high weight of water that may break posts of weaker construction or less frequent spacing. In another example, a compost filter sock installed with a 3-inch (76-mm) installation trench may provide better soil retention than a compost filter sock with no installation trench. Since the effectiveness of SRDs is installation dependent, this test method is indicative of actual field performance when installed with the appropriate techniques. D7351 apparatus and procedures The test method is commonly executed using the following equipment: * A mixing tank with an internal paddle mixer device mounted on scales * A sufficient source of water and associated pumping equipment to fill the mixing tank in a timely manner * A collection tank mounted on scales of sufficient volume to accommodate all runoff passing the SRD Keystone Compac® Keystone Retaining Walls The mixing and collection tanks are separated by areas, or zones, as shown in Figure 4. A nonpermeable slope surface immediately below the mixer discharge spreads the initial discharge and provides a retention zone above the installation zone. The installation zone is comprised of prepared soil subgrade to allow fullscale installation of the SRD to be tested. Regal Stone Pro® The area below the installation zone is The combination of geogrids and Keystone units provides a proven nonpermeable to facilitate efficient transintegrated wall system. Keystone segmental walls economically offer mission of runoff passing the SRD to the structural stability, durability, and a wide range of aesthetic options. collection tank. A representative sample of the SRD to be tested is installed in the installation zone in accordance with the manufacturer's recommendations. A sediment-laden runoff is then created by combining water and soil in the mixing FebMar_2021_KRW_Geosynthetics_4.5x7.5.indd 1 12/30/20 tank and maintaining agitation during the test. A typical " construction phase " sediment concentration for testing is 6%. The rationale for the " construction 11:30 AM www.GeosyntheticsMagazine.com 25https://www.keystonewalls.com http://www.GeosyntheticsMagazine.com