CA AB2205

Expands the definition of waste from extraction, beneficiation, and processing of ores and minerals to include spent brine solutions used to produce geothermal energy under specified conditions.

Requires spent brine solutions transferred via closed piping to adjacent facilities for mineral recovery to comply with federal standards (40 CFR 261.4(a)(17)(i)-(iii)) and be returned through closed piping after processing.

Exempts geothermal waste from drilling operations and non-drilling geothermal energy production from hazardous waste requirements if contained within piping systems, trenches, or lined surface impoundments at the generating plant.

Establishes that geothermal waste exemptions expire 18 months after a power plant ceases production or a surface impoundment stops receiving waste, unless the operator submits written notification and receives department acknowledgment of intent to resume operations.

Excludes solid or semisolid hazardous residuals (including filter cakes) and wastes not directly associated with geothermal energy production from the exemption.