Geonex horizontal hammer drilling completed a 175 ft crossing in mixed ground with precision—no settlement, fast execution, and strong interest from across the U.S.
Horizontal hammer drilling saves the day
One casing was for a water main, while the other was for a gravitational sanitary sewer. The crossing length was 175 ft, and the soil was fractured bedrock in the beginning and turned into mixed soil with cobbles and occasional boulders. The drilling path also penetrated some perched groundwater pockets. The job was first specified for Auger boring, but penetration into the rock face turned out to be insufficient. After trying with auger boring, the project turned to Horizontal hammer drilling. The job was carried out in four days, including mobilization to the jobsite. Both holes were drilled successfully, and grades were well inside tolerances. The highway experienced no settlement or heave and the actual conduct pipes will be installed inside the casings with centralizers. Overall, a very successful project. Contractors interested in the method came to see the job all the way from California.
The project was carried out by EBI Drilling from Duluth, Minnesota. EBI Drilling has been mainly doing HDD drilling, and they have many years of experience in trenchless contracting. In 2017 EBI Drilling invested in Geonex drilling systems. EBI Drilling has two rigs HZR220 & HZR400, and they have PP90 Power Pack to drive both rigs. With these two rigs they can offer drilling service in diameter range of 5½” – 20″. EBI Drilling will grow their Geonex machinery fleet all the way to 48″ drilling diameter. EBI offers their services all over the United States.
Exceptionally hard rock – no problem
This project was a spot-on case for the Geonex horizontal hammer drilling. This method is especially strong where ground conditions vary from hard rock conditions to compacted mixed soil conditions. This method can drill exceptionally hard rock, and it is common in Scandinavia to drill over 50,000 PSI rock. It uses the same drill head for every soil type, which makes Geonex horizontal drilling method very adaptive and cost-efficient in varying soil conditions. Supporting soil types also enable reasonably good accuracy, even though no active steering is used. This method is also used with no issues in river crossings where significant groundwater is present.