Devil’s Gate work halted for dust issues, project cited 3 times by AQMD

A truck creates dust as it passes over exit grates while heading out of Hahamongna Watershed Park near La Cañada Flintridge in July. The county’s sediment removal project was halted Sept. 5 to allow for dust mitigation improvements just weeks after the project received three citations for dust and dirt tracking violations.
(Raul Roa/Staff Photographer)

La Cañada residents have gotten a temporary reprieve from sediment hauling at nearby Devil’s Gate Dam, after county officials halted the project last Thursday to address issues related to fugitive dust and dirt tracking outside the site.

Los Angeles County Public Works Assistant Deputy Director Steve Burger confirmed operations have paused to allow for the installation of dust mitigation measures beyond the street sweepers, water-spraying measures and single tire-wash station already employed.

“Hauling was suspended due to dust and mud that was observed on the tires of trucks leaving the reservoir, even after the tire wash was established,” he said in an email Tuesday. “Public Works is working with the contractor to develop a plan that includes running at least two tire washes in a series.”

Burger estimated hauling could resume by the end of this week or early next week but would not begin until the county was “confident that the best possible measures are in place to mitigate dust from the tires.”


News of the stoppage comes 71 hauling days into the four-year project, which has so far seen diesel trucks haul away some 360,000 cubic yards of sediment in 24,818 truck trips, according to county figures.

Although La Cañada residents and officials overseeing schools near the dig site were primarily concerned about diesel truck emissions, the observance of dust and complications with efforts to water down the project site, trucks and nearby roads have constituted the bulk of complaints so far.

And the South Coast Air Quality Management District, which is overseeing environmental impacts at the site, concurs. Last month the project was cited three times by agency officials for violations pertaining to dust and dirt tracking resulting from insufficient mitigation efforts, according to spokesman Bradley Whitaker.

On Aug. 1, AQMD observed “visible dust emissions caused by the failure to sufficiently water the exit ramp of the site and visible dust that crossed the property line,” in violation of the agency’s fugitive dust rule, and issued a citation to county contractor, Griffith Co.


The second notice of violation occurred on Aug. 15, when a sweeper truck operating without appropriate water spray caused a cloud of dust to cross property lines. In that case a citation was issued to subcontractor Consolidated Street Sweeping.

A third violation occurred the following day, after AQMD observed a vehicle causing more fugitive dust emissions, and a citation was issued to Griffith Co. for failing to stabilize an unpaved road using best available control measures.

Whitaker said once a notice of violation is issued, it’s referred to the agency’s legal department, where potential civil penalties and settlements are negotiated. If no settlement can be reached, a civil lawsuit may ultimately be filed in superior court, he added.

La Cañada Mayor Pro Tem Greg Brown, who’s been keeping an eye on dust emissions since the project began in late May, said while he appreciates the county’s halting the work to address fugitive dust, a solution has still not been shared with city leaders.

“It’s good news they’ve recognized the problem, but we still haven’t found the right formula for fixing the problem — that’s what needs to be done,” Brown said.

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