HWRP Flare System Replacement and Battery B Digester Demolition (W.O. SZH12229 and SZH12318 / CIP Nos. 2520 and 2528)

The project involves the demolition of six decommissioned digester tanks at the Hyperion Water Reclamation Plant in Los Angeles and the installation of a new ultra-low emission flaring system to comply with South Coast Air Quality Management District regulations, particularly Rule 1118.1, which limits nitrogen oxide emissions to less than 0.025 pounds per million Btu. The new flare system will have a capacity of 11 million standard cubic feet per day and include six ultra-low NOx flares capable of handling both high- and low-pressure digester gas. Additional infrastructure encompasses moisture removal systems, digester gas blowers, gas cooling heat exchangers, a hydrogen sulfide removal system, above-grade high- and low-pressure gas piping, a dedicated building for blowers and controls, a standby generator in an enclosed structure, concrete foundations, and designated space for future ammonia removal equipment. The demolition component involves removing all above- and below-ground structures and equipment from the six Battery B digesters, excavating soil to an elevation of 24 feet (20 feet below grade), and disposing of approximately 8,308 cubic yards of concrete and 153 cubic yards of piping and equipment. Work is conducted under Capital Improvement Program numbers 2520 and 2528, with performance driven by milestones mandated by the SCAQMD as part of an abatement order, requiring acceleration to mitigate potential delays. All work must adhere to the City of Los Angeles Municipal Code, Bureau of Engineering Standard Plans, the 2012 and 2021 editions of the Standard Specifications for Public Works Construction (including amendments), and the Work Area Traffic Control Handbook. Additional requirements include strict compliance with fire safety protocols in accordance with the Los Angeles Fire Code, Chapter 33, including clear access paths, prohibition of smoking, availability of fire extinguishers, cooling equipment before refueling, and maintaining fire department contact information. Cultural resource protection mandates immediate cessation of excavation upon discovery of archaeological or paleontological materials, with work halted until authorized by the Engineer. Noise and vibration must conform to the more stringent of Los Angeles or El Segundo ordinances, with construction limited to weekdays from 7 a.m. to 9 p.m. and Saturdays from 8 a.m. to 6 p.m., while high-noise activities are restricted to 7 a.m. to 6 p.m. Construction site notices must be posted, adjacent property owners notified in writing, truck traffic rer