Experimental evaluation of reservoir bottom remediation material

Open trenches developed through a compacted clay liner on the bottom of a reservoir. An experimental investigation has been conducted to evaluate the feasibility of using silt-sized, nonplastic silica, dolomite or hematite regrind concentrate placed underwater as a slurry to fill the void space. The investigation consisted of conducting index property and permeability tests on soils representing a range of foundation conditions in the reservoir and on the three proposed filler materials; consolidation tests on the proposed filler materials; and filter tests on composite specimens of foundation soils and filler materials. The results indicate that all proposed filler materials placed as a slurry to fill the trenches will not pipe through the underlying soil under the action of the imposed hydraulic gradient, and will consolidate sufficiently to produce a low enough coefficient of permeability so that significant head loss should be established across the filler material.