- EEC has manufactured and installed environmental protection systems world wide, Compact Package Sewer Plants, Industrial Bio Treatment Systems, Oil Water Separators, Reverse Osmosis, MBBR, Membranes, Bio Media, Evaporators, Package Treatment WWTP, Wastewater Systems, Sequencing Batch Reactors, Close Loope Systems. Recycling Systems and Total Solution plants ...www.eecusa.com