Completion and testing of Madison Limestone test well 3, NW1/4SE1/4 sec. 35, T.2N., R.27E., Yellowstone County, Montana

Selected intervals in the lower and upper parts of the Mission Canyon Limestone of Mississippian age, and the Amsden Formation and Tensleep Sandstone of Pennsylvanian age, containing water with dissolved-solids concentrations of 3,000 milligrams per liter or less, were perforated through 7-inch casing that was cemented to the wells of the borehole. Total flow from all perforated intervals after development of each interval by swabbing and flowing was 125 gallons per minute. Total flow increased to 2,900 gallons per minute after acidizing and fracturing each unit through perforations. Radioactive tracer surveys indicate about 65 percent of the flow was from perforations in the upper part of the Mission Canyon Limestone. Based on analysis of data from a step-drawdown test, the values of transmissivity and coefficient of storage considered as most reasonable are 38,000 gallons per day per foot and 0.00002 respectively. Maximum temperature of water, measured at land surface, was 56.6 degrees Celsius. (USGS)