Condit Dam Removal Condit Dam Removal - Access Washington

Condit Dam Hydroelectric Project
Final Supplemental EIS
Table 4.8-3 (Continued)
Noise Modeling Results
Action
Coffer Dam Removal
Wood Stave Pipeline Removal &
Disposal
Concrete Surge Tank Removal &
Disposal
Power Facilities Removal & Disposal
Post-Removal Management
Management of Sediment and Woody
Debris following Dam Removal
Note:
a. dBA = A-weighted decibels
Distance
(miles)
SUMMER
Cumulative noise level
(dBA) a
WINTER
Cumulative noise level
(dBA) a
1/8 34 34
1/4 27 28
3/8 23 24
1/2 20 21
5/8 18 19
3/4 16 17
7/8 14 16
1 13 14
1/8 33 33
1/4 26 27
3/8 22 23
1/2 19 20
5/8 17 18
3/4 14 16
7/8 13 14
1 11 13
1/8 34 34
1/4 27 28
3/8 24 24
1/2 21 21
5/8 18 19
3/4 16 18
7/8 15 16
1 14 15
1/8 33 33
1/8 27 27
1/8 24 24
1/8 22 23
1/8 21 22
1/8 21 21
1/8 20 21
1/8 20 21
1/8 34 34
1/4 27 28
3/8 24 24
1/2 21 21
5/8 18 19
3/4 16 18
7/8 15 16
1 14 15
The cumulative noise levels in Table 4.8-3 were calculated using the equation below. It
should be noted that sound levels do not combine arithmetically. For example, 21 dBA of
noise received at a given location due to operation of a pickup, combined with 40 dBA of
noise received at the same location due to operation of a dozer does not result in a cumulative
4.8-8