The pits house waste materials that contain dioxins, a hazardous waste material that is not water soluble and that presents a public health threat if allowed to come into direct contact with people. The armored cap is intended to prevent the materials from moving from the Superfund site into the San Jacinto River and other adjacent areas.
During a periodic EPA inspection of the armored cap in December 2015, the agency’s dive team saw what appeared to be damage in the form of displacement of the cap’s stone cover. The PRPs — International Paper and Industrial Maintenance Corp. — delineated the damaged portion and collected sediment samples from that area and from undisturbed areas to determine if there is any contamination. While the damaged areas have seen exposed waste materials, the non-damaged samples did not reveal any contamination.
The EPA is requiring the PRPs to put the area under constant surveillance and add warning buoys to the site’s boundaries. The agency is also requiring increased underwater inspections and further sampling of the site.