WorldWide Drilling Resource

Notes from the Groundwater Guy by Thomas E. Ballard, P.G., C.H.G. Southeast Hydrogeology, PLLC Wait ~ Don’t Just File the Data Away! Oftentimes, well data such as laboratory analytical reports, specific capacity, and water levels are viewed as something to be glanced at when they are collected to see if there are any immediate issues. Then it is filed away, never to be looked at again. Instead of dumping it into the file cabinet, the best use of data collection is to format it to compare changes over time. Whether it is in a handwritten table or spreadsheet that calculates trend graphs, the collected data is most useful when put into a form to track changes in a well over time. This usually means tracking data trends using charts and graphs. Graphing data using a spreadsheet is relatively easy, and it presents a powerful visual which can be useful in determining the status of a well and in planning for optimal re- habilitation schedules and maintenance. While most of the useful data for a comparative analysis is likely being collected as part of a normal compliance and man- agement program, biological issues are an area which does not get monitored on a regular basis, other than for coliform tests. Yet many well problems are related to bacterial populations in the well, includ- ing obvious things like biofouling due to iron-related bacteria, but also mineral incrustations which can be produced or enhanced by biological activity in the well. At a minimum, well owners should add annual BART (biological activity reaction tests) for iron-related bacteria, sulfur-reducing bacteria, and slime for- mers, along wi th ATP (adenos ine triphosphate) tests for total bacterial count in the wel l . Trends in these parameters can indicate problems are developing, before they become critical (read this as expensive ) issues. This data analysis is most powerful when establishing baseline conditions - usually after a complete well rehabilitation or new well testing - to allow comparison of the changes over time. Oftentimes, a well rehab will “reset” the condition of the wel l and establ ish new basel ine conditions to compare to, moving for- ward. Plotting trends over time in chemi- cal, physical, and biological parameters to analyze changes in well conditions, which could act as an early warning sig- nal for developing well problems, pro- vides the maximum benefit from the data already collected, with very little extra effort. When it comes to prevent- ing unforeseen problems, i t is wel l worth the effort. Tom Tom Ballard may be contacted via e-mail to michele@ worldwidedrillingresource.com WTR 25 WorldWide Drilling Resource ® SEPTEMBER 2019