2021 Owens Corning Sustainability Report | Reducing Our Environmental Footprint | Responsible Water | 176 Discharge Compliance Owens Corning facilities comply with national, state, and local regulations and permits regarding water withdrawal and wastewater discharge. We have deployed advanced water treatment systems at our top three water-discharging facilities to ensure that the quality of the water they discharge meets or exceeds permit requirements. Our businesses use water in different regions with different regulations, and in different processes. Because of this, our approach is tailored to the site level. In applicable sites, we actively monitor relevant effluent data — including Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), and Total Suspended Solids (TSS) — and we collaborate with external organizations to verify our discharge information. Where it is necessary to meet discharge requirements, we pretreat or treat our wastewater prior to discharge accordingly. Most of our sites are charged for their water discharge, and all our sites are expected to comply with local regulations for their water discharge. In 2021, we discharged a total of 5,799,928 cubic meters, which represents a 5% improvement from the base year 2018. This includes discharges to publicly owned treatment works (POTW), surface water, off-site shipment, and other destinations. Regarding environments that are around our facilities, discharges are controlled through permits and required monitoring. Moreover, several of our facilities have achieved a zero-discharge level (other than water discharged for irrigation). Unauthorized discharges and runoff must be reported to our environmental and legal departments, and corrective action must be taken. Employees are subject to disciplinary action for knowingly failing to comply with legally required environmental reporting.  POTW 79%  Surface Water 21%  Discharge (other) <1%  Off-Site Shipment <1% 2021 Water Discharge by Destination Photo submitted by: Kelly Picking | Toledo, Ohio, U.S. Maumee Bay State Park, Oregon, Ohio, U.S.