Specifications include, but are not limited to: 1. First phase (Third week of March 2019 – immediately following award of contract) – remove all fiberglass covers from all eight (8) existing units, and remove one (1) long shaft\rotor assembly (the set closest to the driveway). Set the first three (3) replacement mechanical aerator units. Estimated duration for this phase is four (4) working days. 2. Second phase (estimated second week of April 2019) – remove short shaft\rotor assembly and set the remaining two (2) mechanical aeration units. Note that one (1) of these units is a floating unit (see product sketch). Estimated duration for this phase is one (1) working day. 3. Third phase (estimated second week of May 2019) – remove second long shaft\rotor assembly and set the next three (3) replacement mechanical aerator units. Estimated duration for this phase is two (2) working days.