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Title: Hydrogeology of the Point Lookout Sandstone in the San Juan structural basin, New Mexico, Colorado, Arizona, and Utah

Book ·
OSTI ID:6940177

This report is one in a series resulting from the US Geological Survey's Regional Aquifer-System Analysis (RASA) study of the San Juan structural basin that began in October 1984. Summarized is information on the geology, occurrence and quality of water in the Point Lookout Sandstone, one of the primary water-bearing units in the regional aquifer system. Water in the Point Lookout Sandstone occurs under both water table and artesian conditions. Potential recharge to the aquifer is from infiltration of precipitation and streamflow and from vertical leakage of water through confining beds. The average hydraulic conductivity calculated from oil and gas wells in the deeper parts of the basin is 0.0058 ft/d. The reported or measured discharge from 17 water wells completed in the Point Lookout Sandstone ranges from 1 to 75 gallons per minute and the median is 10 gpm/ft of drawdown and the median is 0.25 gpm/ft of drawdown. From a total of 37 samples for pH, 22 exceeded the standard. Out of a total of 43 samples for sulfate, 16 samples exceeded the secondary drinking water standard. Only 1 sample for chloride out of 49 samples exceeded the standard. From 44 samples for fluoride, 9 samples exceeded the secondary drinking water standard of 4 mg/L. Twenty-nine samples from a total of 42 samples for dissolved solids concentration exceeded the secondary drinking water standard. No samples for nitrate exceeded the primary drinking water standard of 10mg/L.

OSTI ID:
6940177
Resource Relation:
Related Information: USGS Hydrologic Investigation Atlas HA-720-G
Country of Publication:
United States
Language:
English