(A) Metra will follow FTA requirements and the policy set forth below. To the extent they are feasible and prudent, mitigation measures may be applied at the source, along the path or at the receiving building. However, the most cost effective measures are generally applied at the source.
(B) Metra will use the following cost-benefit criterion for new Metra lines to determine the reasonableness of implementing vibration mitigation.
(1) The minimum length of track mitigated must be determined from calculations based on the FTA detailed analysis method. In no case will the length be less than one-half of a commuter train length.
(2) The vibration mitigation treatment must provide at least three VdB reduction for every impacted dwelling to be considered effective.
(3) Metra will apply the following formula to determine if the mitigation is cost effective: length multiplied by cost/feet divided by VdB reduction divided by number of buildings protected. If this dollar amount exceeds $15,000, the treatment is not considered to be cost effective.
(C) The criterion is designed to ensure that vibration mitigation is installed in areas where receivers would benefit significantly, but not in areas where they would do little or no good. A balance is struck between the minimum treatment required for one dwelling and the economy of providing for multiple residences.
(Ord. MET 02-25, passed 8-16-2002)