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ameO <br /> the CERTIFYING ENGINEER to facilitate hydration of the GCL upon placement. At completion <br /> of this activity, no wheel ruts, footprints, or other irregularities shall exist in the subgrade. <br /> Protrusions extending more than one-half inch (0.5 in) from the surface shall be either removed, <br /> crushed,or pushed into the surface with a smooth-drum compactor. <br /> C. On a continuing basis, the CQA Monitor and INSTALLER shall observe acceptance of the <br /> subgrade prior to GCL placement. Thereafter, it shall be the INSTALLER's responsibility to <br /> indicate to the CQA Monitor any change in the condition of the subgrade that could cause the <br /> subgrade to be out of compliance with any of the requirements listed in this Section. <br /> 3.05 ANCHORAGE <br /> A. The end of the GCL roll shall be placed in an anchor trench at the top of the slope or an equivalent <br /> runout design shall be utilized. When utilizing an anchor trench design,the front edge of the trench <br /> should be rounded so as to eliminate any sharp corners. Loose soil should be removed from the floor <br /> of the trench. The GCL should cover the entire trench floor but does not extend up the rear trench <br /> wall. <br /> 3.06 SEAMING <br /> A. The GCL seams are constructed by overlapping adjacent panel edges and ends. Care should be taken <br /> to ensure that the overlap zone is not contaminated with loose soil or other debris. <br /> B. Longitudinal seams should be overlapped a minimum of six(6) inches for Bentomat ST, or per the <br /> MANUFACTURER's recommendations for an approved equivalent GCL. If the GCL is <br /> manufactured with a grooved cut in the nonwoven geotextile that allows bentonite to freely extrude <br /> into the longitudinal overlap, then no bentonite-enhanced seam is required for this overlap. If the <br /> GCL does not have a grooved cut in one of the nonwoven geotextiles in the longitudinal overlap, <br /> then longitudinal bentonite-enhanced seams are required as described below. <br /> C. End-of-roll overlapped seams should be constructed with a minimum overlap of twenty-four (24) <br /> inches for Bentomat ST, or per the MANUFACTURER's recommendations for an approved <br /> equivalent GCL. Seams at the ends of the panels should be constructed such that they are shingled in <br /> the direction of the grade to prevent the potential for runoff flow to enter the overlap zone. <br /> D. Bentonite-enhanced seams are constructed between the overlapping adjacent panels described above. <br /> The underlying edge of the longitudinal overlap is exposed and then a continuous bead of granular <br /> sodium bentonite is applied along a zone defined by the edge of the underlying panel. A similar bead <br /> of granular sodium bentonite is applied at the end-of-roll overlap. The granular bentonite shall be <br /> applied at a minimum application rate of one quarter pound per lineal foot(0.25 lb/ft). <br /> 3.07 DETAIL WORK <br /> A. The GCL shall be sealed around penetrations and embedded structures embedded in accordance with <br /> the GCL MANUFACTURER recommendations. <br /> B. Cutting the GCL should be performed using a sharp utility knife. Frequent blade changes are <br /> recommended to avoid damage to the geotextile components of the GCL during the cutting process. <br /> Section 02776.2 Page 6 of 7 May 9,2012 <br /> Geosynthetic Clay Liner(GCL) Revision 1 <br />