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

Whittier Bridge/I-95 Improvement Project FEIR
Chapter 1.0: Changes Since the Draft Environmental Impact Report and Resolution of Additional Issues
Table 1-3:
Riverfront Area Mitigation – Newburyport
Existing
Impact Estimates
(sf)
Area of Riverfront on Site 356,000
Impacted
Areas (sf)
Areas
Subject to
RFA
Mitigation
(sf)
Existing Degraded 22,925 N/A
Previously Developed
(Engineered Sideslopes) 13,614 13,614
Undisturbed 1,060 N/A
Total 37,599 13,614
Temporary Impacted
Riverfront (Undisturbed) 4,770 N/A
Mitigation Rationale
Mitigation not required for redevelopment of
Existing Degraded areas.
Previously Developed areas (i.e. Engineered
Side Slopes / Previously Graded Areas) may
require mitigation under 310 CMR 10.58(5)(e)
Does not require mitigation under 310 CMR
10.58(4)(d)1, though undisturbed impacts
cannot cumulatively exceed 10% of RFA on the
lot.
Does not require mitigation under 310 CMR
10.58(4)(d)1, though undisturbed impacts
cannot cumulatively exceed 10% of RFA on the
lot. The 4,770 s.f. of temporary impacts will be
mitigated through "in kind" or in situ restoration.
Temporary Impacted
* Temporary Impacts will be mitigated through
Riverfront (Previously
"in kind" or in situ restoration, and are therefore
Developed) 15,590 * not included in the mitigation calculation below.
Overall Total 57,959 0 Includes permanent and temporary impacts
Mitigation Calculations
10% of total RFA 35,600
Existing Degraded 22,925
Difference between 10% of
site and Existing Degraded
= additional allowed
alteration without mitigation 12,675
Area Of Permanent
Previously Developed
Impacts 13,614
Required Mitigation under
310 CMR 10.58(e) 939
Proposed Restoration
Area for Permanent
Impacts 12,200
Proposed Restoration for
Temporary Impacts 20,360
Total Mitigation 32,560
Note: Refer to Figure 1-7 for locations of impacted and restored areas.
Proposed Impacts to permanent and temporary
Undisturbed RFA must not exceed 35,600 s.f.
under 310 CMR 10.58(4)(d)1. (project 29,770
s.f. below threshold).
The proposed work may alter up to 10% if the
degraded area is less than 10% of the riverfront
area on the site; 310 CMR 10.58(5)(e).
The redevelopment work may impact up to
12,675 s.f. without requiring Mitigation; 310
CMR 10.58(5)(e).
Difference between Impacts to Previously
Developed RA (13,614) and additional area to
achieve 10% degraded RA (12,675).
Mitigation provided at an approximate 5:1 ratio
for permanent impacts through restoration of
existing degraded areas.
Mitigation provided at 1:1 ratio for temporary
impacts (15,590 s.f + 4,770 s.f.)
Permanent Impact Mitigation + Temporary
Impact Mitigation.
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