survivors and community solidarit y. Read on to discover how these projects are using bioremediation for recovery in the aftermath of wildfires.
Butte Remediation & the Camp Fire In November 2018, the Camp Fire burned over 150,000 acres (60,000ha.) in Butte County, devastating the town of Paradise and the surrounding communities. In a fire sparked by the corporate negligence of the power company PG&E, and fueled by climate change, 86 Californians tragically lost their lives. The fire destroyed close to 19,000 structures, creating millions of tons of toxic ash and debris, full of heavy metals and toxic chemicals.
Cheetah Tchudi had been organic farming, growing mushrooms, and ranching for 13 years in Butte County when the Camp Fire destroyed his home, Turkey Tail Farm. The fire burnt down his house, greenhouses, mushroom lab, and vehicles, leaving behind burnt plastics and metals. Seeing the damage to his farm and in his community, Tchudi launched the non-profit ‘Butte Remediation’, to provide free support to his fire-affected neighbors, with soil testing and targeted mycoremediaton installations aimed at mitigating the toxic contamination left behind by the fire.
Tchudi spent considerable time fundraising to cover the expensive tests needed for the baseline soil samples at six home sites, highlighting the need for cheaper soil testing options to be available to fire impacted communities. His test results revealed high levels of some metals and also chemicals such as benzene and dioxin. Tchudi then started propagating mushrooms including oyster, turkey tail, tiger sawgill, shaggy mane and phoenix oyster mushrooms to target the contaminants he had identified, as well as help restore post-fire damaged soils. “Fungal mycelium restores porosity and improves water infiltration, which is important post-fire when soils have been baked and are not absorbing water,” explains Tchudi.
Next, Tchudi set up different mycofiltration and erosion control installations on the sites, using fungal inoculated straw wattles, jute landscape fabric, incorporated wood chips, sheet mulching, and myceliated burlap bunker bags. “After the Camp Fire, some 300,000 linear feet of regular straw wattles were deployed in Butte County, to help with erosion control and runoff,” explains Tchudi. “If we were to inoculate these wattles with fungi, we could biologically immobilize some of the metals and break down contaminants, reducing the toxicity of ash and run off from the rain events that go into our streams and waterways after the fire.”
Tchudi also experimented with remediating the contaminated soil around the burnt home sites. Using a rototiller on the site to expose the soil, he spread copious amounts of mushroom spawn, and then covered the spawn with jute landscaping fabric and straw. With some additional irrigation, he was able to get mushrooms to grow directly from the contaminated soil and ash. One trick Tchudi developed was inoculating jute landscaping fabric with fungi to create a mycelial mat that could be rapidly and easily deployed on the burn sites.
Afterwards, Tchudi tested the soil and the mushrooms for contaminants. He found his efforts had led to some reductions in copper, lead, barium, zinc, and chromium. At another site, he found a good reduction in dioxins, with an eight-fold reduction after fungal treatment. On his site with PAHs, there was also success with degradation.
Tchudi found that though soil tests showed a reduction in some of the heavy metals, no significant metal content was found in the fruiting bodies of the mushrooms, making it difficult to remove the metals from the site. “Fungi can create compartments (extra vacuoles) and store the metals in there at the mycelial level,” theorized Tchudi. “This could allow for the metal to be pulled out of the soil into the mycelium, but not effectively moving the metal into the fruiting body.”
Tchudi’s project paints a realistic picture of post-disaster mycoremediation, moving beyond the hype of mushrooms as a silver bullet, and instead working in real-time to explore both the potential and limitations of fungi in remedying post-fire toxicit y. “Mother Nature is going to come knocking at some point, and we need to have a stronger game plan,” states Tchudi. “Mycelium can be a stop gap for the spread of pollutants, and breaking down chemicals. Fungi is one of many tools in a toolbox, and we should use every tool available to protect our communities and ecosystems.”
CoRenewal & the Post-Fire BioFiltration Initiative California’s 2020 fire season proved to be the most destructive in the state’s histor y. In August, lightning strikes ignited powerful wildfires in multiple counties. The fires hit too close to home for Maya Elson, the Executive Director of CoRenewal, a non-profit organization dedicated to providing education and research in bioremediation and ecosystem restoration. “When the fires came, it became very clear it was time to mobilize. I was watching the news as my community was burning and it felt like there was no choice but to step up and do something,” states Elson. CoRenewal launched the Post-Fire Biofiltration Initiative. The goal of the project is to examine how myco-wattles (straw wattles inoculated with mushroom mycelium) placed below burned homes could reduce heavy metals and PAHs from entering waterways, while also decreasing soil erosion.
Though the project was initially started in response to the CZU Lightning Complex Fire in Santa Cruz, it grew quickly to cover four additional fire impacted counties as word spread of the effort. “One of the most inspiring things about this experience has been meeting residents who have lost so much, some having barely escaped with their lives,”
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Aluminum contamination in soil from burnt home site. Photo: Maya Elson CoRenewals’ Erica Schroeder and Maya Elson testing soil on burn site for PAHs. Photo: Maya Elson Wild native species of oyster mushroom. Photo: Taylor Bright CoRenewal volunteers installing and staking in wattle downhill on a burn site. Photo: Maya Elson