275. On-site wastewater treatment plant sludges which may contain trace amounts of Section 313 toxic chemicals are composted on-site on concrete pads. The finished compost is then used as daily cover for the on-site sanitary landfill and for landscaping around the site. Is this considered land treatment, land impoundment, or not a release?
Some listed toxic chemicals in the composted material may degrade such that the chemical is treated for destruction in the compost. In those cases, the listed toxic chemical should be reported as treated on-site (in Part II, Sections 7A (On-site Waste Treatment and Efficiencies) and 8.6 (Quantity Treated On-site)). If the listed toxic chemical is not destroyed, the amounts applied to the on-site sanitary landfill as cover should be reported in Part II, Section 5.5.1B (Other Landfills) and in Section 8.1a (Quantity Released) on the Form R. Although any quantities used as landfill cover would not be exempt from reporting, the amount used for landscaping on-site is exempt under the facility grounds maintenance exemption (40 CFR Section 372.38(c)(2)).