120 likes | 246 Vues
This document outlines Minnesota's compost regulations as managed by the Minnesota Pollution Control Agency, focusing on various compost facilities, including backyard, yard waste, and source-separated organics (SSO) sites. It details requirements for permitting, acceptable materials, operational practices, pathogen reduction, and testing protocols for finished compost. Proposed amendments include redefining backyard compost exemptions and clarifying conditions for SSO facilities. The goal is to enhance public health and environmental safety while promoting effective composting practices.
E N D
Minnesota Compost Rules Ginny Black Source-separated Organics Coordinator Minnesota Pollution Control Agency March 2013
Current Rule • Backyard, exempt • Yard Waste, permit by rule (121) • Solid Waste Compost Facility, full permit • 9 facilities • 5 - significant public investment • 3 - private (one new and not operating yet) • 1 - native community – Mdewakaton Sioux • Capacity: 330,000; Generation 650,000 (metro only)
Proposed Amendment to Compost Rule • Changing Backyard compost exemption to a Small Compost Site exemption • Source Separated Organic Materials compost facility
Small Compost Sites • Under 80 cubic yards, excluding finished compost • Acceptable materials: food scraps, yard waste, poultry litter generated on site, non-recyclable paper, compostable plastics (ASTM D6400 or D6868 • Unacceptable Materials: fats, oils, grease, meat, dairy, animal manure, diapers , sanitary products • Managed to avoided nuisance and public health risks
Yard Waste Compost Facility • Yard waste ban 1990/92 • Permit by rule process • Process to Further Reduce Pathogens • Requires period turning (3-5 times in 21 days) • Maintain temperatures - 131 degrees F • Less than 3 percent inerts, < 4mm • Control run-off/run-on • Testing of finished product not required • Unlimited use of finished product • Annual report
Source-separated Organics (SSO) Compost Facility Concept • New facility feed stocks: • Yard waste • Wood waste • Food waste • Industrial/manufacturing food residual – human food production • No fish waste, animal waste, meat by-products generated from industrial sources, sanitary products, diapers, sewage sludge, biosolids, septage
SSO Compost Facility Concept Pad Design • Hard packed all weather surface (tipping/mixing, active, curing and finished storage area) • 5’ to water table • Any combination of the following soils: • Sandy clay loam, loam, silt loam, silt, sandy clay loam, clay, silty clay • Pad: 1’ low permability soils (tipping/mixing, active) • < 5’ from water table • Low permeability soils meeting MNDOT specs for surface aggregate • Other: concrete, asphalt or geomembrane • Only under the tipping/mixing and active compost area (PFRP) • All weather drivable surface in curing and finished storage area)
SSO Compost Facility Concept • General Ops requirements • Secure site/signage • Secures recyclable materials, trash, rejects • Process to Further Reduce Pathogens requirements • Windrows: 21 days at 55° C, turn every 3-5 days • Static aerated pile: 7 days at 55° C • In-vessel: 3 days at 55° C • Feed stock management plan • Contact/Storm Water Management plan • NPDES standards must be followed • Odor minimization plan
SSO Compost Facility Concept • Training plan • 24 contact hours of training within 12 months of employment, then every 5 years • 5 contact hours every year • Acceptable list of courses approved by the Commissioner • Contact hour = 50 minutes
Solid Waste Compost Facility • MSW feedstocks, manures, biosolids….. • Controlled access points • Training plan • Designated delivery area • 10-7 pad for tipping/mixing/active compost area/curing area • Leachate/storm water management systems • Salvageable/recyclable materials properly stored and removed weekly • Residuals properly stored and removed weekly • Meet PFRP • Windrows: 21 days at 55° C, turn every 3-5 days • Static aerated pile: 7 days at 55° C • In-vessel: 3 days at 55° C
Finished Compost Testing • Testing required • 503 metals test • pH • Particle size • NPK • Soluble salts • Maturity – some flexibility • Fecal coliform, E. coli • PCB • Class I: ≤ 503 metals standards • Class II: ≥ 503 metals standards.