You must close the storage and treatment units in a manner that:
(a) Minimizes the need for further maintenance; and
(b) Controls, minimizes, or eliminates, to the extent necessary to protect human health and the environment, post-closure escape of hazardous waste, hazardous constituents, leachate, contaminated run-off, or hazardous waste decomposition products to the ground or surface waters or to the atmosphere; and
(c) Meets the closure requirements of this subpart and the requirements of Sec. Sec. 267.176, 267.201, and 267.1108. If you determine that, when applicable, the closure requirements of Sec. 267.201(tanks) or Sec. 267.1108 (containment buildings) cannot be met, then you must close the unit in accordance with the requirements that apply to landfills (Sec. 264.310). In addition, for the purposes of post-closure and financial responsibility, such a tank system or containment building is then considered to be a landfill, and you must apply for a post-closure care permit in accordance with 40 CFR part 270.