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BACKGROUND Lift Stations 7 and 8 were built under a common construction contract in 1978. Together, they serve five sewer collection sub -basins within the southern portion of the City, conveying sewage to DSRSD's regional wastewater treatment plant. Other than minor operations and maintenance work, no significant capital improvements have occurred at either station since they went into service over 42 years ago. Over time, sulfides generated from wastewater flowing through the stations cause corrosion' to exposed life -safety systems, including the ventilation, lighting, and other related systems. In order to ensure a safe work environment for the City's Utilities Division staff, and to bring the stations into compliance with current code requirements, replacement of the ventilation systems (fans and ducting), new interior lighting, and new hazardous gas monitoring systems were needed. In May 2020, the City hired TJCAA under an on-call design professional services agreement for $72,587 to develop the project plans and specifications required to publicly bid the project. The plans and specifications were completed in January 2020 and bids were open in February 2021. On March 2, 2021, City Council awarded a construction contract to WestCal Design and Build, Inc, in the amount of $1,020,000 authorized a contingency in the amount of $153,000, and awarded a professional services agreement to TJCAA for construction support services for $53,500. DISCUSSION The Lift Station 7 and Lift Station 8 Ventilation and Lighting Improvements Project completed the necessary repairs to the ventilation and lighting systems at the two stations that had reached the end of their useful life. The project included the removal and replacement of all the existing ventilation equipment and upgrading the equipment to current standards, including new ducting, fans and control panels. The lighting systems within the station wet wells were replaced, and various other non-functioning light fixtures were replaced throughout the remainder of both stations. The air monitoring systems that screen for hazardous gases and oxygen levels within the stations that are required to allow personnel to safely access the stations were replaced. Finally, both lift stations control systems were connected to the City's existing SCADA system to allow for remote monitoring. Five change orders were issued for the project totaling $47,692.11. The first change order was a no -cost change order incorporating building plan review comments. The second change order was for additional conduit work for the air monitoring system to accommodate larger wire sizing for the new system at both locations. The third change order covered the cost to seal the existing louvers that were not adjustable at both locations. The fourth and sixth change orders were to address modifications to the registers and fans required to meet the airflow requirements due to changes from existing floor penetrations. The fifth change order relocated the electrical supply to two water booster pumps that conflicted with the new supply duct floor penetration at Lift Station 7. Consultant Services The project designer, TJCAA, provided construction support services which included reviewing shop drawings, responding to requests for information, and providing inspections. Page 2 of 3