A historical former industrial site of 460 acres in southern California is being redeveloped. It has gone through active bioremediation in several source areas in 2 aquifers; cis-DCE, 1,1-DCA and vinyl chloride are the remaining CVOCs. A ground water extraction system keeps CVOCs from moving offsite. Some of the source areas and most other areas in between have now transitioned to MNA, and periodic reviews are required. The site went through it's 2nd review in 2020. Evaluation of MNA was complicated by changes in ground water flow direction since the last review, due to the addition or shutdown of extraction wells. However, all areas in both aquifers appear to be performing as predicted; the three primary compounds have declined in almost all wells, many below their respective MCLs.
