2-Attachment B Scope of Work 1.docx

Attachment B Scope of Work

NC27-122

Vacuum Air Lift VAL Upgrade Springville Fish Hatchery

1. Introduction This scope of work is to upgrade the Vacuum Air Lift (VAL) at Springville Fish Hatchery (1115 North Main St, Springville, UT 84663). The VAL was installed in 2020 to remove excess CO2 from the fish hatchery water supply. The intent is to upgrade the VAL to function more reliably. This includes, among other things, upgrading the existing sensors and water separation systems. Coordination with DWR staff will be necessary to protect fish health and water flows. This project should be completed by January 2027.

1.1 Background

The Vacuum Air Lift was installed in 2020 to address excess gases, primarily CO2 in the fish hatchery supply water. Excess gases are detrimental to the health of the fish and long-term exposure can be fatal. Generally, the VAL has functioned well in reducing excess gases. Over the past year we’ve encountered issues with a few of the components. The current issues stem from the unreliability of the level sensor at the top of the VAL. It is a custom-built sensor that has been unreliable and difficult to replace due to lengthy lead times (3+ months). It has been replaced four times in six years. Sensor malfunctions have increased in frequency causing the system to shut down every few days. Additional capacity for water separation is also necessary to allow the system to purge greater volumes of water.

Searen, the engineering firm that installed the VAL, has proposed several upgrades that can be done to improve the long-term viability of the system. This includes replacing the level sensor with pressure-based sensors, increasing the size of the water separator, and upgrading the air diffusers with more efficient models. These upgrades will be discussed in greater detail below.

1.2 Scope of Work

The project will require the following:

Pressure-based water level management

· Replace the existing level sensor with pressure-based sensors (4-20 mA), including mounting hardware and electrical connections.

· PCL scaling for pressure-based measuring range.

· Signal filtering, under-range/over range diagnostic, and HMI indication of raw signal, measured level, and sensor status.

Diffuser Upgrade

· New diffuser assembly (x4) and associated air-distribution components.

· Review and adjustment of diffuser layout, supports, and connections.

Water Separator Remodel

· Replace existing liquid separator between the VAL and the vacuum system.

· Improve liquid separation, drainage and protection against water carryover.

· Verification during startup, normal operation, high-water conditions, shutdown, drainage, and air purge.

PLC and HMI Update

· Programming changes required for new sensors and updated equipment.

· Review of pump alternation, valves, alarms, startup, operation, shutdown, drainage, and purge sequences.

· Updated HMI diagnostics, extended screen backlight duration, and backup of existing and revised programs.

Field Services and Commissioning

· Level sensor calibration and PLC/HMI commissioning

· Operational testing of diffusers, separators, valves, pumps, and alarms.

· Final adjustment of operating parameters and operator maintenance review.

· Coordinate work with hatchery personnel to avoid operational impact.

1.3 Requirements

Candidates for this project must understand the principles behind the vacuum air lift system, its functions, and importance to fish hatchery operations. Candidates should also have experience in installing sensors and pertinent automation systems, including PLC/HMI components. Adherence to hatchery biosecurity requirements is also required while at the jobsite.

2. Compliance The awarded vendor will be responsible for purchasing and installing all the necessary components to upgrade the VAL. Total gas pressure will be measured by hatchery staff to verify that the upgraded VAL continues to reduce CO2 and nitrogen gas in the supply water.

3. Project Deliverables The project manager will ensure that the new components are installed correctly and are in good working order. They will also work with hatchery staff to verify that dissolved gasses are in the desired range. Updated blueprints will be provided. Hatchery staff will be adequately trained on the updated systems, including day-to-day operations and troubleshooting procedures.

4. Project Timeline The project should be completed by the end of January 2027.