HDD Specs Developed For Ohio DOT

By Jeff Griffin, Senior Editor | March 2013, Vol. 68 No. 3

The team then compared and identified major areas of agreement and disagreement among these HDD specifications. The agreed-upon issues in the HDD specifications were used as the foundation for the proposed specifications. The issues of disagreement were analyzed and evaluated for inclusion in the specifications. These major areas of agreement/disagreement were then compared against the HDD Good Practices Guidelines manual to narrow down the list of points of disagreement for further research.

Document summary
The specification committee also reviewed HDD related publications by other DOTs and more in addition to the above cited specifications in developing the specifications. Below is a brief summary of what these collected specifications cover.

Drill Rig -- The standard describes the basic components necessary for a drill rig to ensure it has sufficient capabilities to successfully drill the pilot hole and pull back the product pipe effectively and safely. Its hydraulic system must be free of leaks. The machine must be anchored to the ground during drilling and pullback operations. It must have a system to detect and issue an alarm if the drill string approaches electric lines and to provide protection against electrocution.

Guidance System -- An electronic walkover tracking system or a magnetic guidance system (MGS) probe or proven gyroscopic probe and interface shall be used to provide a continuous and accurate determination of the location of the drill head during the drilling operation. The system must be remotely steerable and permit electronic monitoring of the drill bit’s depth and location. The system must be able to steer the pipe accurately to a window of two inches.

Personnel operating the guidance system must be trained and experienced in its use. When using a magnetic system, the operator must be aware of any magnetic anomalies and shall consider such influences.