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Notes from the Groundwater Guy by Thomas E. Ballard, P.G., C.H.G. Southeast Hydrogeology, PLLC The Four Most Common Causes of Well Problems As anyone in the well business can attest, there are many problems which can crop up with water supply wells, but they generally fall within four categories. 1) Well Construction Issues - Many ongoing issues related to well performance can generally be traced back to the well design and related construction. Key well design issues we often see include: j Screen size is too large or too small, allowing sanding to occur or restricting flow of water into the well; j Filter pack is mismatched to the screen size, resulting in ongoing sanding issues; j A smaller well diameter than indicated by aquifer conditions, resulting in high entrance velocities and turbulent flow to the pump; j Inadequate well seal, resulting in surface water infiltration and potential contamination of water in the well. 2) Well Development Issues - A well which is not developed properly can continue to underperform throughout its entire life. Proper well development is a process which not only removes drilling fluids from the borehole, it also creates an effi- cient flow path of water from the formation into the well. Inadequate development results in an inefficient well, resulting in pumps which have to work harder and increases operating costs. 3) Aging - Well aging can be affected by well construction and water chemistry factors. Older mild steel well construction does not have the life span a stainless steel well construction does. Similarly, more corrosive groundwater conditions can also shorten the life span of a well by corroding the well screen and casing. While all wells will age at different rates, they all have a limited life span which will result in well performance degradation over time and eventual failure. While well aging is not preventable, its effects can be mitigated to some degree by regular well rehabilitation and maintenance. 4) Neglect - Just like you would not drive your car for 200,000 miles without ever changing the oil, neither should you operate a well for 50 years without ever performing maintenance or doing a rehabilitation on the well. Where conditions exist which can cause incrustations or bacterial plugging of wells, timely rehabilitation of wells is critical to maximizing the life cycle of the well. Recognizing and understanding these factors can be an opportunity to assist our clients beyond just the well installation phase and build a business relationship which lasts throughout the life of the well. Tom Tom Ballard may be contacted via e-mail to michele@worldwidedrillingresource.com --- *+ )#)('-()$* !(& )(%#'" +)""+ ,'.*,+ -'"/ 0 . 1 1 1 1 16 APRIL 2018 WorldWide Drilling Resource ®