SNC Lavalin Constructors
After providing acoustical consulting, mitigation design and quality assurance of the installation for Phase I of the Astoria Power Plant, INNOVA was contracted by SNC Lavalin Constructors to develop noise control for the Phase II 500 MW expansion. The Astoria Energy project is located next to the Steinway piano factory's tuning room, a boat club and nearby a children's playground so noise control was extremely important.
SCOPE OF WORK
INNOVA designed, supplied and installed all noise control and provided a site-wide compliance guarantee. Acoustic mitigation and other scope included:
- Gas Turbine Hall
- GIS Building
- FGD Building
- HRSG Wind Wall
- ACC Unit
- Pipe Racks
New York City has regulations with different noise criteria. As part of the Article X permitting application, the plant is required to be evaluated against the following regulations:
- New York City Zoning Resolution, Section 42-21 (1999): 60dBA at the property line
- New York State Department of Public Service (NYDPS) Composite Noise Rating: Rating of C
- New York City Environmental Quality Review (CEQR): 65dBA day, 3 dBA over ambient at night limit
- New York City Noise Control Code: Max. allowable sound pressure levels within octave bands
The combined noise sources for Phases I & II of the Astoria power plant were:
- Four (4) GE 7FA gas turbine generator units – 116 dBA
- HRSGs – 106 dBA
- Two (2) Alstom steam turbine generator units – 117 dBA
- Two (2) 24-cell Air Cooled Condenser (ACC) unit – 102 dBA
- Two (2) Fuel gas compressors – 127 dBA
- Gas Piping – 83.4 dBA
Phase II mirrored Phase I's 40,000 sq. ft. acoustical turbine hall, 110' high wind wall and fuel gas compressor enclosure. In Phase II, INNOVA also supplied a GIS enclosure and custom-designed baffles for the ACC unit along with the pipe rack steel. INNOVA used two of its proprietary acoustical assemblies for the walls and roof of the turbine, GIS and FGC enclosures and installed custom-designed ventilation silencers for the buildings. INNOVA provided an overall noise guarantee for the entire 1100MW site, including the existing Phase I.
INNOVA also installed:
- Structural steel
- Electrical, doors
- Partitions and ceilings
- Two (2) overhead bridge cranes
UNIQUE PROJECT HURDLES
In addition to the stringent noise regulations, the project also had many logistical challenges. The small site, surrounded on three sides by water, also was without a laydown area, requiring all material deliveries to be “just in time” and resulting in the wind wall being built from the “inside out”. INNOVA's organization and utilization of off-site marshaling facilities to ensure precise material management were key components to the success of construction. INNOVA also had to ensure that relations with the various unions were seamless. Phase I of the plant was up and running as Phase II was being constructed, so INNOVA had to work efficiently to minimize downtime of the existing plant. Coordination and communication were key during this project.
INNOVA created a mitigation plan prior to the commencement of Phase I construction that guaranteed both Phases I & II could be constructed without exceeding the noise regulations. Although Phase II doubled the project's size and power, the noise levels did not increase due to INNOVA's carefully designed mitigation plan. The post construction noise level at the nearest sensitive receiver – a children's playground – is 47 dBA. INNOVA completed the Phase ll project in the second quarter of 2011 after logging over 60,000 safe man-hours. All critical milestones were met or exceeded with acceleration of the schedule. By choosing INNOVA, SNC Lavalin achieved guaranteed compliance with the multiple noise ordinances of New York City.