WorldWide Drilling Resource

Using Sonic Drilling Rigs for Geothermal Projects Adapted from Information by Sonic Drill Corporation Sonic drilling is known for its speed when drilling through sand, silt, and gravel. However, on one particular project, the drilling speed surprised even the company who manufactures the sonic drill rig. A Sonic Drill Corporation rig was used by Hemmera Energy, a division of Hemmera Environmental Services Consultants of Vancouver, British Columbia (B.C.), Canada, to drill a geothermal test hole. Remarkably, the rig bored past 300 feet and complet- ed the hole in just over two hours. The project was part of a law library extension for the University of B.C. In the initial phase of the project, the company was asked to conduct a fea- sibility study to see if it was practical to install a geothermal field in the proposed extension. “Our role is to do the test holes to see if a larger scale project is feasible,” said Christiaan Iacoe, an environmental scientist and consultant at Hemmera Energy. “If you’re going to drill 200 holes or more, it’s good to know the conditions.” The initial hole was drilled using a conventional mud rotary rig, but when the rig got past the 320-foot mark, it stopped dead in its tracks. The sonic drill was brought in as a rescue rig, and it quickly and easily chewed through the same challenging conditions which jammed the conventional rig. When it comes to test holes, Iacoe says any fai led attempts are just as useful as ones that are successful. “If it shows it’s not realistic to drill at that site, that’s really impor- tant. Our job is to produce a feasibility report, so what we do is drill the test hole and install a geothermal test loop . . . We also pinpoint challenges at each site for full-scale construc- tion. We have a lot of experience working with . . . Sonic, and they can drill through things other drills can’t,” added Iacoe. “Their drill holes are fully encased so there is not as much sloughing, and they can grout a borehole and retract the cas- ing, compared to a mud rotary, which just leaves an open hole.” Sonic Dri l l Corporation rigs use an award-winning, patented drill head to transmit vibrations and power through a drill string. This produces energy which liquefies overburden and bedrock while pushing the material up and away from the drill pipe. This enables a sonic drill to achieve penetration rates 3-5 times greater than conventional drilling systems. 20 NOVEMBER 2018 WorldWide Drilling Resource ® In remote locations where the size and weight of the equipment you need can add significant cost and inconvenience to a project, the little dipper2 water level meter from Heron Instruments, Inc. is small enough to carry in a backpack for easy transport. Its polyethylene-jacketed, high-tensile steel tape is available in three lengths with either metric or engineering scale markings. The 5/8-inch probe is full pressure rated, plus a 3/8-inch probe is available for narrow openings. A padded case is included. Heron Instruments, Inc. is a Valued WWDR Advertiser GEO