Casmalia Resources is a superfund site located at Ntu Rd-539 San Ysidro Rd, Casmalia, CA 93429. The Environmental Protection Agency (EPA) identifies sites such as Casmalia Resources because they pose or had once posed a potential risk to human health and/or the environment due to contamination by one or more hazardous wastes. Casmalia Resources is currently registered as an Active NPL superfund site by the EPA. Because it is on the NPL (National Priorities List), Casmalia Resources is considered one of the worst hazardous waste sites identified by the EPA.