WCC is expected to assume responsibility of operation of the San Juan Mine from 1 January, 2016, and until then both the companies will ensure a smooth ownership transition.
Following the deal, WCC will be able to supply the coal to the San Juan Generating Station (SJGS) beyond 2017.
According to BHP Billiton New Mexico Coal president Pat Risner WCC would ensure the continuation jobs and a sustained revenue stream for local communities.
Risner added: "We will continue to work closely with our employees and the communities we serve to ensure a smooth ownership transition to WCC."
The sale process is also conditional on the Public Service Company of New Mexico (PNM), obtaining necessary approvals from the New Mexico Public Regulatory Commission (NMPRC).
