Passport Potash appears to be planning on developing an underground mine with capacity of about 2 million tons of potash per year, according to an interview in the White Mountain Independent newspaper. There has been speculation that Passport might 'flip' their property to a large company for development or to use solution mining rather than underground mining.
American West Potash has publicly announced plans for a 2+ million ton underground mine that they project could be in production in 2014. [Right, thickness map of potash in the Holbrook basin. AZGS Open File Report 08-07]
Passport development director Ken Bond said they are in it for the long term and projects costs of about $1 billion to put a 2 million ton mine in production, although he indicated Passport is perhaps a year behind American West in their estimated timetable.