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Section 2 r i0tt ( i, i i r,wn, i , i �i t , - ,i, - o -i ; : r,, , , (DOT/FRA/ORD-12/15, September, 2012) provides the basic guidance and procedures for the assessment of potential noise and vibration impacts from proposed high-speed ground transportation projects. This manual is intended for projects with train speeds of 90 to 250 mph. The manual is similar to the FTA Transit Noise and Vibration Impact Assessment manual (which is intended for projects with train speeds up to 90 mph). An important characteristic of the noise from high-speed trains that is absent from the DEIS noise analysis is analysis of the onset rate of the sound signature. Onset rate is the average rate of change of increasing sound pressure level in decibels per second during a single noise event. The rapid approach of a high-speed train is accompanied by a sudden increase in noise for a receiver near the tracks. Based on the absence of discussion of onset rate and use of the FTA manual figure showing typical A -weighted maximum sound levels instead of the FRA manual showing typical A -weighted levels of high-speed train sources, indicates that the noise analysis relies more on the FTA manual than the more pertinent FRA high-speed train noise manual. The DEIS lacks calculation details and quantitative support for its impact assessment as required by the Federal Railroad Administration manual. In general, the impact assessments are lacking calculation details and quantitative support. The Proposed Project is well beyond the initial planning stages. Therefore, these calculations and support documentation should be required as part of the DEIS analysis. The DEIS fails to include an evaluation of noise and vibration impacts on subterranean archaeological sites and vertical historical sites along the N -S Corridor. The FRA manual references Section 106 and states with regard to historic and archaeological sites, "Special protection provided by law. Section 4(f) of the DOT Act and Section 106 of the National Historic Preservation Act come into play frequently during the environmental review of transit projects. Section 4(f) protects historic sites and publicly -owned parks, recreation areas and wildlife refuges. Section 106 protects historic and archaeological resources." The DEIS does not include a complete list of the subterranean archaeological sites and vertical historical sites along the N -S Corridor. It therefore does not evaluate the Proposed Project's noise and vibration impacts on the subterranean archaeological sites and vertical historical sites along the N -S Corridor. Moreover, AAF made no attempt to collect representative noise data at a representative sampling of intersections along the corridor, as is required by Section 106 of the NHPA. Specifically, CDM Smith noted the following deficiencies: The DEIS relied on an inaccurate methodology for determining existing noise levels. The FRA manual recommends that noise be considered in terms of divergence, absorption/diffusion and/or shielding at a distance of 50 feet from the source. Existing noise levels at 50 feet were not monitored in the field, but rather estimated based on the FTA Guidance Manual based on population density or proximity to an interstate highway, airport, or an existing rail line. No figures are presented to show the existing ambient noise levels in the Project Study Area derived from these different estimated noise levels. Existing ambient noise levels would be helpful in comparing existing and future build impacts at sensitive land uses and historic properties. Measurements of existing ambient noise levels, especially at sensitive land uses and historic properties, should have been used as the combination of various transportation and urban noise sources can be complex. See Appendix B of the FRA manual which discusses options for determination of existing noise levels ranging from full measurement (more accurate) to tabular lookup (less accurate). 2-4 3 0 ► 3 Smith