Burn Dump neighbors’ study refutes city’s
Contractors hired by the city indicated that the defunct dump off Highway 32 near Bruce Road, which had been used until 1964 as a city-county dumping ground for everything from household garbage to toxic industrial waste, could be safely “capped,” thus opening it to residential building.
But an investigation by toxicologist Norman Ozaki of the SOMA Corporation questioned the methods and finding of the city’s studies. If the city’s studies are off base, the risk of exposure to such toxic substances as lead and arsenic through airborne dust could be worse than anticipated.
SOMA was hired by the California Park Homeowners’ Association, whose members live downwind of the dump, which also sits very near Marsh Junior High School. The association’s concern is that, if the dump isn’t left as it is, the work needed to excavate some of the soil and cap the rest could stir up dioxins, polycyclic aromatic hydrocarbons (PAHs), arsenic and lead.
At a March 20 meeting of the Humboldt Road Burn Dump Committee, James Embree, principal toxicologist for Geomatrix Consultants, showed up to refute the six-page SOMA report. But some concerned neighbors, such as Julie Nasr, had hoped to hear from a toxicologist from the state Department of Toxic Substances Control, mainly because Geomatrix is a subcontractor to the city-hired EMKO Environmental, Inc. and may have an interest in sticking by the findings.
Ozaki’s report took issue with the methods used by Geomatrix in evaluating how much dust would be stirred up during capping efforts and what potential health risks those could pose if inhaled, touched or eaten. He called the dust-related risk assessment “inadequate.”
“The use of a 50-percent reduction factor is arbitrary and has no basis in science,” Ozaki claimed, referring to the industry standard that assumes half of the dust is certain not to drift off-site. “Deposited dust could remain in the environment as well as in homes for years.”
Ozaki also wished the study had addressed such things as exposure to people driving by on Bruce Road during remediation, along with the risk to on-site construction workers.
He was particularly concerned that Geomatrix didn’t include in its calculations the results of an earlier city-commissioned study by Metcalf & Eddy, Inc. But Embree said the 1993 report, including its findings of higher concentrations of lead (a carcinogen), is not relevant.
“The risks for this site are low to begin with,” Embree said, and to do a larger assessment would be unnecessary and cost much more.
At the meeting, Embree set about addressing 25 contentions by Ozaki but got only to No. 9 when, three hours into the meeting, the committee decided to invite him back to continue March 27 at 4 p.m. in Conference Room 2 of the Council Chambers building.