HomeMy WebLinkAboutAgenda 05P_Exhibit 021 Environmental Impact Letter 07 13 20 finalGilman & Briggs Environmental, Inc.
1 Conti Circle, Suite 5
Barre, Vermont 05641 Tel: (802) 479-7480; FAX: (802) 476-7018
team@gbevt.com
11 June 2020 Andrew Gill
O’Brien Brothers 1855 Williston Road South Burlington, VT 05403 Dear Andrew,
This is to summarize our findings at the O’Brien Home Farm site during fieldwork on 8 October 2019. Arthur Gilman and I visited the site to investigate environmental resources, to include wetlands, wildlife habitat, and rare, threatened and endangered species. Our work encompassed the area from near the existing barn off Old Farm Road down slope to the east, eventually along
the southern property line to the SE corner of the parcel, then northerly, delineating wetlands along the eastern margin of the property. Wetland areas along the northern side of the property were then delineated, including low spots in fields near Kimball Avenue and a long riparian wetland on a tributary stream to Potash Brook that is culverted under the street.
Wetlands associated with Potash Brook and those along tributary streams near Kimball Avenue are considered Class II wetlands protected under provisions in the Vermont Wetland Rules. The borders of these wetlands were flagged so that development plans can avoid them and any impact to them and their associated buffer zones. Provided development does not disturb the wetlands or their associated buffers, their functions and values will remain intact. Smaller
isolated wetlands in wet meadows near Kimball Avenue that are not contiguous to Class II wetlands and do not meet the presumptions in Section 4.6 of the Rules would be Class III. These may, however, fall under U.S. Army Corps of Engineers jurisdiction. These Class III wetlands were also flagged so that development plans can account for them as appropriate.
Although all undeveloped land at the project site may be used by wildlife at some level, areas that rise to significance (i.e., they demonstrate diversity of community and structure that can support a variety of wildlife species) are concentrated in forested areas along Potash Brook at the eastern margin, particularly low mixed woods at the toe-of-slope. Much of these areas are included in the buffers associated with wetlands and the Brook and therefore will remain
unimpacted by the proposed development. Open fields, especially those that have been managed as hayfields for decades, offer limited cover for wildlife, usually limited to mice, other small rodents and some grassland songbirds Although fields may be used as feeding habitat by such species as turkeys and deer, and also by
rodent predators, such areas do not constitute core habitat.
Forest cover is primarily found in two areas of the property. The wooded area on the ridge between open fields and the stream is dominated by mature hemlock, with little or no understory community; as such, it has low diversity for wildlife habitat. Other scrub/wooded or shrub areas
on the project site (such as the small knoll adjacent to Kimball Avenue) provide habitat for species common to suburban habitats near human activity (particularly near Old Farm Road and the heavily traveled Kimball Avenue), these species would include turkeys, rabbits, skunks, raccoons and other common animals. There was no evidence of large mammals, however transient deer may visit the property. Given that these species are adapted to living in suburban
areas, and are relatively common in South Burlington, it can be expected that they will continue to use available habitats even with development on other sections of the property. The woodland along the eastern side of the property is part of a cluster of woodlots along Potash Brook, hemmed in by commercial development along Kimball Avenue to the east, along
Williston Road to the north, and by Interstate 89 to the south. It can be expected that wildlife utilizing this area consists primarily of resident species rather than species requiring extensive non-fragmented habitats. These fragmented wooded patches are not included as a “Habitat Block” in the ANR Natural Resource Atlas, even though nearby but disconnected woodlots to the north, east and west are included, and even these are ranked as low priority (at level 2 out of
10). The presence of non-resident transient species is related to their ability to travel freely due to the need for a fairly large territory. This freedom of movement is already limited in this area and should not be encouraged in proximity to heavily traveled highways and other major road networks where human/wildlife interactions result in frequent wildlife mortality. While animals naturally shy away from such areas, the volume of vehicular traffic already present in this area
poses a threat to transient species. No rare, threatened or endangered species are indicated on the ANR Natural Resource Atlas for this area. None were identified during our fieldwork, nor are there specialized habitats on the
property that are likely to support such species.
This field evaluation found no evidence of any rare or irreplaceable wildlife communities or species on the Project site, nor was there evidence of significant environmental resources other than wetlands and stream buffers which have been flagged and will be avoided. Prudent
development on this property will not have undue adverse impacts on any significant habitats,
and will not involve removal of any high priority forest block mapped by the Agency of Natural Resources or those included in the recent Arrowwood Environmental mapping commissioned by the City of South Burlington.. Sincerely,
Errol C. Briggs