stormwater standards may be met on
sub-watershed basis versus at each separate discharge outlet, disproportionate impacts to any one wetland must still
be avoided. For example, drop inlet structures may be able to be converted to deep sump catch basins to provide at
least some level of TSS treatment to avoid disproportionate impacts to any one wetland.
Response: The comment is noted. MassDOT has provided supplemental information to the
conservation commissions to demonstrate compliance with the standard as described in
section 1.4.2.
DEP-19: Additionally, Tables 6 to 9 should be reviewed to ensure MassDOT is properly credited with treatment to
wetlands it appear to be proposing but may not have taken credit for. MassDOT will need to document to each
conservation commission that the redevelopment drainage within their town boundaries meet the TSS standard
through exercise of macro-approach to maximum extent practicable and improve existing condition.
Response: The comment is noted. MassDOT has provided sufficient information to the conservation
commissions to demonstrate compliance with the standard as discussed in Comment DEP-10 and
DEP-17.
DEP-20: MassDOT has indicated to MassDEP that there are no discharges in the Zone II in Newburyport, limited
recharge in the Zone II of Salisbury, no discharge or treatment in the Newburyport Zone A, and no direct discharge,
other than from scuppers, into the Merrimack River. This information should be confirmed in the FEIR.
Response: As noted in the comment, there are no stormwater discharges located in the Zone II in
Newburyport, limited recharge in the Zone II in Salisbury, no discharge or treatment in the
Newburyport Zone A and no direct discharge other than scuppers into the Merrimack River.
DEP-21: Design of Wet Basin 9A in conjunction with Infiltration 9B needs to be reviewed further to ensure wet basin
treatment is not short circuited.
Response: The comment is noted. MassDOT has provided this information to the Salisbury
Conservation Commission.
DEP-21A: A long term pollution prevention plan (LTPP) needs to be provided to each conservation commission as
part of meeting stormwater standard 4 (310 CMR 10.05(6)(k)(4)(a) and 314 CMR 9.06(6)(a)(4)(a)). The LTPP needs
to identify source control activities to be implemented. The LTPP needs to be specific to the Whittier Bridge project. A
generic state-wide plan is not sufficient to serve as the LTPP.
Response: MassDOT has prepared a project-specific LTPP and submitted it to the conservation
commissions as part of the wetlands permitting process. The LTPP is attached as Appendix A. In
general, LTPP measures and related maintenance activities will be conducted consistent with the
MassDOT NPDES Stormwater MS4 Permit, and the measures outlined in MassDOT‘s Stormwater
Management Plan (SWMP). LTTP measures identified in the document include the following: litter
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