55A - SAN LORENZO SEWER LIFT STATION

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Giroux & Assoses 1820 East Garry St.,62 Ph: 949.387.5477 Environmental Consultants Santa Ana, CA 92705 Fax: 949.387.5477 r 1AV January 12, 2012 Mr. Robert P. Silverstein Attorney at Law 215 N. Marengo Ave., 3rd Floor Pasadena, CA 91101 -1504 Subject: San Lorenzo Sewer Lift Station Dear Mr. Silverstein: At your request, we have reviewed the most recent air quality impact analysis for the above project. The previous analyses identified an odor impact distance of approximately 75 feet from the source to the receptor without substantiation as to the basis for the selection of such an impact distance. Our review concluded that if one accepts this impact distance, the nearest motel rooms at the California Lodge would be located within this impact distance. With apparent slight rearrangement of the site, the RDEIR now concludes that there is 75 feet and 6 inches of separation between the center of the exhaust fan and the nearest motel window. The conclusion is unsupportable or inaccurate for a number of reasons. There is no basis in the technical literature for lift station siting that supports 75 feet as an absolute zone of impact. Lift Station Design standards for public works agencies identify the importance of considering the relationship between a lift station and land use, but an extensive search of standards throughout the United States shows no recommendation of 75 feet as an absolute set -back distance. For example, a typical standard states as follows: Every effort shall be made in site selection to reduce potential for odor pollution. Wind direction, duration and intensity are all important considerations that must be evaluated. (City of Reno Wastewater Lift Station Design Standards, July, 2007) The RDEIR presents no supportable information that "wind direction, duration and intensity have been considered in the adoption of the 75 -foot "approximate" impact distance. To the contrary, authoritative literature contradicts the unsupported conclusion of odor impact distance in the RDEIR. Attached hereto is a scan of the cover sheet and page 1654 of an authoritative engineering manual, Wastewater Engineering, Treatment And Reuse, Metcalf & Eddy Inc., McGraw Hill, Fourth Edition, 2003. That treatise states that "Depending on the local meteorological conditions, it has been observed that odors may be measured at undiluted concentrations at great distances from the point of generation.... In some cases, odors have been detected at distances of up to 25 km from their source. This transport phenomenon has been termed the puff movement of odors (Tchobanoglous and Schroeder, 1985)." 55A -228