Draft Environmental Impact Statement for Roca Honda Mine

Chapter 2. Alternatives, Including the Proposed Action
interdisciplinary EIS team dropped this alternative from detailed consideration, and replaced it
with what is now the proposed action.
Single Production Shaft in Section 10
The interdisciplinary team considered, but dismissed from more detailed analysis, the option to
construct a single production shaft in Section 10. In this alternative, all of the ore in the permit
area would be accessed by excavating horizontally underground from this shaft to the ore
deposits. All of the facilities planned for Section 16 under the proposed action would be
constructed instead in Section 10. Construction of ventilation shafts and associated access in
Sections 9 and 16 would still be required. This alternative was dismissed from detailed analysis
for multiple reasons.
There is a concern about reducing the overall visibility of the mine facilities, especially from the
adjoining private land, the community of San Mateo, from Mt. Taylor, and those traveling
Highway 605. The Section 16 topography is defined by long ridges and valleys. The facilities in
this section were planned to be located as much as possible within the valleys, utilizing the ridges
to hide them from view. By contrast, the portion of Section 10 that would house facilities is an
open, gentle slope that is angled toward Mt. Taylor, the village of San Mateo, and the highway
and, thus, almost all mine facilities located on this slope would be readily visible from these
vantage points, as well as from adjacent private land. Placing the full facility on the topography of
Section 10 would increase the visual impact of the mine.
There is a concern with increasing traffic on Highway 605 past the village of San Mateo.
Locating one shaft and the mine facilities solely on Section 10 would funnel all traffic, including
all haul trucks, past the village of San Mateo. This impact would be greater for this alternative
versus locating the two shafts on Section 16 and 10, as proposed, or much greater than locating
one shaft on Section 16.
The mine plan of operations proposed to access the ore in Section 16 and then expand the mine
toward Section 10, where a second shaft was proposed to be constructed at a later date. Initial
access to the ore-bearing zone was proposed for Section 16 because the ore body is shallower in
Section 16 and the mine could be put into production sooner. The ore body in Section 10 is
deeper, and would require an additional year of underground drilling before it could be accessed.
In addition to the time factor, and also due to the depth of the ore body, the cost of a single shaft
located in Section 10 would be more expensive than a single shaft in Section 16. Both are
significant circumstances that would increase the costs of developing the mine before it could
begin to generate revenue.
Another impact associated with locating a one-shaft mine all on Section 10 (except for the
previously identified ventilation shafts) is that the surface footprint would be greater on Section
10 over a one-shaft alternative located all on Section 16. The total facilities footprint itself would
be similar in size to that associated with a one-shaft alternative in Section 16, but since the shaft
would be one-third deeper, one-third more waste rock would be generated in sinking the shaft.
This would necessitate a larger area for storing rock associated with shaft construction. The total
footprint (mine facilities plus all rock removed during shaft construction) for this alternative
would be larger than the footprint for having a one-shaft facility located in Section 16.
DEIS for Roca Honda Mine, Cibola National Forest 61