Multiple Analysis and Measurement Methods to Confirm the Absence of Noise Impacts from a Power Plant

This paper describes how the licensing of a power plant project presents the analysts with a series of challenges. This project involved the replacement of two power units (Units 1 and 2) with three combined-cycle units (Units 5, 6 and 7) at an existing power plant. The plant is adjacent to the coastline, which proved to be the dominant noise source at the nearest noise-sensitive receptors. In addition to the noise from surf, other major ambient noise sources included road traffic and a nearby international airport. The general layout of the site and surroundings and the major project features are shown and the initial analysis, which was straightforward in nature, concluded that noise levels with the project would be within the relevant regulations and standards. The project would replace old, inefficient equipment with new, more powerful, efficient and quieter equipment (as abated). Additionally, the new equipment was sited far enough from the residences (approximately 670 meters) and would be acoustically shielded by the remaining, still operational units (Units 3 and 4). Subsequently however, several of the nearest residents (located south of the plant) raised a question: Could the removal, as part of the project, of two large fuel oil tanks from the southern end of the plant property cause an increase in the noise levels received at their homes from the remaining Units 3 and 4? The fuel oil tanks (each of which is 67 meters in diameter and 15 meters in height) block much or all of the direct view to the power units from several of the nearest residences. By removing the tanks, residents would have a less obstructed view of the power units, although intervening terrain and structures would still shield varying portions of the facility, depending upon the observation point. Based upon initial noise measurements, analysis and critical listening conducted during the site visits, the analysts did not believe that removal of the fuel oil tanks would in fact result in higher noise levels, because of the large distances between the plant and the residences, but more importantly, by relatively high ambient levels. The difficulty, however, was in substantiating this quantitatively - in effect, trying to do the impossible and “prove a negative”.

Language

  • English

Media Info

  • Media Type: Audiotape
  • Features: Figures; References;
  • Pagination: pp 932-941
  • Monograph Title: Noise-Con 04. The 2004 National Conference on Noise Control Engineering

Subject/Index Terms

Filing Info

  • Accession Number: 01054376
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jul 26 2007 2:16PM