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ARDEN HILLS CITY COUNCIL WORK SESSION—NOVEMBER 28, 2011 4 law does not come into play. Another issue is that the noise analysis was driven by the fact that the access is being changed on US 10 and such an analysis is focused on the footprint of the project which involves only Lakeshore Place and impacts only five or six homes. The analysis stops before the vacant lots and does not include properties south of those lots. He stated the law is clear regarding vacant lots under the old law; there has to be buildings on the lots to be included in the analysis. Under the new law, there has to at least be a building permit issued. He further stated that this area was looked at in March 2008 when SEH did a noise analysis. At that time there were two noise receptors on Lakeshore Place which showed that the AM and PM noise was approximately 70 decibels. After the project was built, they estimate the increase in noise was between 1.5 and 2.8 decibels. According to noise experts, in order for an increase in noise to be detectable, that increase would have to be at least 3.0 decibels. Also in 2008, a cost effective analysis at that time for a 20-foot high wall, 870 feet long and a 10-foot high wall was done. The 20-foot wall was determined to be $5,839 per decibel and the 10-foot wall was $10,875 per decibel. Public Works Director Maurer explained that in 2010 Ramsey County hired Bonestroo to do the Environmental Assessment for the US 10/Highway 96 grade separation. Bonestroo hired Jacobs Engineering to do the noise analysis. Jacobs put in five model receptacles on Lakeshore Place. The decibels at these locations ranged from 64.6 to 67.5 and the anticipated increase after construction was 2.5 to 4.6 decibels. They then prepared an analysis of a 900-foot wall in the same area with a varying height of 10 feet, 15 feet, and 20 feet. The 20-foot high wall was over $5,000 a decibel, the 15-foot wall came out at$4,700 per decibel, and the 10-foot wall was $7,600 per decibel. In order to make the 15-foot wall cost effective, the decibel benefit would have to increase from 43 to 62 without increasing the wall length. Public Works Director Maurer then stated that the County does not have any money for another noise analysis and MnDOT is not interested in pursuing it. He added that Joe Lux, Ramsey County Transportation Manager, went back to the FHWA regional representative and confirmed that the County could not build a noise wall that is not cost effective or outside the footprint of the proj ect. Councilmember Holden asked if the City hired a noise consultant for the Briarknoll neighborhood project. Public Works Director Maurer responded that he does not believe the City hired a consultant; but Chris Chromy reviewed the information gathering for the City. He added that Chris has looked at all the numbers in detail. He explained that he, Chris Chromy and Joe Lux have carefully reviewed the noise wall issue several times over the past months and it just cannot be made to meet the cost-effective criteria. Councilmember Tamble stated that the point he has tried to make is that the City have a final documentation to show the residents that the Council has done all that it can on behalf of the residents' request for a noise wall. He suggested the City focus on what they can get; the increased height on the existing wall and additional plantings.