environmental assessment for the hog lake road improvement project

Ramona Hog Lake Road Improvement Project August 2011
Coarse particles (larger than 2.5 but smaller than 10 micrometers, or PM10) come
from a variety of sources, including windblown dust and grinding operations. Fine
particles (less than 2.5 micrometers, or PM2.5) often come from fuel combustion,
power plants and diesel buses and trucks. Fine particles can also be formed in the
atmosphere through chemical reactions. The SCAB is designated as a nonattainment
area for both state and federal PM10.
Sulfur Dioxide: SO2 is a colorless, pungent gas formed primarily by the combustion
of sulfur-containing fossil fuels. SO2 irritates the respiratory tract, injures lung tissue
when combined with fine particulate matter and reduces visibility and the level of
sunlight. The SCAB is designated as an attainment area for both federal and state
sulfur dioxide standards.
Lead: Pb is a gray-white metal that is soft, malleable, and resistant to corrosion.
Sources of lead resulting in concentrations in the air include industrial sources
and weathering of soils, followed by fugitive dust emissions. The SCAB is
designated as an attainment area for both federal and state lead standards.
Direct and Indirect Effects
For purposes of meeting Federal requirements, impact significance is related to
Federal conformity with the U.S. EPA-approved State Implementation Plan (SIP) and
with the national ambient air quality standards (NAAQS). Air quality impacts would
be considered significant if they are expected to cause or contribute to an air quality
violation in a non-attainment or maintenance area. However, if total direct and
indirect project emissions fall below designated Applicability threshold levels
established under the Conformity Rule, no adverse change in attainment status is
expected. For purposes of meeting State requirements, Air Quality Management
District (AQMD) thresholds of significance for project emissions serve the same
purpose as the Federal applicability thresholds.
No Action:
The No Action alternative includes the continuing operation of Hog Lake Road
without the implementation of any road improvements. This would cause no new
adverse impacts to air quality, however there would continue to be impacts from
vehicle emissions (ozone, carbon monoxide, nitrogen dioxide, and sulfur dioxide),
and the fugitive dust produced from driving on the unpaved surface would add to
particulate pollution (PM2.5 and PM10).
Proposed Action:
The implementation of the Proposed Action is not expected to have any long-term
detrimental effect on air quality. Long term, the paving of the road is expected to
actually reduce particulate matter pollution, as dust generation by vehicles would be
much less on a paved surface than on an unpaved one. Additionally, paving the road
will result in less friction, which will improve vehicle gas mileage and reduce exhaust
emissions, due to improved engine efficiency. Traffic volumes are not forecast to
increase significantly with implementation of the proposed project and traffic
Frank Springer & Associates, Inc. Page 35 of 79 Environmental Assessment