La Canada Unified School District and a group of concerned parents are pursuing legal strategies to challenge the massive sediment removal project at Devil’s Gate Dam in Pasadena located across the street from La Canada High School.

They say hundreds of dump trucks per day would emit diesel particulates that would endanger student health.

The Arroyo Seco Foundation and the Pasadena Audubon Society challenging the Los Angeles County Department of Public Works project have already filed two lawsuits. The parents group would weigh in and offer supportive evidence, said attorney Mitchell Tsai.

“They bring some very serious issues to the table, including recent studies that say it will increase their cancer risk,” said Tsai, a Pasadena-based environmental lawyer representing the two plaintiffs.

The La Canada Unified School District is also engaging an independent environmental consultant, said Superintendent Wendy Sinnette.

“They will look at the Health Risk Assessment that incorporates new science that our parents have brought forth.”

The schools have not been involved in previous lawsuits.

At the Dec. 5 informational meeting, several residents whose day jobs involve studying the health effects of diesel particulates or PM pollution — and whose children attend La Canada High — spoke about exposure risks at LCHS and other nearby schools and camps operating within a half-mile radius of the trucks.

Both Heather Wipfli, a researcher at the USC Keck School of Medicine, and Elizabeth Krider, a scientist at Caltech in Pasadena, quoted EPA and World Health Organization statistics that say breathing in diesel fumes can damage lungs, cause asthma, COPD, lung cancer and reduce lung growth in children.

“This is a call to action for parents, our youth and for our schools, ” Wipfli told a crowd of about 200 gathered at the high school auditorium.

10 years in the making

For the past 10 years, the county has been preparing for one of the largest sediment removal projects in its history, from one of the oldest dams in the county..

After redoing an environmental impact report deemed inadequate by the court as a result of the original lawsuits, the county won approval from the Board of Supervisors last year for a scaled down project that will take 1.7 million cubic yards of sediment from the natural area for the next four years.

The scraping of the 70-acre maintenance area of dirt, trees, muck and debris begins in April, and will take four years at a cost of $66.7 million.

The removal will fill 425 diesel dump trucks a day that will enter the Hahamongna Watershed Park and exit by the high school to dump their loads in inert landfills in either Sunland or Irwindale.

While the county has gone to great lengths to adjust truck routes away from the high school, a person standing on Oak Grove and Berkshire Place will see a truck pass by up to 850 times (two times 425 round trips) in about 8.5 hours between June and August, according to the EIR from the project.

Starting in April through the first week of June and mid August through October or November, trucks will enter and exit east of the school at Arroyo Boulevard and Windsor Avenue in the morning, to avoid school and JPL traffic.

Sediment from the upper Arroyo Seco watershed north of NASA-JPL aggregating behind Devil’s Gate Dam for 10 or more years may diminish the workings of the dam to hold back storm water, said Daniel Lafferty, assistant deputy director for the county’s stormwater planning division.

That would put more than 600 homes and businesses in the area at risk of flooding — and without a major clean out, the dam may no longer function, he said.

And, “the only option to do that is with trucks,” he said.

But the parents insist they don’t want to kill the project, just reduce the scope.

On the road inspections?

Krider said the county needs to monitor the trucks in real time to ensure pollution control equipment is working.

Recent studies by U.C. Riverside found that only two or three in-use diesel trucks out of more than 100 met the 2010 EPA standard for PM and nitrogen oxides, (NOx), a component of smog and a particle that can lodge deep in the lungs and cause disease.

“The problem is when these trucks get on the road the NOx control system doesn’t do very well,” she said, “even though they are certified when they leave the manufacturer.”

In July, the EPA recalled 500,000 diesel Cummins medium- and heavy-duty trucks that were polluting the air above the standards. Road tests revealed massive failures with on-board pollution control devices.

The company’s own testing showed “deteriorating components” that caused emissions to exceed federal and California air pollution standards, according to the EPA.

Rather than testing the trucks, Lafferty said the county would rely on the manufacturer’s specifications and spot checks by air pollution agencies.

He also ruled out trucks running on compressed natural gas or battery power as too expensive and not feasible.

Kerjon Lee, county spokesman, said the county’s contractor, Griffith Co., will use “the lowest emission diesel trucks currently in production.”

If no changes are made, the school district may close summer school at the high school and transfer the program to Foothill Intermediate School. But that option is fraught with logistical problems, Sinnette said.

The district is also adding advanced filters to high school classrooms, she said.