Laserfiche WebLink
KITTITAS COUNTY SOLID WASTE ON-CALL <br />CLE ELUM TRANSFER STATION TANK REPLACEMENT <br /> SEPTEMBER 2025 Trenching <br /> 312316.13 - 2 <br /> <br />SECTION 312316.13 <br />TRENCHING <br />PART 1 GENERAL <br />1.01 SECTION INCLUDES <br />A. Backfill and compaction. <br />B. Dewatering. <br />PART 2 PRODUCTS <br />2.01 FILL MATERIALS <br />A. General Fill: Non-contaminated native excavated material checked by geotechnical engineer. <br />B. Structural Fill: As specified for Base Course in Division 9-03.9(3) of the WSDOT Standard <br />Specifications <br />C. Bedding: Pea Gravel or match existing bedding as approved by engineer. <br />PART 3 EXECUTION <br />3.01 PREPARATION <br />A. Identify required lines, levels, contours, and datum locations. <br />B. Protect existing structures, fences, sidewalks, paving, and curbs from excavating equipment <br />and vehicular traffic. <br />C. Protect plants, lawns, rock outcroppings, and other features to remain. <br />D. Locate and identify existing utilities to remain as indicated on drawings and protect from <br />damage. <br />3.02 SUPPORT AND PROTECTION <br />A. Excavation Safety: Comply with OSHA’s Excavation Standard, 29 CFR 1926, Subpart P. <br />3.03 DEWATERING <br />A. Prevent surface water and groundwater from entering excavations and surrounding areas. <br />B. Dispose of water without causing surface erosion, sediment buildup, or endangering public <br />health or property. <br />3.04 TRENCH EXCAVATION <br />A. Grade top perimeter of excavation to prevent surface water collection. <br />B. General: Cut trenches neat and clean. <br />1. Slope banks of excavations deeper than 4 feet (1.2 m) to angle of repose or less until <br />shored. <br />2. Hand trim excavations and remove loose matter. <br />3. Remove large stones and other hard matter that could damage piping or impede <br />consistent backfilling or compaction. <br />C. Maintain trenches and prevent loose soil or rocks from entering. <br />D. Remove excavated material that is unsuitable for re-use from site. <br />E. Remove excess excavated material from site. <br />F. Provide temporary means and methods, as required, to remove all water from trenching until <br />directed by the Architect. Remove and replace soils deemed unsuitable by classification and <br />which are excessively moist due to lack of dewatering or surface water c ontrol. <br />G. Determine the prevailing groundwater level prior to trenching. If the proposed trench extends <br />less than 1 foot (305 mm) into the prevailing groundwater, control groundwater intrusion with <br />perimeter drains routed to sump pumps, or as directed by the Archit ect.