PERMFILE47760

• Permit No: C1981010
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: BLASTING
• Section_Exhibit Name: APPENDIX L
• Media Type: D
• Archive: No

White Engineering Associates, Inc.
Report Vo. 79219-D
Utah International, Inc.
June 18, 1979
Page 4
• ~.
they conform to D/iti'Z where D is the distance from the blast to instrument
and W is the maximum charge weight per delay. Both the OSD1 limit of 1 in/sec.
and the scaled distance of 60 are noted on these graphs. .
Graph II uses the maximum charge weights per delay noted on the
blasters log, and Graph IIA uses the larger charge weights per delay noted
as two-thirds of the totals far the blasts of January 10.
Graph III is a study of the frequencies recorded from all of the
blasts at the stations where full waveform data were recorded. The peak
velocity amplitude is plotted as a function of the frequency at which it
occurred. Please note that both the peak particle velocity and the frequency
decrease with distance. It is further noted that all of the measurements on
the turbine pedestal show frequencies in the range of 3-4 Hertz while the
input frequencies were on the order of 1-2 Hertz.
Because of this study, it appears to me the fundamental frequency
of this power station structure may be close to 3.5 Hz. Once it was induced
to vibrate in response to a blast, it continued to oscillate at near maximum
• amplitude for several seconds. The maximum displacement for this structure
resulting from *_his vibration falls at 0.007 inch. This can be read directly
from the graph. 'The maximum acceleration is 0.0094 "g".
The blast of February, 1977, which was the opening blast, produced
a maximum displacement of 0.0036 inch, but the blast was a half mile closer
to the power plant than the blasts of January 10. The blast of September,
1977, which was of the same order as the blasts of January 10, 1979, in terms
of total pounds caused a displacement of about 0.0014 inch. The delay patterns
for both the February, 1977, and the September,1977,blasts provided much longer
durations for the total shots. In the case of the September, 1977, shot, the
duration was greater than one full second which allowed the seismic pulse from
individual delays to dissipate more completely before the additional delays fired.
Conclusion and Recommendation ~~•''-t=
In previous reports sae have stated that blast praJuced seismic effects
will be transmitted at perceptible levels for several miles. The results of
_ these tests corroborate these previous statements.
• The measurements obtained from the two blasts of January 10th were
generally higher than from previous I~lasts. The maximum charge weights per
delay were also much larger. L-4