(1) Nothing in this chapter shall be construed as superseding, amending, or modifying the mineral processing waste exemption provided in 40 CFR 261.4(b) (7) and IDAPA 58.01.05.005, for process wastewater and phosphogypsum from phosphoric acid production.
(2) Nothing in this chapter is intended to supersede or modify any existing agreement with or approvals from the environmental protection agency or the department of environmental quality relating to the construction of a phosphogypsum stack, phosphogypsum stack system, or component thereof.
(3) The requirements in sections 42-1710 through 42-1721, Idaho Code, shall not apply to phosphogypsum stacks and phosphogypsum stack systems.
(4) This chapter establishes minimum design and construction requirements to ensure that phosphogypsum stack system impoundments meet critical safety standards and do not cause unplanned releases into the environment.