Oxbow NWR Final CCP - U.S. Fish and Wildlife Service

River: USFWS photo
Chapter 3: Refuge and Resource Descriptions
hour ozone standard for many years. However, with the adoption of
numerous control programs, progress has been made. The number and
severity of the 1-hour ozone exceedances has declined significantly in
recent years. As of 2002, the entire state was in violation of the 1-hour and
8-hour standards based on ozone readings for the 1999-2002 period.
USEPA is expected to designate the attainment status of the State for the
new 8-hour ozone standard in 2004. Massachusetts is expected to be
nonattainment for the 8-hour standard.
In 2002, there were 122 exceedances of the 8-hour standard occurring on 30
days, and 22 exceedances of the 1-hour standard occurring on 5 days on a
state-wide basis. A total of six 8-hour exceedances were recorded in 2002 in
Stow. The trends for ozone readings in the State have been generally
decreasing toward better quality since 1988.
Massachusetts has made significant progress in attaining the CO standard
by implementing air pollution control programs. The last violation of the
CO National Ambient Air Quality Standards (NAAQS) occurred in Boston
in 1986. The Boston Metropolitan area was redesignated to attainment of
the CO federal air quality standard by the USEPA in 1996. Lowell,
Springfield, Waltham, and Worcester were redesignated to attainment of
the CO standard by the USEPA in 2002.
In recent years there has been concern regarding the aerial deposition of
mercury from atmospheric sources outside the northeast region (see for
example Sweet and Prestbo 1999). Researchers have speculated that this
may be the source of mercury levels found in some species and age-classes
of fish in New England above the 1 ppm standard established by the U.S.
Food and Drug Administration (USFDA).
The annual average concentration of lead in the air decreased substantially
since 1985 from more than 300 ug/m 3 to less than 0.05 ug/m 3 (the annual
average NAAQS for lead is 1.5 ug/m 3 ). Massachusetts is well below the
standard. This result is attributed to the use of unleaded gasoline in motor
vehicles, which are the primary source of airborne lead emissions (MADEP
2000). While air quality concentrations of lead have dramatically decreased,
there may still be concern regarding residual lead levels in soils along
heavily traveled roadways deposited prior to the change to unleaded
gasoline usage.
Water Quality and Quantity
The waters of the Nashua River have been designated as Class B,
warm water fisheries by the Commonwealth of Massachusetts.
Class B waters are defined as being suitable for “protection and
propagation of fish, other aquatic life, for wildlife, and for primary
and secondary contact recreation” (MADEP 1998a). Although
vastly improved in water quality character, the Nashua River has
Comprehensive Conservation Plan
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