To Whom It May Concern,
Subject: I-70 Expansion in Colorado. PEIS Comments
5 Feb, 2005
General Encompassing Comments
It now seems clear that something has gone dreadfully wrong with the I-70 CDOT PEIS. I reached this conclusion after attending the fifth ---and my fourth ---CDOT PEIS Public Hearing on the I-70 Expansion.
The purpose of an EIS is to present to the public ---and have the public accept -----a well documented study of the impact on the environment of the proposed project. The CDOT I-70 PEIS is seemingly a well documented and broadly extensive EIS study, but the I-70 public ---after closely studying the PEIS ---are not close to accepting it. The public are claiming they are finding major flaws in this most costly and far reaching PEIS for the I-70 expansion project.
The particular environmental component of concern that I have experience with -----transportation noise ---- is clearly and highly flawed, (see noise comment attachment). After attending four of the public hearings I am now convinced that other significant environmental study components of the I-70 PEIS are most likely just as flawed as the noise component. Among these I believe are air quality, water quality, economic losses, and possibly many more of the remaining environmental components.
In a few words, the CDOT PEIS simply does not adequately describe the full environmental impact, but rather it nibbles at the edges of the true impact of the I-70 Expansion Project. On a scale of 1 to 10 this writer would give it no more than a 2 to 3 !
The expansion of the I-70 corridors through Colorado is not a simple task or simple project. It is immense and it will be immensely challenging from an environmental viewpoint. But, having public hearings on a highly flawed PEIS is not the way to win public support for this project.
If this PEIS is to accomplish anything positive CDOT should immediately take action to stop the adverse snowballing effect the Public Hearing Meetings are having.
Unfortunately, I see no quick way or quick fix to accomplish this goal.
I-70 Expansion Draft PEIS
Comments on Noise Section 3.12 and Appendix A
These comments are listed in descending order of importance as viewed by the writer.
1) The 66 dBA Leq level designated by the FHWTA ---and agreed to by CDOT ---as the criteria (or “Standard” as it is called in Appendix A) for mitigation is an immediate indication that noise and noise mitigation are not being recognized as a serious environmental component of this study. 66 dBA Leq is equivalent to the annoyance of four persons all talking over each other continuously for each hour the Leq remains at 66 dBA !
This PEIS correctly shows normal conversation at three feet to be equivalent to 60 dBA, and this PEIS correctly states that a doubling of sound pressure produces a 3 dBA increase. A four fold increase of sound pressure from 4 speakers at 3 feet will therefore raise the dBA value 6 dBA from 60 to 66 dBA.
Citizen response to annoyance levels at 66 dBA Leq will range around 20 % highly annoyed, 45 % annoyed and 65 % little annoyed, as published by Dr. Hank Miedema of The Netherlands.
Accordingly, 66 dBA Leq is much too high a noise level for a “Standard” for highway noise annoyance boundaries.
A more appropriate standard would be 55 dBA and would represent a much better compromise between annoyance levels and mitigation costs.
2) This PEIS again shows it relegates noise to a less than important environmental element when it chooses to report all noise exposure levels in units of dBAs rather than the more citizen-friendly units of % annoyed.
The average citizen along I-70 has no concept of the dose-response curve associated with transportation noise. He must be spoken to in units of % highly annoyed, % annoyed, and % little annoyed.
Until road-traffic annoyance dose-response relationships are introduced the noise study in this PEIS is essentially in a foreign language.
3) Transportation noise exposure levels and noise annoyance levels cannot be accurately described without relationship to the community noise levels when all transportation noise is absent. It is the “difference” between this community noise exposure level compared with the peak hour levels of transportation noise that drives the dose-response relationships. When this difference reaches 10 dBA ---- a doubling of loudness to the average ear ----the transportation noise is egregious and should labeled so.
4) The green and red noise contour lines shown on Figs. 3.12-7 etc., are another demonstration of a PEIS which is deficient in communicating true noise annoyance levels to the affected parties. A single 66 dBA contour line does not ---and cannot ---- show the noise exposure level as a gradient that diminishes as the distance from the noise source increases.
The true noise exposure contour detail can only be shown with a series of equally co-charted exposure lines set at decreasing dBA levels, for instance 66 dBA, 64, 62, 60, 58, 56, 54, etc. And, means should also be provided to equate these dBA contour lines to contour lines of annoyance. These contour gradient charts should extend out to the residential area outer limits in the community affected so that every residence can be associated with a specific noise exposure annoyance level with a high level of certainty.
5) The author of the PEIS noise study cites an incorrect relationship between noise exposure levels and distance from highway transportation noise. The PEIS sates that noise exposure levels will diminish at the rate of 4.5 dBA for every doubling of the distance from the highway. The laws of physics and mathematics show this relationship to be only 3 dBA per doubling, not the steeper 4.5 dBA per doubling claimed in this PEIS.
6) In all of the above comments the net result found is one of diminishing the predicted impact of the noise exposure in this PEIS below what it actually will be. This finding is not just coincidence to this writer, but a clear indication that the average reader is being led to believe that another noise study will once again be shown to have produced another FONSI ---finding of no significant inpact ---when just the opposite is true.
Glen H. Schulze
Noise Specialist
Littleton, CO
W:303 973 8147
H:303 979 7890
G_Schulze@msn.com
