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BACKGROUND The fire training tower, located at the Operations Services Center, was designed in 1987 by architect Jack Bras of Pleasanton and structural engineer Oliver Baer of Hayward and was constructed in 1987-1988. The structure is seven stories tall, including a partially sunken basement, and is irregularly shaped with overall dimensions of 53 feet by 56 feet by 70 feet from the basement floor to the top of the structure, consisting primarily of reinforced concrete. The structure is unoccupied and is used exclusively for training purposes. One of the primary purposes of the structure is to train personnel during live-fire exercises. These exercises involve burning bins of hay inside one of two "burn rooms" within the structure (one room in the basement and the other on the second floor), creating a very hot and smoky environment. The temperature within the room is allowed to reach up to 800°F before the fire is extinguished. While there are insulating panels installed on the walls and ceiling of the burn rooms intended to help protect the concrete, the concrete still gets very hot. These temperatures do not last long, but the fires are repeated several times during an exercise. Up until 2017, exercises were held an average of six times per year. In 2017, the live-fire exercises were placed on hold as damage was observed at various locations within the structure and a structural assessment was needed. In 2018 and 2019, Finn Design Group, Inc. (Finn) and BSK Associates (BSK) conducted visual observations and non-destructive testing of the fire training tower. This was the first structural assessment performed since the original construction of the tower. The inspections and testing identified that the damage occurred to the structure as a result of both its use as a fire training center (high-temperature subjection) and from general exposure to the elements. It was recommended the following repairs be completed to resume the full use of the building and extend its useful life: • Existing spalls (floors, ceilings, and walls) should be repaired with a specially applied mortar topping and significant cracks in the concrete should be epoxy injected. Any loose concrete should be removed prior to patching with new material. Any exposed rebar should be treated with a corrosion remover and inhibitor prior to resurfacing. • A concrete sealant should be applied to all surfaces exposed to the elements. • After the repair work is done, photographs of the floors, ceilings, and walls, should be taken to document the physical state of the building. (The photographs may prove very useful in the future, if and when future damage occurs.) • The insulation board in the burn rooms should be replaced. In February 2021, the City hired BSK and Finn (a sub-consultant with BSK) under an on-call design professional services agreement for $31,456 to develop project plans and specifications to publicly bid the project. In June 2021, the fire training tower was closed. A detailed inspection and mark-outs identifying the needed repairs were completed. The fire tower remained closed to preserve the markings that identified the areas of repair. Page 2 of 4