Waste Pits cap needs major repair

Articulated Concrete Block Mat is the current solution for sealing the toxic waste under the cap.
Articulated Concrete Block Mat is the current solution for sealing the toxic waste under the cap.

HIGHLANDS – Members of the San Jacinto River Coalition learned at a meeting last month that major repairs were needed to the northwest corner of the Waste Pits site and its cap.

The meeting was held Tuesday, June 4th at the Community Center. THEA director Jackie Young led a review of the EPA Update meeting that was held May 7th in Highlands, and then brought the group the latest news on work being conducted at the site.

Construction equipment including several cranes, trucks, cement mixers, formwork and a work crew of about 15 can be seen from a safe distance, working on the placement of a new technique known as Articulated Concrete Block Mat or (ACBM).

The EPA is calling this current work “Slope Enhancement” and says it will take about a month to complete. They said that this method has key benefits over the method used before, which was a textile membrane held in place with a rock cover. This method proved to be unstable, and not a reliable method of sealing the waste material. This is the third time that major repairs were required on the cap. Work was also done in July 2018 and November 2018, but this is the first time that the ACBM technique has been used. The cap was constructed in 2011, and has a history of unreliable performance.

In updating the status of the Superfund site, Jackie said that Phase 1 Pre-Design Investigation had been completed. This including refining the volume of waste, evaluating disposal options, assessing the construction approach, and study of groundwater migration into the site.

Phase 2 will include a Pre-Design phase similar to Phase 1 but refined, a Treatability Study of the materials and methods, and then a Remedial Design with construction plans to implement the remedy.

Jackie reported on a meeting with EPA about Community Concerns, and noted these five areas:

— Health

— Cleanup

— Community Involvement

— Wildlife

— Watershed

Part of the Phase 2 work will be to classify the type of waste in the pits. Guidelines call for it to be either hazardous or non-hazardous, and which choice will have a bearing on how it is removed, and where it can be disposed of.

Jackie is concerned that tests so far have not classified the material as hazardous, but she says the tests are incomplete and not looking for dioxin and furans. Jackie displayed a chart showing characteristics of the two classes of waste. Hazardous wastes have ignitability, reactivity, corrosivity, or toxicity.

To protect the community and the disposal area, she claims that the waste must be classified as hazardous and the disposal method design based on this information.

Another issue that was discussed was the location of the orange marker buoys meant to keep barge and tugboat traffic away from the Superfund site. Conditions at low tide have revealed that the marker buoys are not far enough out to keep water traffic safely away. EPA said they moved them on the eastern portion in February 2019 in response to citizen complaints, but will extend them farther out on the rest of the cap site.