Arizona Supreme Court: San Carlos Apache Tribe v. State of Arizona, et al.
Case No. CV-22-0290-PR Filed June 27, 2024
ISSUES:
- Whether the construction of Shaft 10 at Resolution Copper’s mine constitutes a “new source” under the Clean Water Act (CWA).
- The proper framework for determining if a construction is a “new source” under the CWA.
DECISIONS:
- The Arizona Supreme Court concluded that Shaft 10 is not a “new source” under the CWA.
- The court established a three-step test for determining whether a construction is a “new source” under the CWA, based on the criteria in 40 C.F.R. § 122.29(b).
Synopsis:
The Arizona Supreme Court reviewed whether the Arizona Department of Environmental Quality (ADEQ) properly issued a water discharge permit renewal to Resolution Copper Mining, LLC in 2017. The San Carlos Apache Tribe challenged the permit renewal, arguing that the construction of a new mine shaft (Shaft 10) created a “new source” under the CWA, which would trigger additional regulatory requirements. The court established a three-step test for determining whether a construction is a “new source” under the CWA, based on the criteria in 40 C.F.R. § 122.29(b). The court found that Shaft 10’s processes were not substantially independent of existing sources at the mine site, and there was no new source performance standard independently applicable to Shaft 10.
Outcome of the case:
The Arizona Supreme Court affirmed the decision of the Arizona Water Quality Appeals Board, which had upheld ADEQ’s issuance of the 2017 permit renewal.