The Hydraulic Properties of the Ordovician Rocks at Pittsburg, Kansas

Abstract

This report describes aquifer tests made in March 1954 and February and March 1955 to determine the coefficients of transmissibility and storage of the Ordovician rocks at Pittsburg, Kansas. The report includes most of the data obtained during the tests and the analysis of the data. The general regional decline of water level in the Ordovician rocks in the Tri-State district is discussed.

The Ordovician rocks are the most important water-bearing beds in the Pittsburg area. They are composed of dolomite, shale, sandy dolomite, and fine-grained sandstone. The rocks do not crop out in the Pittsburg area but crop out many miles to the east in Missouri. The main water-bearing beds lie at a depth of 600 to 1,050 feet at Pittsburg.

The average values of the coefficients of transmissibility and storage computed from the aquifer tests were 250,000 gallons per day (gpd) per foot and 4.6 X 10^-4, respectively. The value of the coefficient of transmissibility is high compared to values obtained in other places where similar tests of the aquifer have been made.

To a considerable extent the decline of water level at Pittsburg probably has been due to pumping from mines in the overlying Mississippian rocks, as well as to pumping from the Ordovician rocks themselves.

A huge quantity of water is stored in the Ordovician rocks, which will continue to yield millions of gallons of water per day.