 |
2007 Ground Water Summit |
Tuesday, May 1, 2007 : 1:50 p.m.
Frequently Committed Offenses against the Rules of Water Well Construction
There exist quite a number of possibilities to commit mistakes in the course of planning and realization of groundwater wells. Some of them strike a mortal blow to a well project, making the construction unsuitable to collect groundwater in adequate yield or quality. This kind of “well killing” is mostly due to a grave lack of expertise by either the project owner and/or his consultant, or occasionally the contractor. Sometimes project owners do not realize the importance of a professional project evaluation based on sufficient and correctly interpreted preliminary investigations and, every so often, even an experienced consultant fails in his objective. Nevertheless, the greater part of mistakes have no real killing potential, but they can accelerate well ageing, well colmation or groundwater contamination, or generally said, can gravely harm the preservation of a well’s value. This kind of offenses against the rules of well construction can be illustrated plausibly by a number of case examples, which originate from a long experience of consulting and contracting for water well construction worldwide:
· Disadvantageous choice of well location or well system
· Wrong choice of screen specifications
· Gravel pack inadequate to natural granulometry of formation and/or to the slot size of screens
· Incompetent prediction of drilling or shaft sinking conditions
· Errors in the evaluation of groundwater hydraulic parameters
· Inadequate risk analysis, for instance regarding artesianism, development potential, long term operating
· Well development not completed
· Insufficient consideration of the requirements of groundwater protection
· Disadvantageous choice of well location or well system
· Wrong choice of screen specifications
· Gravel pack inadequate to natural granulometry of formation and/or to the slot size of screens
· Incompetent prediction of drilling or shaft sinking conditions
· Errors in the evaluation of groundwater hydraulic parameters
· Inadequate risk analysis, for instance regarding artesianism, development potential, long term operating
· Well development not completed
· Insufficient consideration of the requirements of groundwater protection