Pilot Testing
Regardless of the remedial material selected, the efficient distribution of the material in the subsurface is often the limiting factor that determines success or failure. Therefore, on-site pilot tests can be used to determine the best subsurface tooling and injection protocol. During a pilot test, injectates can be injected at high flow/low flow, high pressure/low presssure, auger/packer or geoprobe rods
, etc. The information gleaned from a pilot test injection event can be critical to the injection design at large sites or where there are variable and/or problematic stratigraphic conditions. Typically, a pilot test is designed to determine the following parameters:
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The radius of influence from each injection point
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The volume of injectate that can be injected into each injection point with surfacing
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The maximum down-hole pressure that can be used without surfacing
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The character fo the subsurface in terms of vertical/lateral permeability
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The existence and character of access issues
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The impact of utilities in establishing an injection grid