Methods of restoring the delivery of drainage wells

Abstract

1. During the operation of a drainage system, the reduction in well productivity is governed by chemical-silting processes, the rate of which is determined, in many respects, by the design of the permeable portion of the well. 2. Use of the pneumatic-impulse treatment of wells with an interrepair period of not more than 6 months is possible in wells that have been in service for not longer than 3–4 years. 3. In wells that have been in service for 5–10 years, treatment by the detonation of a blasting fuse ensures the restoration of productivity up to 65–45% of the initial yield. A rational interrepair period is 8 months. 4. Solution of silting formation in a well that has been in service for not more than 6–7 years is ensured by-concentrated hydrochloric acid and solutions of powdered reagents. The recommended interrepair period as a function of the design of the water-receiving portion of the well is 18–24 months. 5. Use of combined methods of treatment is expedient in wells that have been in service for more than 7–8 years where interrepair periods of 24–30 months have been observed. 6. Experience acquired with the massive restoration of the productivity of drainage wells in a flood-control system in an area within the region of the Kuibyshev Reservoir can be used in developing measures to stabilize the effect of vertical drainage of terrace dams and flood-protection systems under similar hydrogeologic conditions.