Abstract

The updated demonstrated reserve base estimate of coal for the San Juan Basin, New Mexico, is 11.24 billion short tons (st). This compares with 4.429 billion st in the Energy Information Administration's demonstrated reserve base of coal as of January 1, 1993 for all of New Mexico and 2.806 billion st for the San Juan Basin. The new estimate includes revised resource calculations in the San Juan Basin, in San Juan, McKinley, Sandoval, Rio Arriba, Bernalillo and Cibola counties, but does not include the Raton Basin and smaller fields in New Mexico. These estimated "remaining" coal resources however, include significant adjustments for depletion due to past mining (through 1994), and adjustments for accessibility and recoverability.

The updated estimates also incorporate analyses of available sulfur, heat, and ash content data appropriate for characterizing the State's remaining coal resources. Coal quality data were examined together with coal resource mapping. Samples from exploration drill holes and coal coring, and samples from locations in or near mines within traditional coal fields were used in the allocation of coal resources. These resources were subdivided based on sulfur and Btu content. The new allocations place 28 percent of the demonstrated reserve base of the San Juan Basin, New Mexico, in the 0.41-0.6 sulfur category. In the previous allocation by the Energy Information Administration 34 percent for all of New Mexico was in this sulfur category.

As part of the current study, factors affecting coal resource availability and recent data on mining recovery rates were also examined. Based on the new estimated demonstrated reserve base, the accessible reserve base for the San Juan Basin is 10.28 billion st, and recoverable reserves are 7.65 billion st for New Mexico.