Ninety Checkpoints and Nobody Remembers All of Them
You walk into a medium-capacity activated sludge plant with dual clarifiers, a belt press line, and a polyelectrolyte station. The process engineer who set up the maintenance schedule listed every inspection point on a laminated sheet that's been hanging next to the QE panel since 2015. Half the operators follow it. The other half do the rounds from muscle memory and skip whatever they can't see from the walkway.
This template exists because muscle memory doesn't generate audit trails. When the provincial environmental agency pulls your last quarter of inspection records and finds gaps in redox logging or missing sludge blanket heights, the fine isn't theoretical.
Eight Operator Slots and What They Tell You About Shift Coverage
The operator selection fields list eight names. That's not a contact directory — it's the entire field crew for a multi-site contract. When you cross-reference operator assignments against visit motives over sixty days, you find out who's handling the alarm callouts at 3 AM and who's only ever logged for routine visits. That imbalance burns people out, and burned-out operators stop cleaning the ossimetro probe.
Visit motive tracks four conditions: ordinary, regulatory body presence, suspended activity completion, and TLC alarm signals. The ratio of alarm-triggered visits to routine ones is the single best predictor of whether a plant needs capital investment or just better preventive scheduling.
The Denitrification-Oxidation Block Where Readings Actually Matter
The pre-denitrification and oxidation sections capture five values that drive the entire biological process: redox potential in millivolts, dissolved oxygen concentration, sludge volume at the Imhoff cone, MLSS concentration, and aerated recirculation calibration.
Redox potential in the anoxic zone is a free-text field. It has to be. You're recording -150 mV on a good day, -80 mV when the recirculation ratio is wrong, and +50 mV when the mixer failed overnight and the zone went fully aerobic. A five-star rating can't carry that information. The operator standing on the platform edge with a handheld probe and a headlamp during a November rainstorm needs to punch in one number and move on.
Dissolved oxygen in the aerobic section follows the same logic. The difference between 1.8 mg/L and 3.2 mg/L is the difference between efficient nitrification and wasting sixty percent of your blower energy on over-aeration. Logging this daily, across seasons, builds the dataset that lets you tune the PID controller on the insufflation network instead of running it on a fixed timer like it's 1997.
Dual Settlers, Dual Headaches
The template duplicates the entire sedimentatore section: sludge blanket height, foam presence, supernatant coverage, weir cleaning, return sludge concentration, and excess sludge extraction. Each settler gets its own independent rating chain.
This matters because clarifiers drift asymmetrically. One will develop a thicker surnatante layer, partial coverage creeping toward total, while the other runs clean — usually because the carroponte raschiatore on the first unit has a binding issue that nobody noticed because they only checked the second one. The peripheral-drive bridge crane fields (1000511, 1000513) track correct movement, absence of binding, and proper skimmer function. A vibration score that drops from 4 to 2 across three weeks is a gearbox telling you it needs grease before it needs a replacement.
Belt Press and Polyelectrolyte: The Final Bottleneck
The nastropressa section doesn't just log "machine on/off." It tracks coclea blockage separately for two screw conveyors, nozzle cleanliness, greasing schedule, operating hours, and sludge bin fill level on the same six-point scale as the bar screen big-bags. When the bin hits 3/4 and the hauler isn't scheduled until Thursday, you know by Tuesday morning — not by the smell on Wednesday afternoon.
The polyelectrolyte station is its own subsystem: powder silo level, dosing screw function, mains water pressure, water-to-polymer ratio, heater operation, final solution quality, level probe cleanliness, and dosing pump stator temperature. Polymer underdosing means floc doesn't form properly, the belt press cake comes out at 15% dry solids instead of 22%, and your disposal tonnage jumps. Overdosing burns polymer budget and fouls the dosing lines. The template captures both the pump seal condition (tenute) and the dosing centralization unit as separate ratings, because the failure modes are completely different and diagnosing one from the other requires the historical trace.
Three separate QE panels — general, polyelectrolyte command, and belt press command — each get their own visual absorption check. An anomalous current draw on the nastropressa panel with normal readings on the other two points straight at the belt tension motor or the cake-breaking roller bearings.