W2 Engineering Offers Geotech Drilling Services with 3100GT

Started in 2012 as a geotechnical and materials testing firm, W2 Engineering, Oklahoma City, subcontracted a lot of its drilling. According to Arvel Williams, president, they found they needed better control of their schedules and decided to move forward with drilling services both internally and externally. With more than 30 years of experience in the industry, the W2 management team began doing its due diligence reviewing all of the various manufacturers.

“What we found is that almost all of the manufacturers have not improved on their equipment over the past few decades,” Williams said. “Except for carriers, auto hammers, and moving to more modern engines, most of the mechanical drill rigs were the same design that was used 40 years ago. Almost all of them were above CDL, which, in this day and age, causes administrative issues. Where the rig was below CDL, it was usually underpowered for HSA drilling.”

However, the Geoprobe® 3100GT was set up to drill for geotechnical work and had the features and power they were seeking. From a management perspective, W2 especially appreciates the rig doesn’t require a class A/B Commercial Driver’s License (CDL) and the fuel mileage, resulting in significant overhead cost reduction.

“Most rigs get 8-10 mpg or less. We have seen an over-the-road mileage of up to 15 mpg,” Williams said. “This is a reduction in fuel cost of 1/3. Combine that with maintenance on only one engine and we anticipate the operating overhead will drop significantly using this piece of equipment.”

From an operations perspective, the driller values the hands-free controls along with the quietness of the 3100GT. The driller appreciated being able to actually carry on a conversation next to the rig when its drilling. According to Williams, at 40 feet, wet rotary with pump and rotation the sound level was 70-73 dB at the drillers station.

W2 recently completed a 21-hole alignment through some undeveloped areas of central Oklahoma City. The 3100GT performed SSA, HSA, and wet rotary drilling with both SPTs and Texas cones. Formations varied from alluvial terrace with fine saturated sands to hard sandstone with SPT blow counts of 50 for ½ inch.

“We drilled to 70 feet with no issues,” Williams said. “The rig performed as promised. The secondary pump running auxiliary equipment was a big help when wet rotary drilling."