Conducting the Environmental Impact Analysis and Assessment - Environmental Impact Analysis: Process and Methods - page 215

and superior dispersion and dilution provided by discharge locations in
deeper water farther from shore. In the final analysis, there was a consensus
decision among:

r The Massachusetts Water Resource Authority, the owner, and opera-
tor of the wastewater system
r The Massachusetts Department of Environmental Protection, the
state regulatory and permit issuing authority
r The U.S. EPA, the federal regulatory and permit issuing authority
r The CAC and TAC
r The litigants in the lawsuit that forced the court-supervised cleanup
of Boston Harbor

All of these stakeholders agreed that degraded benthic habitat of 1.2 km 2
or greater and changed habitat greater than 12.2 km 2 were unacceptable
(Figure 5.17). Similarly, the consensus decision was that any area of degraded
water column with respect to nutrient enrichment and a changed area greater
than 4 km 2 were an unacceptable level of impact and did not meet the pur-
pose and need (Figure 5.18). Thus secondary treatment with a discharge at Site
5 resulted in impacts below the significance criteria and was selected as the
proposed action.

Site 5

Site 4

Site 2

km 2
Area changed
Area degraded

Site 2
32.7
2.2

Site 4
18.9
1.2

Site 5
12.2
<0.1

Changed Area
Degraded Area

FIGURE 5.17
Areas of Boston Harbor exceeding impact significance criteria for benthic habitat.