Draft Environmental Impact Statement for Roca Honda Mine

Chapter 3. Affected Environment and Environmental Consequences
some expansion to confirm the predicted cone of depression. Monitoring of springs has occurred
in the past, both as to flow and quality, and is assumed to occur in the future, but specific plans
have not yet been provided by RHR.
Mitigation Measures
The large water level impacts cannot be avoided. For such impacts, NMOSE can require
mitigation in the form of requiring that replacement water be provided to users of groundwater,
and surface impacts be offset such that there is no net effect on streamflows. While reasonable
onsite mitigation can be required by the Forest Service, mitigation involving any such
replacement of water to non-Federal uses is subject to requriements of the regulating State
agency. NMED will specify measures required to prevent adverse water quality impacts from
occurring.
Air Quality
Affected Environment
Criteria Air Pollutants
The U.S. Environmental Protection Agency (EPA) Region 9 and the New Mexico Environment
Department (NMED) regulate air quality in New Mexico. The Clean Air Act (CAA) (42 United
States Code (U.S.C.) 7401-7671q), as amended, gives EPA the responsibility to establish the
primary and secondary National Ambient Air Quality Standards (NAAQS) (40 CFR Part 50) that
set acceptable concentration levels for seven criteria pollutants: particulate matter (PM10), fine
particles (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO), nitrous oxides (NOx), ozone (O3),
and lead (Pb). Short-term standards (1-, 8-, and 24-hour periods) have been established for
pollutants that contribute to acute health effects, while long-term standards (annual averages)
have been established for pollutants that contribute to chronic health effects. Each state has the
authority to adopt standards stricter than those established under the Federal program; however,
New Mexico accepts the Federal standards.
The NMED monitors levels of criteria pollutants at representative sites in each region throughout
New Mexico. For reference purposes, table 22 shows the maximum monitored concentrations of
criteria pollutants in the closest monitoring location in Bernalillo County, about 60 miles east of
the proposed site. McKinley County does not have monitoring sites due to its remote location,
and it is expected that the level of criteria pollutants would be lower than shown below.
Table 22. NAAQS and monitored levels of criteria pollutants
Pollutant and Averaging
Time
Primary
NAAQS a
Secondary
NAAQS a
Monitored
Data b
8-hour maximum c (ppm) 9 (None) 2.4
1-hour maximum c (ppm) 35 (None) 6.5
CO
Location
Bernalillo County
180 DEIS for Roca Honda Mine, Cibola National Forest