WorldWide Drilling Resource®

Notes from the Groundwater Guy by Thomas E. Ballard, P.G., C.H.G. Southeast Hydrogeology, PLLC It’s Just a Well I don’t normally discuss ongoing projects in this column, but I wanted to share a current well project that might be of interest to everyone. The well in question is approximately 700-feet deep and located in an area with known natural gas shows. The well was planned as a replacement production well for a medium-size water district. A local engineering firm was contracted to oversee the well design, drilling, and construction. This firm has an excellent reputation, but does not have a lot of water well experience. I mean, it’s just a well, right? How hard can it be? The new well was drilled and completed with minimal testing, other than a pumping test. Everything checked out and it looked like they had a good well except they were getting a lot of methane intrusion into the well. So much, in fact, the well is presently unusable. The engineering firm spent months trying to get the methane under control with little success. The old production well was shallower and had no methane issues, so the engineering firm finally proposed to just seal the bottom 350-400 feet with concrete to try to address the issue. It seems a bit desperate to just concrete up the lower half of a expensive new well when you have no idea where the methane is even coming from. This is where we got involved. Our approach is to conduct vertical profiling of the well to identify the geologic zones where the methane is intruding into the well, categorize the high flow zones, and develop a plan to modify the well to seal off the methane zones while minimizing any impacts to the production capacity of the well. So what could they have done differently from the outset? For one, understanding the geology of the area and potential contaminants you are likely to encounter is extremely important, as you can test for problems as you drill and even profile the test boring to design a well that will seal off problematic zones. It’s a lot less expensive to conduct the appropriate assessment during the test boring phase than to try to modify the well after it is already built. The other thing which could have been done differently is to use the right diagnostic tools for the job. Just proposing to seal the entire bottom 350-400 feet of the well without any knowledge of where your problems are located is questionable, at best. Remember, it is more than “just a well.” Tom Tom Ballard may be contacted via e-mail to 38 SEPTEMBER 2020 WorldWide Drilling Resource ® WTR Blasting Guide App Now Available Adapted from a Release by BME South Africa BME South Africa launched a new, free Blasting Guide application for Android mobile devices, which enables users to quickly calculate and check blast designs. It is currently available for download from the Google Play Store, replacing traditional paper booklets carried and referenced by in-field users. The app is a series of guiding formulas, a powerful means of verifying blast design outputs, allowing a blaster or engineer to plan a blast from start to finish. It includes a blast design calculator, quick calculators, and prediction calculators, along with surface blast design rules of thumb, environmental guidelines, a table of common rock properties, and a BME contact directory per country. The app also runs both metric and imperial unit measurements, making it useful across the globe. The calculator utilizes user inputs, including burden, spacing, stemming height, subdrill, hole diameter, bench height, and explosive type to determine explosive loads, powder factors, and other outputs. “The new app is an integral part of BME’s pioneering approach to harnessing the power of digital technology in the blasting sector,” said Christiaan Liebenberg, software product manager at BME. “This platform gives our Blasting Guide a mobility and ease of use that makes a blasting engineer’s job easier and more productive.” EXB