November 2009

In This Issue:

• Origin of Dissolved Arsenic in Bangladesh Ground Water
• Newly Drilled Ice Cores from the Andes
• Ground Water Project Wins DOE Recognition
• New Drilling Fluid Research Funded
• Tiny Bubbles Clean Oil from Water
• Lessons That May Help Address Ground Water Crisis
• Water Is Found on the Lunar Surface
  
• Court Halts Unlicensed Drilling by Public Entity
• SMU Geothermal Lab Awarded $5.25 Million Grant
• Active Volcanoes in East Africa
  

Oscillation-drilling: Sending Up
Good Vibrations on Utah Bridges

Drilled shafts are nothing new in the bridge construction industry; along with pile foundations, drilled shafts are one of the two most common foundations used to secure large structures like bridges. In Utah, however, the not-so-common oscillation method of drilling holes for enormous underground pillars of concrete provided a solution in a construction area that called for careful mitigation and quick execution.

The Utah Department of Transportation (UDOT) Region 2 EXPRESSLink project is building three bridges on I-15 between Salt Lake County and Davis County in Utah. Oscillation-drilled shafts are being used at the bent foundations of each bridge. Located at Beck Street, U.S Highway 89 and 1000 North in Salt Lake County, the bridges are in areas replete with construction conflicts including silty soil, a high water table and proximity to businesses, residents, pressurized utility lines and railroad tracks. The oscillation-drilling method addressed each of these issues, and allowed UDOT to keep a tight schedule.

The drilling operation on the EXPRESSLink project was conducted by Malcolm Drilling Co., a Seattle-based firm with 10 years of experience in oscillation drilling. Malcolm's method uses an oscillator to push casing into the ground, then soil is excavated from within the casing.

The UDOT Region 2 job at Beck Street required a 3-meter (9.8-ft.) casing oscillator to drill a 2.8-meter (9.18-ft.) diameter shaft. Malcolm used reusable casing segments bolted together to reach depths of 115 feet to 120 feet.

The job required two cranes. A Kobelco 2500CK 250-ton crane was used to lift and place the casings. A Liebherr dual-cycle crane was used to suspend a hammer-grab clamming shell with a jaw that opens and closes. As the oscillator displaced soil, the clamming shell removed and loaded the soil from the casing directly onto trucks for clean removal from the construction site.

Read more about this project in the National Driller December 2009 issue.

Origin of Dissolved Arsenic in Bangladesh Ground Water Identified

Researchers at MIT believe they have pinpointed a pathway by which arsenic may be contaminating the drinking water in Bangladesh. Their research suggests that human alteration to the landscape and other practices are responsible for the current pattern of arsenic concentration underground.

(Photo credit: Charles Harvey, MIT.)

Astec Underground introduces the new Astec EarthPro Geothermal 4550 (truck-mounted) and 4550X (track-mounted) drill rigs designed to meet the specialized demands of geothermal system installations.

Engineered for high-production drilling applications, the EarthPro Geothermal offers a dual rack and pinion design; there are no chains, cables or hydraulic cylinders to replace. The three-speed drive motors are said to allow quick trip times with strong 45,000 pounds of pull-up and 22,000 pounds of pull-down. The automated pipe-loader system permits a single operator to drill and trip out up to 600 feet of pipe without winch assistance; its pipe basket can hold up to 30 pieces of 20-foot pipe in 3.5-, 4- or 4.5-inch diameters. The EarthPro Geothermal carries a 1,050-cfm Sullair compressor with a maximum pressure of 350 psi to drill deeper and faster, and to operate larger hammers. The drill is powered by a Caterpillar C15 ACERT turbocharged diesel Tier 3 Stage IIIA engine that develops 580 HP at 2,100 rpm and 1,953 ft.-lbs. of torque at 1,400 rpm.

Additional features include central ergonomic controls, a hydraulic key/vise table design, and tethered two-speed ground drive system. Optional equipment includes a water-injection pump, mud pump, tool lubricator and tank, and more.

For further information, visit www.astecunderground.com.

AEC Store Corner

Check out this BESTSELLER for the Drilling Industry!
Siting, Drilling, and Construction of Water Supply Wells - $187.00

You get professional and expert guidance in all aspects of water-well siting and drilling. Designed to be a practical reference, the book describes and illustrates all common drilling methods, geophysical logging and field testing. Well development is covered in detail, and well operation and maintenance are explained thoroughly.

Follow this link for a complete description or to purchase this item. To order by phone, call 248-244-1275.

To view all of our drilling resources, visit aecstore.com.