WSP03001 - Laserfiche WebLink

Home Browse Search

MWSI Project Phase II Conjunctive Use Summary Report - DRAFT August 22, 1995 all the water injected into an aquifer. The rules also hold that artificially recharged water can be stored indefinitely in the aquifer. The Denver Basin Artificial Recharge Extraction Rules are not concerned with water quality issues, Injection water quality and its compatibility with aquifer water is the concern of the Environmental Protection Agency (EPA), A Class V UIC permit is required from the EPA to inject water into a Denver Basin aquifer. The Slate's rules require compliance with all other State and Federal regulations, Recharge Economics The capital, operational and maintenance costs related to Denver Basin aquifer injection are dependent on amount of water to be injected, Higher injection rates require larger diameter wells and pipes and higher horsepower pumping equipment. In both the Willows and Centennial projects, retrofit work was performed on existing wells to allow for injection. The amount of work required for the Willows project was more extensive than the work required for the Centennial project since Willowi connected to the Denver Water system. Retrofit for the Willows project included: a 12-inch pipeline from Denver's Conduit I I I, a meter vault, a backflow prevention vault, injection vault piping, modification to the pitless adapter, pulling and resetting of the downhole equipment, a flow meter and engineering, Willows reports that the total cost of the injection retrofit at Well A-6A was $370,000. Centennial reports that the retrofit cost for work only related to Well A-6 was approximately $50,000, In their third quarterly report, February to June, 1993, JHA presents cost information on the Willows project on a dollars-per-I,OOO-gallon basis, The following costs are presented. - Treated water $] .23/1 000 gallons - System retrofit $0,12/1 000 gallons - Well pumping $0.45/l000 gallons - Operation and Maintenance $0,1911000 gallons - Water quality analysis $0.10/1000 gallons - Total $2.09/1 000 gallons The cost of treated water to inject is the largest cost in the Willows injection project cost estimate, The $1.23/1 000 gallons rate is Denver's wholesale wintertime rate. The retrofit cost of $0.12/1 000 gallons was based on a 20-year equipment life, a maximum injection rate of 600 gpm and a six-month injection season. The cost of $2,09/1 000 gallons is higher than Willow's amortized cost from its Denver Basin wells which is reported by JCH to be $1,00/1 000 gallons, 17