Water Well Journal
Issue link: http://read.dmtmag.com/i/451364
Summary Even with the age of the existing well, the various types of well testing performed indicated a productive and usable well with a reasonably straight and open borehole to a minimum depth of 180 feet below ground surface (Fig- ure 2). The observed flow rate of 215 gpm with 50 feet of drawdown (a 91- foot pumping water level) equated to a specific capacity of 4.30 gpm per foot of drawdown. The extrapolated maximum usable capacity of the well, therefore, was estimated to fall between 350-400 gpm at a maximum pumping level of 180 feet. Testing of the physical characteristics of the cased and uncased sections of the well indicated an acceptable amount of alignment and plumbness to permit in- stallation and safe operation of up to a single 10-inch nominal diameter (9.50- inch OD actual) vertical turbine pump bowl assembly or a parallel (offset pump locations) two-pump, 6-inch- diameter submersible pump/motor assembly to a depth of up to 180 feet below ground surface. The water quality was found to be generally acceptable for the intended uses with very low or nondetectable concentrations of inorganic and physical water contaminants. There was no indi- cation water produced from the well would contain a large or prohibitive volume or physical size of sand, grit, or .other deleterious particulate matter, which would then require filtration or treatment before heat pump use, irriga- tion, or aquifer reinjection. The tests indicated the existing pro- duction well would be adequate for all intended geothermal uses, but the com- petition for this use, given the limited production plus the availability of a mu- nicipal water supply at the site, would preclude its additional use as a potable water supply well. In addition, the favorable test results on the well and aquifer also demon- strated direct reinjection of the return water to the aquifer would not only be feasible but preferred as this type of sys- tem would not place an undue burden on the aquifer or other neighboring wells in use and would most likely gain favor from the regulatory agencies WWJ February 2015 39 Twitter @WaterWellJournl Figure 2. Pringle Creek community existing production well. the DR can drill without fluids the DR can drill without fluids el, glacial till, and boulder v a gra e bee v t DR drills ha emos or F w er in lo er in lo t a t w t w ec ec t o de o de y t y t s the abilit s, the abilit es the li thod minimiz he DR me s. T r edly in some of t t epea en r v o n pro ed ed. v o tions is impr tions is impro orma orma w f w f -flo flo w tion and aqu cula s cir elihood of los k erb v ed o t onsolida t unc oughes he t tion. Because tamina on s-c os er cro uif tions, including sand orma den f bur e d, o drill. Canada ( 1.9190 .66 1.800 or call fo , visit e o learn mor To y t a er w t t be ti oduc o the pro tributions t on c s Dual ' t emos or , F 9 7 e 19 Sinc s orldwi (W 5.5800 3.29 1.40 .S.A.) a/U DR ca/ t. emos or or t a y of opera ofitabilit y and pr ivit ed on the ere e deliv v otary drills ha R y , wing numbe Eng DE ) de o or a gro . F orldwide w . e ormanc er perf t t omise of be e pr p s simply no try e indus c esour or the r ed solutions f ineer ESIGN. BUILD. PERFORM. e' ther s, or t ac tra on er of c e significan o mak tinue t on y c he T o . y . t ENGINEERING continues on page 40