DOE/EIS-0332; McNary-John Day Transmission Line Project Draft ...

BPA McNary-John Day Transmission Project
Draft EIS
February 2002
Air Quality
20 vehicles (pickups, vans), three bucket trucks, one conductor reel machine, three large
excavators, one line tensioner, and one helicopter.
The amount of pollutants emitted from construction vehicles would be relatively small
and similar to current conditions with the operation of agricultural equipment in the
project site and vicinity. Such short-term emissions from construction sites are exempt
from air quality permitting requirements.
Construction activities that could create dust include access road improvements and
construction, and work area clearing and preparation. Most access roads would be on the
native surface (dirt roads or sparse vegetation), but air quality impacts are expected to be
localized, temporary, and controlled as practicable.
Impacts During Operation and Maintenance
Air quality impacts during operation and maintenance of the project would be negligible.
Operation and maintenance vehicles would mainly use access roads with native surfaces,
causing dust particles to be stirred up. Quantities of potential emissions would be very
small, temporary, and localized.
Environmental Consequences—Short-Line Routing Alternatives
Air quality impacts for the various short-line routing alternatives would not differ from
those identified above.
Mitigation
The following mitigation measures would help to control dust and reduce emissions.
� Water exposed soil surfaces if necessary to control blowing dust.
� Cover construction materials if they are a source of blowing dust.
� Limit vehicle speeds along dirt roads to 25 miles per hour.
� Shut down idling construction equipment, if feasible.
Unavoidable Impacts Remaining after Mitigation
Unavoidable impacts from the project include low levels of combustion pollutants and
dust from vehicles during project construction and maintenance.
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