WorldWide Drilling Resource

Tales from the Field by Jeremy C. Wire Geoconsultants, Inc. WorldWide Drilling Resource ® welcomes Jeremy as a contributing writer. He is president and principal hydrogeologist at Geoconsultants, Inc. and has worked extensively in the hydrogeology field since 1961. He has been honored by several geological societies and organizations, including the California Groundwater Association establishment of the Jeremy C. Wire Award to honor its technical members of merit. The Saga of “The Well from Hell” Anyone who has been involved in water well drilling projects for any length of time, especially drilling contractors, occasionally get involved in a well drilling operation which seems, despite best-laid plans, everything that can go wrong does, sometimes from the start. We call these projects the “wells from hell”. These jobs may be rare, but they do happen and particularly try the skill and patience of the drill crew and everyone else involved. Worse, they often “blow” the budget. The outcome may be un- certain at best; sometimes good, sometimes bad. In this particular case it was . . . well, you’ll need to read on for “the rest of the story” as the saying goes. The locationwas inNorthernCalifornia, where a rural public utility district needed a large-diameter well drilled. The geo- logic setting involved volcanic rocks, noted in the region for difficult drilling conditions at best, with such potential geologic hazards as large open fracture zones, lava tubes, rubble zones, and “block and ash” intervals consisting of hard blocks of rock (sometimes as large as small cars) surrounded by soft ash. We had some idea of subsurface condi- tions from a nearby test hole drilled and logged ten years previously, but for various reasons, a well was never completed at the time. The project started by drilling a new small-diameter test hole to a depth of 300 feet. The first indication of prob- lems to come was caving of the bore- hole so an electrical log could not be run below a depth of 200 feet despite re- peated efforts to clean the hole. The log- ger had another job to do and finally had to leave. It always seems these kinds of problems occur when a location is re- mote from the logging service com- pany’s home base! In any event, the production wel l was designed using what information was available from both the new and previous test hole. A reverse circulation rig was then mobilized to the site, but by time late fall arrived with subfreezing temperatures. The drill crew discovered the hard way that diesel fuel in equipment from a warmer climate will “gel” without a proper additive, a problem which caused some delay. In addition, drilling the 24-inch-diameter bore through the hard, but fractured, volcanic rock took several passes, taking more time than expected, compared to the relative ease of drilling the test hole. Small hole diameter drilling does not necessarily correlate to drilling a large-diameter hole Wire cont’d on page 34. April 19-21, 2017 Spearfish, SD Spearfish Holiday Inn and Convention Center Phone: (800) 999-3541 • (605) 642-4683 For room booking use group code: BIW www.holiday-inn.com/spearfishsd James McNulty: (605) 786-4959 • bitwconference@gmail.com Doug Hoy: (605) 940-1055 • dough@sayreassociates.com For more information, or to register online, go to: bitwconference.org What you can expect from this conference: Regulatory session • Crazy Horse Mountain Tour • Paul Muehl ScholarshipClay Shoot • BobMartinScholarshipGolf Scramble • primer social hour • technical sessions • booster social hour • banquet • live scholarship auction • exhibitor booths with the latest in blasting technology and products • lunch • door prizes • and much more! Blaster recertification credit hours available for Wyoming and many other states! See you there! 26 FEBRUARY 2017 WorldWide Drilling Resource ®