7800 EVERGREEN WAY HYUNDAI O&M Manual 2025-04-28

Pollutant Control Approach: Maintain appropriate vegetation to control erosion and the dis- charge of stormwater pollutants. Prevent debris contamination of stormwater. Where practicable, grow plant species appropriate for the site, or adjust the soil properties of the site to grow desired plant species. Applicable BMPs: . Install engineered soil/landscape systems to improve the infiltration and regulation of storm- water in landscaped areas. . Select the right plants for the planting location based on proposed use, available main- tenance,soil conditions, sun exposure,water availability, height, sight factors, and space avail- able. . Ensure that plants selected for planting are not on the noxious weed list. For example, but- terfly bush often gets planted as an ornamental but is actually on the noxious weed list. The Washington State Noxious Weed List can be found at the following webpage: https://www.nwcb.wa.gov/printable-noxious-weed-list . Do not dispose of collected vegetation into waterways or storm sewer systems. . Do not blow vegetation or other debris into the drainage system. . Dispose of collected vegetation such as grass clippings, leaves, sticks by composting or recyc- ling. . Remove, bag, and dispose of class A&B noxious weeds in the garbage immediately. . Do not compost noxious weeds as it may lead to spreading through seed or fragment if the composting process is not hot enough. . Use manual and/or mechanical methods of vegetation removal(pincer-type weeding tools, flame weeders, or hot water weeders as appropriate) rather than applying herbicides, where practical. . Use at least an eight-inch "topsoil"layer with at least 8 percent organic matter to provide a suf- ficient vegetation-growing medium. Organic matter is the least water-soluble form of nutrients that can be added to the soil. Composted organic matter generally releases only between 2 and 10 percent of its total nitrogen annually, and this release corresponds closely to the plant growth cycle. Return natural plant debris and mulch to the soil,to continue recycling nutrients indef- initely. . Select the appropriate turfgrass mixture for the climate and soil type. 0 Certain tall fescues and rye grasses resist insect attack because the symbiotic endo- phytic fungi found naturally in their tissues repel or kill common leaf and stem-eating lawn insects. 2019 Stormwater Management Manual for Western Washington Volume IV-Chapter 4-Page 524