Vertical Loop Installation Options
Our drillers are licensed and trained professionals meeting the health and safety requirements as mandated by OSHA 29 CFR 1910.120 and the State regulatory agencies governing our work. We are IGSHPA Accredited installers and hold valid licenses to drill in Kentucky, Illinois, Indiana, Iowa, Missouri, and Ohio.
Methods used to construct vertical boreholes:
Air Rotary Drilling
This method is used to construct boreholes in rock formations. High pressure, high volume compressed air is forced down the drill string to flush cuttings out of the borehole. A Down Hole Hammer (DHH) is attached to the bottom of the drill string and used to break rock in a process similar to a jack hammer breaking concrete. No fluids are reclaimed or recirculated when using this method.
Mud Rotary Drilling
This is the most common method used in our service area. Mud Rotary Drilling is the most efficient method of drilling unconsolidated or soft overburden formations. Fluid, usually clean water with engineered bentonite additives is circulated from a mud tub through a suction hose by a mud pump and forced down the drill string through portals in the drill bit to flush cuttings out of the borehole while the bit is fed down the hole. The fluid and cuttings are then run through a series of separation chambers so that the solids can be removed and the fluid recirculated.
"NO MESS" Mud Rotary Drilling
This method is ideal for mud drilling conditions in finished lawns or tight commercial locations. We bring a drilling rig, a water truck, a Mud Technologies solids separation device, and a compliment of pumps and hoses. Standard mud rotary methods are used for borehole construction but the drilling fluids are pumped to the Mud Tech where the solids are deposited into a pile or a waiting loader depending on conditions. When drilling and grouting is complete, the fluid is pumped into a water tank. This method reduces 90% of the mess of standard best practices. Using our "No Mess" approach along with compacting the excavated header connection soils is the quickest path to a restored landscape.
Combination Air and Mud Rotary Drilling
This method is used when unstable formations are found on top of hard rock formations. The process is relatively simple but more time consuming than either separate method. The mud rotary method is used to drill down to the bedrock zone. When it is necessary to stabilize the formation steel casing is inserted into the hole. The Air rotary method is then used to complete drilling to the desired depth. Once the loop has been inserted and the borehole has been properly grouted the steel casing can be removed from the hole.
The most important part of any vertical loop field installation is proper grouting. The only approved method of grouting a vertical borehole is called tremie grouting. It is sometimes also refered to as pressure grouting. The way it works is fairly simple, once the loop has been installed into the borehole, another hose must be run down to the bottom of the borehole. It is paramount that the tremie hose reach the BOTTOM of the borehole before the grouting process begins. By pumping from the bottom of the hole up, you can be assured that the water in the hole is completely displaced with high solids, low permiability bentonite grout. The grout provides a median of heat transfer between the loop pipe and the earth and most importantly protects any water bearing zones from possible introduction of surface contaminants.