Draft Environmental Impact Statement for Roca Honda Mine

Environmental Consequences
Surface Water Resources
Alternative 1
Chapter 3. Affected Environment and Environmental Consequences
In the case of the no action alternative, there would be no impacts to surface water resources
beyond the naturally occurring effects of storm water, erosion, flooding, and drought that are the
existing conditions at the site.
Alternative 2
The proposed action has the potential to affect surface water resources, but these effects can be
mitigated by appropriate actions during construction, operation, and reclamation. The majority of
potential surface water effects are associated with storm water and its impacts on water quality,
sediment movement, and flooding. Other potential surface water effects are related to spring flow,
water rights, and treated water disposal.
The measures of whether surface water resources are affected by mining activities are:
• An increase or decrease in surface waterflow in the watershed compared to historical
conditions
• Introduction of surface water contaminants that would not otherwise be present in surface
water
Sections 4 and 5 of the mine operations plan (MOP) revision 1 addresses surface facilities and
performance standards for storm water controls. The surface facilities will have a disturbed area
of a total of approximately 183 acres within the permit area and 35 acres outside the permit area:
12 acres in Section 9, 71 acres in Section 10, and 100 acres in Section 16. The anticipated surface
facilities include: ore pads; retention (holding ponds), detention basins, diversions; wastewater
treatment facilities, water treatment facilities; warehouse and storage areas for equipment,
vehicles, chemicals and solutions; maintenance buildings; topdressing stockpiles, excavated
materials stockpiles; parking areas, truck wash station; mine shafts, vent shafts, and escape ways;
hoist buildings and head frames; roads; drill holes; dewatering wells; fences, power and water
lines; and surface runoff control features.
RHR proposes to dispose of treated water from the water treatment plant in a stock pond on
private ranchland whose owner intends to use this treated water to irrigate range or pasture land
for livestock. The estimated flow rate from the water treatment facility is expected to be 2,500 to
4,500 gpm. The treated water or effluent would be conveyed through a 20-inch diameter pipeline
approximately 8 miles in length to an offsite location northeast of the mine (figure 1-3 MOP Rev
1). This pipeline will be positioned next to the haul road and the utility corridor in Sections 16,
15, 10, and 11. The pipeline would be laid on the ground surface for ease of maintenance and
operation with an estimated total disturbed area of 13.3 acres. Almost the entire 8-mile length
would be across private land (10.8 acres of disturbed area), but the pipeline would also cross a
small portion of Cibola National Forest land (2.5 acres of disturbed area). The discharge would
occur on private property in the vicinity of Laguna Polvadera. At that location the water would
become available for reuse by others or may simply flow down the San Lucas Arroyo as a
permitted discharge.
DEIS for Roca Honda Mine, Cibola National Forest 147