Draft Environmental Impact Statement for Roca Honda Mine

Chapter 3. Affected Environment and Environmental Consequences
Constituent
Mt. Taylor Johnny M RHR Mine
11/15/1979 11/07/1979 Water Quality
NMQCC Irrigation Use
Groundwater Standards
Al 1.12 5
B 0.2 0.75
Co 0.02 0.05
Mo 0.13 0.612 0.62 1
Ni 0.02 0.2
EPA NPDES
TSS 30 daily max, 20 mo. Ave.
COD 200 daily max, 100 mo. Ave.
Zn 0.07 1.0 daily max, 0.5 mo. Ave.
Ra 226 (dissolved) 10 pCi/l daily max, 3 pCi/l mo. Ave
Ra 226 (total)
30 pCi/l daily max, 10 pCi/l mo.
Ave.
U 7 4 daily max, 2 mo. Ave.
pH 8.5 6 to 9 su
Notes: Mg/l unless otherwise noted. Highlight = value above corresponding NMWQCC standard
Effects on Flooding or Flood Plains
For the proposed action the potential for flooding is anticipated to be moderated by the
construction of ponds and storm water controls. The facilities are not in the flood plain and would
have no effect on flood plain function. From the hydrologic analysis performed by RHR, culverts
and detention ponds were sized adequately to hold the expected amount of runoff from each of
the developed areas for a 100-year storm event. Further, based on historical measurements of
streamflow, streams in the area are capable of conveying higher streamflow without routine
flooding events.
Reclamation Phase Effects
The RHR reclamation plan revision 1 describes the storm water erosion controls that would be
part of reclamation. These controls include:
• Disturbed areas would be stabilized through grading areas to conform to the geomorphic
character of the region and surrounding area, including shaping, berming, and grading to
final contour.
• Slope lengths and gradients would be minimized.
• Both runoff and runon would be diverted from reclaimed areas to prevent erosion of
reclaimed areas.
• Vegetation would be reestablished.
• Existing natural drainage arroyos would be preserved and/or improved.
158 DEIS for Roca Honda Mine, Cibola National Forest