2010-07-27_REVISION - M1977223 (21)

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material differing substantially in texture or gradation from the surrounding material. The liner fill material shall be placed and compacted to a minimum of 95% of the maximum dry density as determined by a Standard Proctor Test (ASTM D 698). The liner fill shall be placed in a horizontal layer (lift) not to exceed six (6) inches in compacted thickness. The fill shall be added and compacted to achieve the minimum final compacted liner thickness. The liner thickness for the interior of the reservoir is as follows: Sidewall Thickness 18 inches Bottom Thickness 24 inches Each lift of the liner shall be compacted with a standard sheepsfoot roller, or other equivalent methods which must be approved by the Engineer. Roller feet or cleats should have sufficient length to penetrate the loose lift to - the underlying compacted lift in order to achieve good bonding at the lift interface. The sheepsfoot roller should not "walls out" as the lift becomes more compact, i.e., 1 to 2 inches of the lift being compacted should be left reasonably loose to allow the subsequent lift to effectively bond with the lift placed. The placement of lifts shall be accomplished such that there are no lenses or streaks of liner material; the liner should be a homogeneous unit. The used of smooth drum rollers is not acceptable. .Field Testing Requirements• As the liner material is installed, compaction testing shall be performed on each lift to document installation in accordance with the specification. The Geotechnician present on -site will notify the Contractor of any failing tests and the Contractor will make all necessary reparations to correct those areas failing field density testing. After repair of the failed areas, the Geotechnician will retest the corrected lift. Density tests shall be provided for every 600 cubic yards of material placed (or every 200 feet for 6 inch compacted material); verify with Engineer prior to construction. 5. Liner Water Content Water will need to be added to the clay material to achieve the proper moisture content for compaction. Water is available at the site for moisture control of the liner installation process. Water is typically applied using truck mounted tanks equipped with spray bars. The amount of water to be added should be sufficient to bring the moisture level of the soil mixture to somewhat wet of minimum. The higher water content (the closer to 90% saturation) will generally yield a lower permeability rate than the minimum water content. Immediately after application, the water should be thoroughly mixed into the liner material to eliminate surface porrding and enable the mixing equipment to operate without excessive loss of traction. The preferred method to add and mix moisture is to windrow the stockpiled liner material (outside the reservoir), apply water using spray trucks, and mix the material using a disc to create a homogeneous mixture. The moistened liner material may then be placed into the reservoir for compaction. The minimum water content of the liner fill material and foundation shall be determined by laboratory testing water content which is required to obtain the maximum dry unit density as specified by the Standard Proctor Test (ASTM D 698). The acceptable range of water content of the installed liner shall be -1% to +3% of the optimum moisture content. Field Testing Requirements: As the liner material is installed, moisture testing shall be performed on each lift to document installation in accordance with the specification. The Geoteclmician present will notify the Contractor of any failing tests and the Contractor will make all necessary reparations to correct those areas failing field density testing. Moisture tests shall be provided for every 600 cubic yards of material placed (or every 200 feet for 6 inch compacted material); verify with Engineer prior to construction. 310000 -4