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condition of approval addresses this item. • Install a 6-ft. tall acoustically effective barrier along the rear and street side yards of Lots 1 and 14. The applicant is proposing to install a 6-ft. tall wood sound fence at these locations. • Install doors and windows with minimum Sound 'transmission Class (STC) ratings of 28 to 46 depending on lot, floor level, and occupancy of the room/area (see Table I of the noise study for specific requirernelts). • The homes would need to be provided with forced air mechanical ventilation (i.e., air conditioning) so that windows and doors may be closed at the discretion of the occupants to control noise. Staff notes that the above mitigations address train engine/wheel noise and exclude full mitigation for train whistles as these short, very loud events would require mitigation measures that would be infeasible and/or unacceptable from a design and neighborhood impact standpoint: install a 29-ft. tall soundwall along the project boundary adjacent to the railroad and flanking the sides of the project for 93 ft. The flanking wall heights would then step down in increments from 25 ft. to 15 ft. all the way to the Stanley Boulevard right-of-way. The General Plan indicates that the City Council will evaluate the requirement to achieve the General Plan noise standards on a case-by-case bass in the Downtown and, in this case, staff believes that there isn't a feasible mitigation for the train whistle noise. 'therefore, staff supports the mitigation measures as outlined in the noise study and a condition of approval requires that the applicant comply with the recommendations of the noise study. Noise Impacts on Adjacent Properties The development of residential ises on the property will generate added urban noise, such as traffic, landscape maintenance activities, etc. However, noise levels will not change substantially from that currently experienced in the area. Ambient noise levels could actually decrease for some of the adjacent properties due to the shielding of train and traffic noise by the proposed soundwalls, fencing, and buildings. Short-term construction noise would be generated during any new construction of this site. The City normally allows construction hours from 8:00 a.m. to 5:00 p.m., Monday through Friday, with Saturday construction allowed if there are no nearby residents that could be impacted by construction noise or activities. Since there are existing residences directly adjacent to the proposed project site, staff is not recommending that Saturday construction be allowed. Staff is recommending a condition that would allow the Director of Community Development to approve earlier construction "start times" or later "stop times" only for specific construction activities (e.g., concrete pouring) if it can be demonstrated to the satisfaction of the Director of Community Development that that the expanded construction hours are necessary (e.g., the concrete foundations need to be poured early due to weather conditions). Construction PUD-82 Page - 15 - September 15, 2010