Industry struggles with logistics as use of ash in agricultural soil questioned
10/14/12
Concerns over what contaminants may be associated with Humboldt County's biomass industry -- and Eel River Power's plans to shutter its Scotia facility, citing reasons including regulatory uncertainty -- highlight just two sides of the challenge of tapping the region's largest source of renewable energy.
”Biomass has played a significant role in Humboldt County,” Schatz Energy Research Center senior research engineer Jim Zoellick said, adding that it currently provides about 30 percent of the North Coast's energy.
The center recently completed a draft study for the Redwood Coast Energy Authority that said North Coast biomass energy production could potentially double by 2030.
Only Los Angeles County produces more biomass -- in its case, garbage -- according to a study from University of California, Davis. On the North Coast, biomass plants traditionally burn scraps and residue from sawmills in order to generate power.
”The mill source is very dependent on the timber industry in Humboldt County -- which has been in decline in recent years,” Zoellick said.
On top of that, some timber cut in Humboldt County is shipped overseas to be milled.
Unlike sawmill residue, Humboldt County's substantial forest biomass, created at logging sites or ecological forest thinnings, is not easily accessible.
”You can only transport it so far and have it be economically viable,” Zoellick said.
Now researchers are looking at ways to process fuel materials close to the site of recovery with satellite processors in towns like Hoopa, Willow Creek and Weaverville.
”There's not a real easy and clear path to make that stuff economically viable,” Zoellick said.
Looking toward expansion can be difficult considering the challenges facing existing North Coast biomass plants.
The North Coast Regional Water Quality Control Board recently sent letters to four biomass plants in Northern California, including Blue Lake Power, Eel River Power, and DG Fairhaven Power in Samoa.
In the letters, the board expressed concerns about the management of wood ash, a byproduct of biomass energy plants that has typically been sold or given to farmers who use the ash as soil amendment, mixing it with earth in hopes of improving various properties.
Concerns about dioxins and other contaminants in ash waste led the water board to request extensive testing, due Monday. The board will review results of the testing at its December meeting.
David Leland of the water board said that dioxins can cause cancer and be transferred through food into humans.
”It magnifies up the food chain -- or has the potential to do that at least,” Leland said.
Heavy metals and changes to pH balance are additional concerns to the area's surface water and groundwater.
Humboldt Waste Management Authority interim Executive Director Patrick Owen said that if the board determines there are too many toxins in the ash waste, power plants might be forced to send the ash to landfills instead, which would dramatically drive up costs.
”That could really affect the viability of these regional plants,” Owen said.
The problem doesn't end there. Added landfill waste could jeopardize county compliance with state-mandated waste diversion. If the plants fail, biomass would be reintroduced to the waste stream.
Water Board senior engineer Mona Dougherty said regulation of the ash lapsed in recent years. It came to the board's attention again recently when citizens expressed concerns about heavy dumping of ash and contaminants.
”We decided it was time to start taking a look and see if there were any water quality issues associated with it,” Dougherty said.
Landfilling the ash is not the only option, Dougherty said. Water board staff is researching ways to reduce contaminants during the burning process.
”We might find that there's not a problem,” Dougherty said. “It's difficult to know until we see what we've got.”
California Coastal Commission planner Melissa Kraemer said her commission had been contacted by a citizen concerned about the use of the ash in agricultural lands.
She said a lot of seasonal grazing lands around Humboldt Bay are wetlands, and the coastal commission determined that some heavy spreading of the ash constituted development, requiring a permit.
”I don't think our commission is really regulating the disposal of material as a soil amendment,” Kraemer said, but added that it was interested in the results of the water board's inquiries.
”Disposal can be a challenge,” Kraemer said. “Certainly if it has elevated levels of dioxin, we don't want that going into our waters and contaminating our oysters and dairylands.”
Attitudes about biomass appear cautiously hopeful. Matt Ross, speaking for Eel River Power, said local and state officials are working with the plant in hopes to reopen next year.
Management at the Blue Lake and Fairhaven plants did not respond to calls by press deadline.
