The Delaware Department of Natural Resources and Environmental Control, Solid & Hazardous Waste Management Branch (SHWMB) provides the following guidance on the management of cloth wipes, including shop towels, and rags contaminated with solvents identified by the waste codes of D001 and/or F001 through F005. For these contaminated wipes, the SHWMB offers a conditional exemption from the regulatory requirements for hazardous waste, provided the below conditions are met. The conditional exemption is not applicable to cloth wipes contaminated with hazardous wastes other than the solvents identified above, cloth wipes destined for management other than laundering, nor is this conditional exemption applicable to wipes or absorbents used to contain or remediate spills of hazardous materials or wastes.
1. Solvent contaminated cloth wipes to be exempted cannot be hazardous for any other reason (i.e., the toxicity characteristics) or for waste codes other than D001 and/or F001 through F005.
2. Cloth wipes must be non-saturated, solvent-contaminated wipes, shop towels, or rags. Saturation will be determined through utilization of the Paint Filter Test (EPA SW 846 Method 9095) or the Liquids Release Test (EPA SW 846 Method 9096). Saturation may also be determined by wringing the wipe, either by hand or mechanically. If solvent drips from the rag, the rag is considered a hazardous waste. Wipes may be rung until the rag no longer contains solvents. Wringing wipes to achieve the no drip criteria will not be considered treatment. Wipes may not be (intentionally) air dried to achieve the criteria.
3. Solvent removed from the wipes must be collected and managed as a hazardous waste or re-used onsite for its intended purpose.
4. Containers holding the wipes must be labeled "Contaminated Wipes for Laundering." Once the container is filled it must be dated.
5. Containers holding the wipes must be closed, except when adding or removing wipes. As solvent rags may pose a fire hazard, ensure your onsite accumulation practices satisfy local fire codes.
6. Generators of wipes must hold a contractual agreement with a commercial laundry. The agreement must document the wipes are being laundered and the period for which the contract is active. Copies of the contractual agreement and receipts must be retained by the generator for a period of at least three years and be made available for inspection.
7. Offsite laundering - Contaminated wipes must be laundered at an offsite commercial laundry that either performs onsite treatment of wastewaters or discharges wastewaters to an offsite Publicly Owned Treatment Works (POTW). In either instance, the discharge must be regulated under the authority of a National Pollutant Discharge Elimination System (NPDES) permit.
8. Onsite laundering - Onsite laundering of contaminated wipes is permissible provided wastewaters are discharged to an onsite wastewater treatment system or discharged to an offsite Publicly Owned Treatment Works (POTW). In either instance, the discharge must be regulated under the authority of a National Pollutant Discharge Elimination System (NPDES) permit.
Facilities not managing contaminated wipes in accordance with the aforementioned procedures are subject to full regulation of the Delaware Regulations Governing Hazardous Waste.
If you have any questions, please contact the Solid and Hazardous Waste Branch at (302) 739-9403.