On August 4 of this year, the State Water Resources Control Board (SWRCB) adopted General Waste Discharge Requirements for Composting Operations under Order WQ 2015-0121-DWQ. The General Order covers most facilities that receive and process organic material including leaves, landscape trimmings, grass, food scraps, and food contaminated paper to create compost. Composting operations play an important part in the waste management hierarchy in California by helping to keep organic material out of landfills where organic material breaks down to form methane, and powerful greenhouse gas.
Composting operations can also help the State meet its goal to achieve 75 percent recycling by 2020 as established by AB 341 in 2011. In response to AB 341, the California Department of Resources Recycling and Recovery (CalRecycle) developed a plan to increase the diversion of compostable materials. The number of composting operations in California will likely increase significantly in order to achieve this statewide goal. Historically, these facilities have been regulated by the Regional Water Boards under individual WDRs or conditional waivers of WDRs. The General Order for composting operations is intended to provide a more streamlined permitting process while protecting water quality.
Which facilities are covered by the General Order?
The new General Order applies to both new and existing composting facilities, but most small composting operations (<500 cy) including backyard composting and community gardens are exempt. Composting facilities covered by individual WDRs are able to continue discharging under that authority until those orders expire or come up for renewal. Some facilities that are unlikely to degrade water quality are also exempt, such as chipping and grinding operations. It is important to note that this General Order is not a National Pollutant Discharge Elimination System (NPDES) permit. For composting operations where storm water discharges off-site, the facility may be required to enroll under the SWRCB new Industrial General Permit (2014-0057-DWQ).
How do composting operations affect water quality?
Traditional composting methods utilize windrows on open, uncovered land with material exposed to precipitation. The liquid created from excess moisture in the piles is called leachate. Depending on the materials composted, leachate can contain a wide variety of pollutants, such as nitrogen, phosphorus, metals, pathogens, and oxygen reducing compounds, which can potentially degrade water quality if they come into contact with surface waters or groundwater.
What are the new regulatory requirements in the General Order?
The proposed General Order provides a number of requirements, including standards for the permeability of the ground underneath the composting piles, drainage, and specifications for leachate collection and containment. The General Order will also include changes to requirements for monitoring and reporting. Facilities will be classified into two Tiers, based on facility size and feedstock. Specific regulatory requirements are based on the designated Tier. Some of the key requirements include:
To learn more, give us a call at 562-495-5777 or email Jacqueline.McMillen@altaenviron.com