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Paul Martin, representing the applicant, said their sound consultant, Jeffrey Pack, was present to address questions. He thanked Mr. Dolan for his presentation which was thorough and said he was available to take questions. Mayor Hosterman asked where the measurement of the decibels took place in relation to the setback. Mr. Martin said Mr. Pack could address questions relating to the sound study. In addressing a previous question, they are amenable to bond for the cost of installing a tot lot, wait until 11 of the 13 units are occupied, and then hold a vote of the HOA. Jeff Pack, Edward L. Pack Associates, said the calculations are accurate. He had to measure 75 feet from the tracks because of shrubbery restrictions. The noise levels in the table and throughout the report are then calculated for the building setbacks, taking this into account. He calculated for every lot on the site under best and worst case conditions along Stanley and along the railroad. Vice Mayor Cook-Kallio said she has a two-story building close to the railroad tracks and asked whether duration of the whistle was measured. Mr. Pack said there is a wide range of data. He said L-Max which is what is in the General Plan for railroad noise, is the measurement of the loudest part of noise if shorter than one second. A train horn can last anywhere from a short beep to a longer whistle depending on what is seen on the track, and it also depends on the engineer. Councilmember Thorne questioned under what conditions the 112 dBA rating was achieved. Mr. Pack said he was out on the site for the entire 3-day period. Out of every one minute interval, average data is provided; the highest one second level data for each one minute period. When he sees a maximum of 112 dBA, it is a loud event. Councilmember Thorne agreed and said 115 dBA is the maximum industrial noise for an intermittent noise. Mr. Pack agreed and said it is a very loud event, but very short also, at one second. Councilmember Sullivan questioned noise levels in the rear yards of these lots. Mr. Pack said the outdoor noise policies of the General Plan are for 24-hour averages. The City's goal is 70 decibels when the noise sources are railroads and 60 decibels for a non-railroad source, such as traffic. They use the 70 dBA level for outdoor areas, and this is why the 8 foot sound wall is required. Councilmember Sullivan questioned what the exterior peak noise is. Mr. Pack said peak noise also has specific definitions for acoustics as done maximum. The outdoor maximum sound levels are either at the property boundary, at 57 feet, or for a wider area. They could look at what he measured from 75 feet compared to what is calculated for the setback at 57 feet, see the difference, and identify how things change over that space. In getting further away, they diminish. He said this data is not addressed in the General Plan as a planning policy, but maximum sounds represent the train horns, and measured sound levels are the outdoor maximum sound levels that were measured at 75 feet, which is 89 to 112 dBA. Councilmember Sullivan said the actual outdoor noise levels at the lots were not evaluated like they were for the indoor noise levels. Mr. Pack said they were; the next column in the report indicates "sound levels at the setback" which are at 57 feet. They went up from 112 to 115 for one very worst case scenario. Therefore, it is anywhere from 92 to 115 dBA, except for lot 1, which was most likely the event of a motorcycle or emergency vehicle along Stanley Boulevard, which was not counted. He also noted that pile driving and train horns are very different kinds of noise sources. Pile drivers at a close distance get close to 120 to 125 dBA's, but it is an impulse sound with a rapid onset and decay or bang, and much more startling than a train noise that has slower onset and more of a decay. The awakening threshold between the two would also be different. Councilmember Sullivan said the study also shows there are significant vibration problems caused by the train, which requires some mitigation on foundations. Mr. Pack agreed. City Council Minutes Page 9 of 16 September 6, 2011