Rangers said the search was difficult because the area had been hazardous since the runoff of Hurricane Floyd five months ago, and had been made more dangerous by snowstorms and thawing that created shelves of unstable snow.
"For every million tires consumed by fire, 55,000 gallons of runoff containing hazardous materials is created, and tire fires can produce 32 different toxic gases," he said.
Granted, it is possible to cross to the east JPL lot by way of an informal route that heads straight across the Arroyo, but this other trail crosses the Arroyo by way of an un-maintained ford that is passable when dry but has been hazardous during any time of heavy rain and runoff.
The microbes contribute to the highly acidic runoff that has made the mine a major hazardous waste site under the federal Superfund program.
Even the runoff water from fighting such fires can be filled with hazardous chemicals, said Bob McCarthy, a researcher at the agency.
The Army Corps of Engineers estimates that removing the MTA tag from the river alone will cost $3.7 million because hazardous materials crews must create an elaborate dam to capture all the paint and runoff water so it doesn't get into the riverbed.
Some hazardous materials did escape, and firefighters and technicians from the Orange County Health Care Agency were checking the fire water runoff in the first-floor and basement for contamination, Summer said.
The marshes could also be dying from pollutants: highway and asphalt runoff soaked with motor oil and diesel fuel; toxins leaching from three inactive hazardous-waste landfills; and raw sewage overflowing from wastewater treatment plants.
Mine workers are potentially subject to dangerous conditions, including exposure to hazardous gases, radioactivity exposure, loss of power (in particular in underground mines), collapsing tunnels, dust inhalation and toxic runoff (see Human Rights Violations page).
