Maintenance items for the turbidimeters and pH instrumentation include the following. Scheduled periodic maintenance requirements of the turbidimeters are minimal and include calibration and cleaning of the photocell, bubble trap, and body. Check and clean the bubble trap and turbidimeter body, if visual inspection shows that it is necessary. It is very important to maintain the cleanliness of the interior and exterior of the turbidimeter body, head assembly, the integral bubble trap, and the surrounding area, to ensure accurate turbidity measurements.
- Daily: Check for proper operation. Instrumentation calibration as required.
- Weekly: General housekeeping, visual inspection and daily items. General housekeeping. Check the sampling tubing for accumulation of debris/sediment. If sediment is present in tubing, check the instrumentation. Clean as necessary. Clean the pH sensors and inspect for damage.
- Monthly: Clean the vial and vial compartment. Replace the vial as necessary. Inspect any dirt accumulation.
- Quarterly: Calibrate the raw water turbidimeters per manufacturer’s recommendations using an EPA approved primary standard. Clean the raw water instrumentation as necessary.
- Annually: Replace turbidimeter tubing as necessary.
Maintenance items for the blowers include the following:
- Daily: Check for proper operation and alignment.
- Weekly: General housekeeping. Check suction and clean filter.
- Quarterly: Exercise isolation valves. Check and replace the seal on the output shaft of the blower element. Check operation of lubrication disks.
- Annually: Change oil. Check bearings. Thoroughly inspect drive motors. Check belt tension. Inspect wear parts and replace if necessary.
Maintenance items for the Contact Adsorption Clarifiers include the following.
- Daily: Check for proper operation of all equipment.
- Weekly: General housekeeping. Check for proper operation of all equipment. Backwash CAC units if they haven’t been backwashed in the last seven days. Observe the air scour and water flush for proper distribution of air/water. Check the function of automatic and positioning valves. Inspect the media, wash any accumulation of sludge with a low pressure hose. Inspect retainer screen.
- Monthly: Observe and check the headloss switch adjustment. The switch shall start a flush cycle in AUTO when the gauge reads 6 feet of headloss. Exercise valves. Check retainer screen bolts and tighten if necessary.
- Annually: Drain each CAC unit. Inspect bottom for sediment and remove if observed. Observe the interior and exterior tank coating for damage. Re-coat as necessary. Inspect media and replace as necessary.
Hardcopies of manufacturer’s O&M manuals are on file at the WTP and should be consulted for a complete list of required preventive maintenance items, as well as for major maintenance items or in the event of equipment failure.