Various Well Rehabilitation Projects

Client: 
The City of Greater Sudbury
Contact: 
Brad Johns, P.Eng., Water Services Facilities Engineer City of Greater Sudbury Phone: 705-674-4455 ext. 3625
Brief: 
Rehabilitate and Service Wells and Lineshaft Pumps
Year: 
2007/2008
Project: 

Wells F & J
Lotowater performed well video inspections and testing of these wells and found that performance had declined.  The wells were rehabilitated using a series of acid treatments and surging by air displacement methods.  Lotowater inspected and serviced the 35 L/s, 50 hp lineshaft pump in Well F, and fitted Well J with a new 40 L/s, 60 hp lineshaft pump due to its poor condition.  The video inspection of Well F revealed significant corrosion of the well casing which could have compromised the structural and/or sanitary integrity of the well.  In order to provide a long term solution, Lotowater installed a stainless steel liner in this well to extend its functional life and eliminate concerns of casing failure.  

Inco-Garson Well
This well was rehabilitated with hydrochloric acid and mechanical surging using compressed air to remove screen plugging and restore the performance of the well.  The procedure consisted of installing an inflatable packer to isolate the screen from the casing, airlifting the well from the bottom until clear, injecting acid into the screened interval, surging the acid and letting it sit overnight, and airlifting the acid out the following day.  Due to the extensive amount of plugging of the well screen, a second acid treatment was applied.  A post rehabilitation video inspection showed that the mineral and biological growth had been almost entirely removed, and post testing of the well showed a dramatic improvement in well performance. The pump was disassembled, cleaned and inspected on site. The inspection revealed that it was in satisfactory condition with all wearing parts measuring within manufacturers tolerances.


Well M
The City had reported that the performance of this well had dropped substantially and Lotowater was called to performance an emergency rehabilitation and service on the well and pump.  The well was rehabilitated using a combination of EnerJet® treatment (an explosive/implosive stimulation system used to provide agitation to the gravel pack in order to remove restrictions in the perforations) and acid rehabilitation.  These treatments were accompanied by surging and airlifting to remove the loosened build-up.  The pump was taken back to Lotowater’s Paris, Ontario shop for inspection and all necessary repairs were made before re-installation.  The column pipe was thoroughly inspected in the field and any damaged end faces were repaired.