WorldWide Drilling Resource

present [fractured granite block and cob- ble] a small rig with ‘mud motor’ capabilities proved ideal for completing the bore.” Even with the use of the 36x50 rig, the unstable ground presented a final challenge for the project. The last step in- volved pul l ing the 6-inch stain- less steel well material through the bore. While pulling back, un- stable fi l l be- neath the edge of the founda- tion crushed a portion of the end of the stainless steel well screen. After discussions with the owner and consultant, it was decided to use spe- cialized tooling to sever the ‘stuck’ well materials near the point of collapse leav- ing 230 feet in place. Four-inch stainless well materials (riser and screen) were pulled through the inside of the 6-inch materi- als and through the collapsed section, completing the installation of the drain. The system is ready to be brought online, and hopefully the hydroelectric facility will soon be generating power again. 20 AUGUST 2013 WorldWide Drilling Resource ® Using HDD to Prevent Water Contamination by Dan Ombalski, P.G. and Jason Yablonski, Directed Technologies Drilling, Inc. Directed Technologies Drilling’s (DTD’s) new dual rod directional drilling rig was recently put to the test by in- stalling a 300-foot horizontal drain in Connecticut. The drain was installed under a former industrialmill built onanatural stone (granite) foundation along a local river. The former mill was repurposed as a small hydroelectric plant by directing water flowing from the adjacent mill race into two new turbines beneath the build- ing, and then discharging into the river. Regulating agencies halted power gen- eration at the plant due to a fuel oil plume (located underneath the building) which was being drawn into the turbines and discharging to the river. The plan was to install a drain using horizontal direc- tional drilling (HDD) technology, to be used as a conduit to divert the oil away from the tail race so the facility could be repermitted to generate power. DTDbegan the project with a standard horizontal drilling rig, but subsurfacemate- rials prevented advancement of the con- ventional jetting assembly. It turned out the ground between the stone foundation walls was backfilled with debris of all variety: gravel, concrete, and rebar. Stepping up the technology to meet this challenge, they mobilized their new dual rod direc- tional drill rig to complete the bore. Utilizing dual rod technology, Vermeer designed a mechanical, dual-rod system on a 36x50 platform to allow the drill bit to spin independently of the drill stem. This system differs from a conventional mud motor which uses high mud flow to hydraulically turn the drill bit independent- ly of the drill stem. Conditions at the site called for technology beyond convention- al due to the local geology (cobbles, boul- ders), a granite block retaining wall to unknown depth, three granite block foot- ers, and various site constraints (small drill rig footprint, maximum bend radius of entry and exit curves, etc.). The 300-foot drain was designed to be double-ended with the exit approxi- mately 25 feet above the entry location. The dual rod system proved to be ideal to complete the pilot bore and reaming pass, overcoming the nonideal conditions. James Ditto, DTD’s drilling superinten- dent, discussed the need for the drill switch. “Drilling within close proximity to the river, minimal setup space, and the geology plenty of time to hydrate and yield. If you slow down during mixing, you will get more product in suspension, which can lower your usage cost. The fourth and final factor is the product itself. There is always the pos- sibility you got some bad product. How- ever, it has been my experience over these many years that if you are using Baroid IDP QUIK-GEL ® , or an equiva- lent product such as SUPER GEL-X ® from CETCO ® , or EXTRA HIGH YIELD™ from Wyo-Ben , etc., you are getting a good product; and any problems you are having are more than likely the result of one of the other factors dis- cussed above. The statements and comments in this article are my own and are based on information and references believed to be true and factual. If you have a question or comment on this article, or on bentonite drilling muds, polymers, grouts, or additives, please forward them to me in care of WWDR . Ray admin@ worldwidedrillingresource.com McLarty cont’d from page 17. Centerline Manufacturing Co. 903-725-6978 903-725-3647 fax ~ Mud pumps for the 21st century ~ www.centerlinemanufacturing.com ~ Centerline mud pumps are getting the job done from Canada to Australia, China to Peru ~ ©WorldWide Drilling Resource, Inc. 2006 Centerline Manufacturing is proud to be your complete stocking source for American Manufacturing mud pump parts!! U.S. Patent #6,769,884 and others pending Monopump models rated: 180 gpm Duplex models rated: 300 gpm Triplex models rated: 450 gpm 500 or 800 psi models available aluminum or iron. ~ The Centerline 7 1/2” x 10” hydraulic drive mono mud pump ~ ~ compact ~ fits on top or under deck ~ pumps the rated flow of a 5” x 6” @ over twice the rated pressure ~ weighs 650 lbs, 1615 lbs less!