Ariz. Admin. Code § 18-16-501
In addition to the definitions set forth in A.R.S. § 49-281, the following definitions shall apply in this Article, unless the context otherwise requires:
"Abandoned well" means a well that has been permanently sealed or closed with cement or a cement-bentonite mixture that cannot be re-entered except by redrilling the wellbore, or a well that has been formally abandoned under R12-15-816.
"Currently supplies water" means a well that supplies water at the time the request for interim remedial action is submitted to the Department. Wells that supply water as needed to meet demand, including wells that serve water on an infrequent basis, are considered to currently supply water under this definition.
"Department" means the Arizona Department of Environmental Quality.
"Interim remedial action" means an action taken by the Department or by a well owner or operator under A.R.S. § 49-282.03.
"Part of a public water system" means a well that is owned or operated by an operator of a public water system, but has not been abandoned. A well that has been capped, air gapped or closed due to contamination, but not abandoned, shall be considered part of a public water system.
"Public water system" has the same meaning as defined in 42 U.S.C. § 300f.
"Registry sites" means sites that have been investigated and placed on the Water Quality Assurance Revolving Fund registry of sites.
"Remedy" has the same meaning as defined in A.R.S. § 49-281(13).
Ariz. Admin. Code § R18-16-501