Noise Discussion

This discussion was led by Rickard Zwolak of Golder Associates.  Other Sempra folks and the audience participated as well.  Notable items I picked out of this discussion included:

• They took measurements at a number of different locations around the Eastalco property and in the area during the day and at night

• They are required to meet the state and the more stringent local noise standards. [This is not quite true.  Technically they only have to meet the state requirements as the State jurisdiction in this matter supersedes the local.]

• Their studies conclude that they will be within the stated guidelines - both state and local. [It's nice to know they will still be able to meet both requirements even though they only need to meet the state.]

• He noted that in many places they are not even require to meet noise standards. [I felt this was an unnecessary comment.  Maybe it was the way he phrased it, but to me this implied that they were going out of their way to meet what he felt were unnecessary requirements.]

• H mentioned that when the train goes by, we're probably hearing 78-80 db, and maybe even up to 100 if you're right by the tracks.

• [Specific numbers from the testimony of Kennard F. Kosky include the nearest residence with predicted total noise levels of 46.7 and 47.3 dBA for the daytime and nighttime, respectively and in front of St. Matthew’s Lutheran Church  of 49.0 and 49.5 dBA for daytime and nighttime, respectively.]

Summary is that their studies and models show that the increase in ambient noise levels will be insignificant.  In most cases below what the human ear can perceive [.3 db was the number mentioned when discussing the school]

Questions and Answers [These are not anywhere near verbatim, they are what I remember as being the essence of the questions..]

Question: Would you consider using quieter fans?
Answer: .We will look at the use of the quieter technology fans, but it will need to be weighed against the actual noise decrease that it is able to deliver outside of the Eastalco property.

Question: What about steam blows?
Answer: The only steam blow that occurs happens during the initial start-up and commissioning of the plant.  During normal starts/stops there is a steam bypass in effect. but the additional noise output from this process is minimal.

Question: What about adding berms around the facility covered with grasses and trees?
Answer: A couple of points here:

• First, the berms would have to be placed on Eastalco property.  There is not room in the footprint of the Catoctin plant for them.

• Second, the berms really only have an effect for locations near the berm.  The noise basically is re-directed upwards for a while, but after a distance is back down toward the ground.  This would cause the berms to not be very effective for this purpose at this plant site.

• Third, again, the additional noise levels at most areas outside the Eastalco property would be insignificant

Question: What additional noise will we hear at the school?  What will our children be subjected to?
Answer: The additional impact at the school should be about 0.3db.  In reality that should be too small of an impact to be noticed by the children.

02/18/2006 08:24 AM