Hydrofracturing

Remediation Injection

Packer Services

Borehole Video Camera

The Application of Injection Rate and Pressure

The high flow rate capabilities of the injection equipment have proven very effective in providing superior distribution of treatment chemicals in sandy materials. The high flow rate effectively fluidizes the sand allowing the treatment chemical to be delivered. This is especially valuable with granular injectates.

Soil samples taken from 20-25 foot depth interval in a very well sorted, fine grained, dune sand showing even distribution of Remediation Products Inc. activated carbon based treatment product known as BOS 100®. The most distant soil sample was five feet from the injection point.

Surface test of injection tip at 175 GPM and an exit velocity of 7300 ft/min.

In conjunction with the high flow rate injection pump, custom injection tips have been developed to provide a range of injection exit velocities to meet a variety of subsurface conditions. Depending on the lithology, exit velocities in excess of 20,000 ft/min can be applied to insure formation penetration. The higher exit velocities minimize the development of preferential flow paths and virtually eliminate surfacing problems.

The high pressure capability of the injection equipment has proven very effective in treating sites where the contaminant has progressed into bedrock materials. The high pressure is helpful in parting bedding planes in consolidated and semi-consolidated formations. The materials often behave as if being hydrofractured by showing a high breakdown pressure at a relatively low injection rate. Once the breakdown occurs, the injection rate is increased to distribute the treatment chemicals and maximize the radius of influence.

Distribution of breakdown pressures from 344 injections made between 18 and 23 feet below ground surface in a claystone bedrock formation. Breakdown was initiated at 33 GPM and a BOS 200® slurry was delivered at 72 GPM.

The high pressure capabilities of the pump can be utilized with direct push equipment or with inflatable packers in boreholes. Where the competency of the bedrock prohibits the use of direct push equipment, injection holes can be drilled with auger, sonic, or rotary-air rigs. Based on the objectives of the injection program and the drilling equipment being used, packers (single or straddle) are available for a variety of hole diameters.

Inflation test of straddle-packer string to be used for the placement of Regenesis ORC®. The ORC® slurry was injected into 4" PVC screened wells in a Pleistocene sand and gravel between 155 and 180 feet at injection rates in excess of 100 gpm. Because of the high permeability of the formation, only 140 psi was required for the injection.

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