Toxic waste lurking in the soil under West Oakland neighborhoods is the next environmental threat in this community already burdened by pollution. The stability of buried contamination from Oakland’s industrial past relies on it staying in place in the soil. But once the rising waters of San Francisco Bay press inland and get underneath these pockets of chemicals and gases, a certain amount of that waste will not stay in place. Instead, it will begin to move. More than 100 sites — colorless gases in dirt under schools, flammable chemicals buried in shallow soil near parks, petroleum in pockets of groundwater from iron manufacturing — lie in wait.