1. Distribution and mass of nitrate in the unconfined aquifer beneath the intensively cultivated area north of the Rio Grande, San Luis Valley, Colorado, 1997 through 2001 Author/Creator: Stogner, Robert W. Publication/Creation: Reston, Va. : U.S. Dept. of the Interior, U.S. Geological Survey, 2005 Format: Book Access & Availability: Loading
2. Quality of ground water in agricultural areas of the San Luis Valley, South-Central Colorado Author/Creator: Edelmann, Patrick, author Publication/Creation: Lakewood, Colorado : U.S. Geological Survey, 1984 Format: Book Access & Availability: Loading