DE RIDDER LA 15 MIN QUAD MAP USGSWATER QUALITY STATION MAP NO 51 OFFICE OF WATER DATACOORDINATION USGSMSHA METAL-NONMETAL MINE FILE REFERENCE 2/25/80LA DEPT OF TRANSPORTATION AND DEVELOPMENT QUALIFIEDPRODUCTS LIST 2 7/1/81FILE DATA LA DEPT OF TRANSPORTATION AND DEVELOPMENTNASA-AMES RESEARCH CENTER INFRA RED PHOTOS 79-164 NORTH LA1979MSHA INSPECTION INFO 9/1/81