A bill signed by Gov. Gavin Newsom last week creates a new “idle reserve” mining category, allowing aggregate mines to remain idle for up to 25 years instead of 15, changes the test for determining “idle”, along with additional changes. This article explains what the bill, which takes effect Jan. 1, 2027, means to mine operators.
Assembly Bill 982 amends the Surface Mining and Reclamation Act (“SMARA”) to (1) create a new classification of mine status known as “Idle Reserve Mine Status,” which allows qualifying construction aggregate mines that have temporarily ceased surface mining operations and are already classified as “idle” to remain idle for up to 10 additional years before the mine must begin reclamation of the site; and (2) replace the production-based definition of an “idle” mine with an activity-based definition, applicable to any and all surface mines in the state. The law also adds the new mine statuses to the annual reports operators file and, from 2028 through 2032, and requires the Division of Mine Reclamation (“DMR”) to post each mine’s status publicly by lead agency.
AB 982 was authored by Assemblymember Juan Carrillo (D-Palmdale) and sponsored by JMM client California Construction and Industrial Materials Association (“CalCIMA). It revisits two issues the Legislature last addressed in SB 108 (2011), which refined, but ultimately retained, the production-based definition of “idle,” and SB 143 (2012), which capped the term of an Interim Management Plan (“IMP”) at 15 years. The Legislature stated its intent to “minimize the waste of construction resources, while ensuring the timely reclamation of idle construction aggregate mines, and to prevent indefinite delays in or avoidance of reclamation efforts.”
Why Mine Status Matters
Under SMARA, a mine’s status determines which regulatory track it is on. An “active” mine operates under its permit (or vested rights) and approved reclamation plan. An “idle” mine must file an IMP within 90 days of becoming idle, and the approved IMP, which is treated as an amendment to the reclamation plan, allows an operator to maintain the mine in idle status without having to commence reclamation until market demand is reestablished and the mine can be returned to active status (Cal. Pub. Res. Code § 2770(h)(1)). But the IMP currently has a more limited term. As a general rule, it may last no more than 15 years, an initial five-year term and two five-year renewals, and a mine still idle when the IMP expires must reactivate production regardless of market conditions or else begin reclamation (id. § 2770(h)(2)(A), (h)(3)). Because reclamation returns mined lands to a condition readily adaptable for alternate land uses (id. § 2733), a mine pushed into reclamation while permitted reserves remain may lose the practical ability to mine them.
A New Activity-Based Definition of Idle Mines
SMARA currently treats an operation as “idle” when production is curtailed for one year or longer by more than 90 percent of its maximum annual mineral production in any of the last five years without an approved IMP, and the operator intends to resume mining.
The result can be counterintuitive: a mine that is still mining can be “idle” because its production fell sharply from an earlier peak, such as a year spent supplying a single large project.
AB 982 replaces that production-based definition with three activity-based status definitions that apply to all surface mining operations, including but not limited to aggregate mines, subject to SMARA. First, an operation is “active” if surface mining operations occurred during the reporting year. Second, it is “idle” if it is formerly active, but “surface mining operations did not occur during the reporting year, with the intent to resume the surface mining operation at a future date.” Finally, it is “in the process of being reclaimed” if the operator has ceased surface mining operations and is implementing its reclamation plan, for the timeframe that plan or applicable permits allow. These changes are significant. For example, a mine whose production fell more than 90 percent and previously considered “idle” may now be “active.”
What Counts as “Surface Mining Operations”
Because a mine’s status under AB 982 turns on whether “surface mining operations” occurred during the reporting year, rather than on how much it produced, what that term covers takes on heightened importance. SMARA defines it broadly as “all, or any part of, the process involved in the mining of minerals on mined lands,” and, with the State Mining and Geology Board’s regulations, it reaches not only extraction but related activities such as exploration, the disposal of mining waste, and the stockpiling and recovery of mined materials (Cal. Pub. Res. Code § 2735; Cal. Code Regs. tit. 14, § 3501).
Idle Reserve Mine Status for Construction Aggregate Mines
For construction aggregate mines, the significance of Idle Reserve Mine Status is that a qualifying idle mine now may remain under an IMP for up to 25 years rather than 15 (Cal. Pub. Res. Code § 2770(h)(2)(A), (h)(2)(C)(ii)). That additional time matters because construction aggregate, such as sand, gravel, and crushed rock, is transportation sensitive and typically uneconomical to haul more than 100 miles (id. § 2770(j)). Each aggregate mine therefore largely serves a local market, and its demand rises and falls with the local economy. A mine idled by a local slowdown may exhaust 15 years of IMP time before demand returns, and must then begin reclamation even though its reserves will be needed again. Allowing these mines to ride out local economic cycles under an IMP is also better policy for the state: when demand returns, returning an existing mine from idle to active is preferable to permitting a new greenfield mine.
Under AB 982, a currently idle mine authorized to extract construction aggregate may apply for “Idle Reserve Mine Status.” DMR reviews and comments on the application, and if DMR concludes the statutory conditions are met, the lead agency may, in its discretion, extend the IMP by up to 10 years. As with an IMP, approval of Idle Reserve Mine Status is not a “project” under the California Environmental Quality Act. These statutory conditions and limits include a State Geologist finding of economically viable permitted reserves, a cap of 12 applications per fiscal year, and a Jan, 1, 2033 sunset for new Idle Reserve Mine determinations(id. § 2770(h)(2)(C)(i), (viii)). It also leaves the operator’s compliance obligations in place: the extension cannot outlast the mining permit, financial assurances must remain in effect, and a mine still idle when its IMP expires must begin reclamation (id. § 2770(h)(2)(C)(i), (h)(3)).
What AB 982 Means for Mine Operators
Fifteen years after SB 108 took an initial step toward addressing SMARA’s treatment of idle mines, AB 982 represents the Legislature’s latest effort to preserve economically viable mineral resources while maintaining a defined path toward reclamation. Its two changes work together to keep permitted reserves from being lost to reclamation simply because demand fell. Under current law, a downturn that cuts a mine’s production by more than 90 percent makes the mine idle and starts an IMP clock that can expire after 15 years, even while the mine keeps operating. Once a site is reclaimed for another use, its remaining reserves are effectively lost. Under AB 982, a mine that continues surface mining operations, even at low levels, stays active and off the IMP clock, and a qualifying construction aggregate mine that goes idle can remain under an IMP for up to 25 years, long enough to ride out a local downturn and return to active status when demand returns.
About the authors
Kerry Shapiro chairs the Natural Resources & Mining Practice Group at Jeffer Mangels & Mitchell LLP. He has represented the mining, building materials, and other resource industries on mineral extraction and land development projects for more than 25 years. Kerry also serves as General Counsel to the California Construction and Industrial Materials Association (CalCIMA). Contact him at KShapiro@jeffer.com.
Ha Chung is an environmental and land use lawyer at Jeffer Mangels & Mitchell LLP. He advises clients on land use, development, water resources, and environmental regulatory compliance matters. Contact him at HChung@jeffer.com.