Laserfiche WebLink
Implementation Options <br /> The soil quality design guidelines listed above can be met by using one of the methods listed below: <br /> 1. Leave undisturbed native vegetation and soil, and protect from compaction during con- <br /> struction. <br /> 2. Amend existing site topsoil or subsoil either at default"pre-approved" rates, or at custom cal- <br /> culated rates based on tests of the soil and amendment. <br /> 3. Stockpile existing topsoil during grading, and replace it prior to planting. Stockpiled topsoil <br /> must also be amended if needed to meet the organic matter or depth requirements, either at a <br /> default"pre-approved" rate or at a custom calculated rate. <br /> 4. Import topsoil mix of sufficient organic content and depth to meet the requirements. <br /> More than one method may be used on different portions of the same site. Soil that already meets <br /> the depth and organic matter quality standards, and is not compacted,does not need to be <br /> amended. <br /> Planning/Permitting/InspectionNerification Guidelines & <br /> Procedures <br /> Local governments are encouraged to adopt guidelines and procedures similar to those recom- <br /> mended in Building Soil. Guidelines and Resources for Implementing Soil Quality and Depth BMP <br /> T5.13 in WDOE Stormwater Management Manual for Western Washington(Stenn et al., 2016). <br /> Maintenance <br /> • Establish soil quality and depth toward the end of construction and once established, protect <br /> from compaction, such as from large machinery use,and from erosion. <br /> • Plant vegetation and mulch the amended soil area after installation. <br /> • Leave plant debris or its equivalent on the soil surface to replenish organic matter. <br /> • Reduce and adjust,where possible,the use of irrigation,fertilizers, herbicides and pesticides, <br /> rather than continuing to implement formerly established practices. <br /> Runoff Model Representation <br /> All areas meeting the soil quality and depth design criteria may be entered into approved runoff mod- <br /> els as"Pasture" rather than"Lawn/Landscaping". <br /> 2019 Stormwater Management Manual for Western Washington <br /> Volume V-Chapter 11 -Page 929 <br />