"Providing Innovative Water and Wastewater Solutions"

St. Johns County Florida School District

USWSC currently operates and maintains the treatment facility and in early 2007 began an analysis and feasibility assessment to determine alternate means of RO concentrate disposal. The system consists of (2) groundwater production wells drawing water from the shallow aquifer. Raw water is treated with antiscalant and then pressurized to approximately 110 psi. and pumped through a low pressure Reverse Osmosis treatment skids. RO permeate is then treated with carbon dioxide gas to lower pH prior to degasification for more effective hydrogen sulfide removal. After degasification, water is treated with sodium hypochlorite for disinfection and sent to a ground storage tank. Water is then pressurized using high service pumps and a hydropneumatic system. Currently RO reject water is injected with carbon dioxide and sent to a degasification unit prior to surface water discharge into a stream approximately 2 miles from the facility.

USWSC provided start-up and commissioned the operations of the facility providing technical support, troubleshooting membrane performance problems, assisting with contractor punch list development, site inspections, interfacing with membrane manufacturers, performance testing and all other requirements necessary for start-up and owners approvals.

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