Miner County is a rural agricultural area of 572 sq mi in east-central South Dakota. All streams in the county are intermittent and usually are recharged only from spring snowmelt and precipitation. Most ponds and sloughs may go dry in summer and during drought conditions, while larger lakes and ponds will contain water year round. Three major confined glacial aquifers underlie Miner County. The Floyd aquifer, buried beneath 25-150 ft of glacial drift, ranges from 10-100 ft in thickness. Water levels in the Floyd range from flowing to 56 ft below land surface. Properly constructed wells in the aquifer may produce as much as 1,200 gal/min. The Floyd aquifer offers the greatest potential for irrigation or other large yield development. Predominant chemical constituents in water from the Floyd aquifer are sodium, calcium and sulfate; however, there is a wide variation in the chemical composition of the water. For the most part it is suitable for irrigation. The Howard aquifer, is buried beneath 80-350 ft of glacial drift and ranges from 4-170 ft in thickness. Water levels in the Howard aquifer range from 16-200 ft below land surface. The Ramona aquifer underlies about 70 sq mi and is buried beneath 25-170 ft of glacial drift and ranges from 4-32 ft in thickness. Water levels in the Ramona range from 10-105 ft below land surface. Four bedrock aquifers underlie Miner County. The uppermost aquifer is the Niobrara Formation, buried by 60-600 ft of Pierre Shale and/or glacial drift with a thickness ranging from 10-120 ft. Water levels in the aquifer range from 6 ft above land surface to 200 ft below land surface. The Codell Sandstone Member of the Carlile Shale which underlies the Niobrara Formation is at depths ranging from 120-720 ft below land surface. It ranges from 10-120 ft in thickness. Water levels in the Codell aquifer range from flowing at land surface to 235 ft below land surface. Water from the aquifer generally is not suitable for irrigation. The Dakota Formation is buried by 400-1,000 ft of bedrock and glacial drift and is separated from the Codell aquifer by overlying carbonate rock and shale. The Dakota aquifer ranges from 10-400 ft in thickness. Water levels in the aquifer range from 25 ft above land surface to 260 ft below land surface. Water from the aquifer generally is not suitable for irrigation. (Lantz-PTT)