LANDSCAPE WASTE COMPOSTING
CASCO, MI
In July of 2015, ASTI Environmental was retained by landscape waste composting facility to prepare a Spill Prevention, Control and Countermeasure (SPCC) and Storm Water Pollution Prevention (SWPP) Plan for the yard waste composting facility in Michigan. ASTI was also retained to perform an evaluation of methods to reduce the Escherichia coli (E. coli) bacteria in the contact storm water (storm water that contacts the yard waste and compost) pond. ASTI performed a site assessment and worked with the client to develop a list of necessary plans, permits, and programs and a timeline for achieving compliance with all applicable state and federal regulations.
ASTI developed a Spill Prevention, Control and Countermeasures (SPCC) Plan for the facility to comply with federal (Oil Pollution Act) and state (Michigan Part 5) spill prevention planning requirements. ASTI concluded that without treatment, storm water could not leave the site without contaminating the receiving waters, and in the event of a large storm the current storm water facilities could not retain all of the storm water, The was a significant risk of accidental discharge of contaminated water was. To solve this problem, ASTI engineers designed a self-sustaining retention pond. The existing pond area would have to be expanded to achieve a water depth of six inches that would allow for plant growth to absorb nutrients and maximizing evapotranspiration. These measures would make the pond sustainable; storm water would not be discharged from the site and excessive quantities of water would not accumulate. The pond design also included an increased depth of free board, the vertical depth in the pond above the maximum water elevation to ensure that a storm event greater than the 100 year storm would not cause an accidental release of storm water.
ASTI compared various treatment technologies for E. coli bacteria such as aeration, filtration, ultra-violet light treatment, constructed wetlands, and others. The advantages and disadvantages of each, their respective efficiencies and estimated post-treatment E. coli concentrations, size and area required, and general cost estimates were evaluated and presented to the client. ASTI reviewed Michigan’s Water Quality Standards (WQS) for microorganisms and concluded that the E. coli concentrations in both the storm water collection system are well above standards for total body contact. ASTI suggested managerial and structural treatment methods to the client. ASTI’s final recommendation was to retain the water on site in the proposed expanded retention pond because it would not be cost effective to treat the water to acceptable levels.
ASTI continues to provide environmental services to Indian Summer Recycling.