Although the Del Amo and Montrose sites are two separate Superfund sites, they are linked together due to their proximity (they are located adjacent to each other), and by way of the commingled groundwater contamination originating from both sites. As such, we often refer to the sites as the “Del Amo/Montrose” sites because the highest priority component of the cleanup is the groundwater. However, there are other aspects (Operable Units, or OUs) specific to Del Amo and Montrose.
What’s going on at the Del Amo site?
- Currently at the Del Amo site, the EPA is conducting a Five Year Review for Del Amo OU 1 (On site soils and NAPL, or Non Aqueous Phase Liquids), OU 2, the Waste Pits, and OU 3- the Dual Site Groundwater. Read more about the Five Year Review here.
- In October of 2014, Montrose finished construction of an on-site groundwater treatment system intended to remediate the commingled contamination (OU 3). The system is currently not operating due to a number of reasons, paramount among these is whether the system will function according to the initial goals and objectives set forth in the 1999 Record of Decision (ROD) for this OU. The DAAC is particularly concerned about the system’s reinjection standards for a little-studied chemical called pCBSA (para chlorobenzene sulfonic acid). We need to know a lot more about this chemical and what the protectiveness is for reinjecting it back into aquifers.
- The Soil Vapor Intrusion sampling and studies are ongoing in the community due to the possibility of harmful vapors escaping from the groundwater, into the soils and coming into homes as soil gas.