The new plant is a replacement for a standard package plant which was installed at the site, and the analysis makes clear why the package plant doesn't work. The effluent at the site is simply nothing like the domestic sewage such plants are designed to treat.
Package plants don't like fats, oils, and greases, nor do they like detergents, biocides, or other inhibitory chemicals. They really only like domestic wastewater. Mostly sewage, with a bit of bathwater, and some laundry. Lab wastes are not really their thing.