Laserfiche WebLink
DIVISION 2 - SITE WORK <br />SECTION 2310 - SLURRY WALL <br />PART 1 - GENERAL <br />1.01 SCOPE OF WORK <br />This work includes, but is not limited to: 1) preparation of native soils & construction of working surface; 2) <br />preparation, placement, and cleaning of slurry; 3) excavation of slurry trench; 4) stockpiling; 5) sand and <br />sediment removal from the slurry trench bottom; 6) cobble and boulder removal; 7) supplying, hauling, <br />blending, and placing all backfill materials temporary; 8) permanent treatment of the top of the slurry wall; 9) <br />disposal of excess slurry; and 10) quality control testing. <br />1.02 DEFINITIONS <br />A. Bentonite. An ultra fine natural clay whose principal mineral constituent is premium-grade sodium <br />cation montmorillonite. <br />B. Groundwater Level. The surface elevation of naturally occurring groundwater when subjected to <br />atmospheric pressure. Water may be perched in discrete areas at elevations higher than the <br />general groundwater level. <br />C. Fines. Fine grained soil particles, smaller than No. 200 U.S. Standard Sieve size. <br />D. Probing for Inspection, The lowering of an approved sounding instrument or appropriately marked <br />device to demonstrate the depth of the trench and the trench bottom conditions. <br />E. Remote Mixing Area. A temporary working surface constructed at a remote location from the slurry <br />wall alignment in which the soil bentonite backfill will be proportioned and mixed. <br />F. Slurry. A stable colloidal suspension of hydrated bentonite in water. <br />G. Slurry Ponds. Ponds constructed for the purpose of storing mixed slurry. Earthwork for slurry ponds <br />must consist of fill only - excavation into the existing surface will not be permitted, unless approved <br />on a case-by-case basis by the Owner/Engineer. <br />H. Slurry Trench. A vertical trench excavation, at least 3 feet wide, full of bentonite slurry to support <br />the trench sidewalls. <br />1. Slurry Wall. A semi-impervious barrier of blended soil and bentonite, at least 2 or 3 feet wide, with <br />a hydraulic conductivity of 1 x 10-6 centimeters per second (cm/sec) or less, constructed using a <br />slurry trench during excavation and backfilling. <br />J. Working Surface. The prepared temporary working surface (pad) from which the slurry trench <br />excavation, backfill mixing, and backfilling operations are performed. <br />1.03 SUBMITTALS <br />A. Preconstruction. The Contractor shall submit the following items for approval to the <br />Owner/Engineer at least 10 working days prior to commencing the Work: <br />1. Bentonite Certification. A Certification of Compliance including test results from the <br />bentonite supplier that each shipment of the bentonite meets the requirements of the <br />Specifications and is in compliance with American Petroleum Institute (API) Standard <br />13A. The sources for all bentonite shall be included with the Certificate of Compliance. <br />2. Sample. Forty pounds of the proposed powdered bentonite. <br />3. Identification of Water Source. Name of water source and provide chemical analysis, if <br />source is other than potable water collected from a municipal hydrant.