The Postal Service™ “Zero Discharge” policy prohibits the release of oil, grease, metals, acids, and other pollutants into outdoor drains and stormwater systems. By following these rules, employees and contractors prevent harm to rivers, streams, lakes, and coastal waters.
When washing vehicles outdoors, employees and contractors must take precautions to prevent hazardous chemicals from entering the environment and waterways. Rules for washing vehicles outdoors include the following:
n Use a dry wash or high-vapor steam technique that does not generate wash water OR use a wet wash with wash water collected, contained, or vacuumed into a tank or other container and transported off site for proper wastewater management.
n When washing vehicles in the rain, use a covered area that is protected from stormwater runoff.
n Use only vehicle wash products that DO NOT contain any USPS targeted chemicals or exhibit hazardous waste characteristics.
n DO NOT release or discharge any wash water or pollutants into stormwater systems.
USPS® sites may establish vehicle washing contracts through the Vehicles Category Management Center (CMC), using the nationally approved statement of work for vehicle washing. Contact the Vehicles CMC at vehicleCMC@usps.gov.
For more information, refer to the Vehicle Washing Requirements Environmental Compliance Bulletin/Standard Work Instruction at blue.usps.gov/sustainability/environmental/_pdf/ecb-vehiclewashing.pdf or contact your USPS Environmental Specialist at blue.usps.gov/sustainability/regional-environmental-compliance-all.htm.
— Environmental Affairs and
Corporate Sustainability, 5-14-26
