Leached zone : phosphate recovery /

"U.S. AEC Contract AT(49-1)-545."

Leached zone : dissolution of values using heat treated feeds /

"U.S. AEC Contract AT(49-1)-545."

Federal and Indian lands coal, phosphate, potash, sodium, and other mineral production, royalty income, and related statistics.

Fiscal year coverage, 1971-1975; calendar year coverage, 1976-1980.