US lawFederal (United States)RegulationsTitle 40 CFR — Protection of EnvironmentChapter I — ENVIRONMENTAL PROTECTION AGENCYPart 265 — INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIESSubpart K — Surface Impoundments265.22340 C.F.R. § 265.223Containment system.Last amended: 2016Year: 2026Length: 26 wordsOfficial source Cite as 40 C.F.R. § 265.223 (2026)All earthen dikes must have a protective cover, such as grass, shale, or rock, to minimize wind and water erosion and to preserve their structural integrity.Previous40 C.F.R. § 265.222Next40 C.F.R. § 265.224