A CalFire fire apparatus engineer has been arrested in Mendocino County on suspicion of setting five fires in the areas around Geyserville, Healdsburg, and Windsor. Friday, CalFire law enforcement officers arrested 38-year-old Robert Hernandez of Healdsburg at the agency’s Howard Forest station in Mendocino County. Hernandez was be booked into Sonoma County Jail on suspicion of arson to forest land.