The California Air Resources Board is the group that approves "prescribed burns" in California. You can read about them at https://ww2.arb.ca.gov/our-work/prog

The California Air Resources Board is the group that approves "prescribed burns" in California. You can read about them at https://ww2.arb.ca.gov/our-work/programs/prescribed-burning https://ww2.arb.ca.gov/our-work/programs/prescribed-burning, and see a map of upcoming & recent burns. Note that for the map, you'll want to drill down into "Fire Locations", then "Prescribed Fire Ignitions", and select the appropriate boxes. For example, over the past week Lawrence Livermore National Lab has had controlled burns taking place in the East Bay between Interstate 580 and Alameda County Highway J2.