A hazmat team sifts through piles of ash on their hands and knees, slowly, methodically. They poke and prod mounds of debris with a shovel. They were tasked by the Environmental Protection Agency (EPA) to examine what is left of Altadena, a neighbourhood destroyed by the fires that razed parts of Los Angeles County last month. The crew wears jumpsuits and gas masks while they look for pesticides, paint cans and propane tanks—anything toxic or prone to explode. They avoid walking near chimneys, which are often the only things left standing on incinerated lots. They could topple over at any minute. To the north, the charred mountains loom.