Apr 07, 2010

Well Managed

A private military school in Southeast Wisconsin derived its water supply from two wells. One was more than 80 years old and the Layne pump had not been serviced in more than 20 years. As a long-term customer, the school turned to Layne Christensen Co. for service.
After removing the pump, Layne staff found that the well showed significant signs of deterioration. Well casing was collapsing and the well was not salvageable. Only one well was left to serve the school’s population of more than 200 students, plus residence staff.
Through its internal team of hydrologists, Layne researched well logs and discovered a sand and gravel aquifer that had not been tapped. The shallow supply, only 175 ft deep, was found to be capable of producing more than 600 gal per minute (gpm) while the school’s existing wells had been nearly 1,000 ft deep and supported, at best, 300 gpm.
Layne drilled this shallow well, tapping a reliable, shallow water source that saved well drilling costs, reduced pumping costs and avoided potential radium treatment had a deep well been constructed.
Layne designed a complete pump station, designed and supplied iron filtration equipment, and supplied and installed a VFD and PLC-driven submersible pump feeding the varying demands from 100 to 400 gpm for both domestic and irrigation use. The irrigation demand operates from one local and one remotely positioned booster skid.
The treatment system uses LayneOx filter media, a highly efficient granular catalytic media with a naturally high manganese dioxide content. While only iron is present at this location, the efficiency of the media provides the ability to remove iron, manganese, hydrogen sulfide and arsenic, all in one backwashable process. The media’s high loading rate of 7 to 10 gpm per sq ft reduced the overall size of the treament plant. This smaller footprint resulted in lower construction costs for the client.
A custom-programmed design scheme, also created by Layne , controls the various demands. Domestic demand takes precedence while irrigation demand is limited to 200 gpm. The resulting multi-functioning system is user friendly and uniquely designed to meet multiple demands and varying flow rates. The supply system provides iron filtration for potable use, with backwashing during non-peak hours. Iron removal is accomplished through a chlorine feed system that oxidizes the iron combined with skid-mounted LayneOx pressure filters that then remove the oxidized iron. The same system can provide untreated water for irrigation.
The military school now enjoys a new well, improved overall capacity and filtered water for drinking and other domestic applications from a safely managed aquifer.