Notwithstanding Chapter 2001, Government Code, and any other provision of this chapter, the commission shall grant to the owner or operator of a commercial hazardous waste disposal well facility originally permitted after June 7, 1991, a permit modification that authorizes the construction and operation of an on-site or adjoining landfill for the disposal of hazardous and nonhazardous solid waste generated by the operation of the facility if the proposed landfill meets all applicable state and federal design requirements and the commission follows a public notice and comment procedure that is consistent with 40 C.F.R. § 270.42.