A local wastewater treatment plant has started having trouble meeting its NPDES limit for nitrogen. They have two identical, parallel nitrication-denitrication process trains. They both receive the same inuent, but they have separate return activated sludge lines that send sludge from their respective clariers back to the inuent of the process trains. One of the nitrogen removal trains is working (nitrogen is meeting the discharge limit) and the other isn't (nitrogen is exceeding the limit). The plant has not changed its operational procedures and all the machinery works. The plant called you to try to help them figure out what is going on. Your job is to prepare a brief (1 page) proposal describing what you would do to determine what might be happening in the process train that isn't working. Select a suite of molecular and non-molecular (i.e., physiological method) methods you would use to study the plant. Be sure to describe what information each technique would reveal and to what extent, and the tradeoffs and limitations of the techniques