Cleaning Up California: Two Bills to Unlock Infill Housing on Contaminated Sites

California's infill housing potential is often stalled by the legacy of contamination left behind by gas stations, dry cleaners, and industrial uses—and increasingly, by toxic debris from wildfires. Two HAC-sponsored bills are moving through the Legislature this session take direct aim at the barriers that make it harder to build on these urban sites.

SB 1258 (Wiener) – Site Mitigation and Infill Housing

Thousands of sites on the state's "Cortese List" are prime candidates for infill housing, but developers face a catch-22: they must obtain a site suitability determination before accessing streamlined entitlements under SB 35/423, yet that determination can only be issued after mitigation is complete, which typically happens during construction. The result is delay, uncertainty, and projects that never get off the ground.

SB 1258 fixes this timing mismatch by allowing a project to receive its entitlement before the suitability determination is issued, while still requiring that determination before any building permits are pulled and full mitigation before a certificate of occupancy. The bill also allows AB 304-certified local health officers to oversee site mitigation, reducing bottlenecks at state agencies. As California reckons with wildfire aftermath where burned structures leave behind heavy metals, asbestos, and other hazardous materials—this framework could prove especially valuable for communities rebuilding on contaminated land.

SB 328 (Grayson) – DTSC Generator Fee Reform

A 2021 budget trailer bill replaced DTSC's tiered fee model for contaminated soil excavation with a flat $46.20-per-ton rate. The impact has been severe—fees for one San Francisco housing project jumped from $100,000 to $800,000, making otherwise viable infill projects infeasible. Fire-impacted sites face the same problem: rebuilding after a disaster often requires excavating contaminated soil, and the current fee applies regardless of how the contamination got there.

SB 328 caps the fee at $100,000 for housing projects and $250,000 for master development projects, applying only to developers who didn't create the contamination. Builders cleaning up someone else's mess—or nature's—shouldn't be penalized for it.

Together, these bills make a compelling package: one fixes the procedural timing that discourages brownfield development, the other addresses the costs that make it infeasible. Both are increasingly urgent as California confronts the contamination legacy of its worsening wildfire crisis.