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The operator has committed in item 4, pa¢e D4 of their permit to the following: Maximum of 360 pounds of explosive per borehole; 12 foot burden and 15 foot spacing; Average 30 feet depth; Minimum of 2 feet of stemming per borehole; No blasting within 50 feet of buried telephone cable; No blasting within 1,000 feet of a public road; No blasting within 1,500 feet of a dwelling; No blasting at night; Seismic monitoring will be conducted in order to insure that the vibration limits are not exceeded; A pre-blast survey will be conducted on the only dwelling located within one mile of the site. The Pueblo County Special Use Permit requires the following No blasting between 6:OOPM and 8:OOAM; No blasting on Sunday Staff Recommendations: • For burden and spacing use a range of values, for example 10 feet to 20 feet for both burden and spacing. • For depth of borehole use a range of values, for example 10 feet to 40 feet. • Commit to stemming more in line with accepted blasting guidelines (.7 x burden), or possibly commit to a minimum of 25% to 30% of the borehole depth will be stemming, or both, or provide rationale for reduced stemming; • Consider performing apre-blast survey of all structures owned by people who have written letters expressing concern over blasting. The pre-blast survey should be conducted by a third party, and should be recorded photographically; on video tape; and in written format. • Consider seismically monitoring all structures above for the first one or two blasts to establish a baseline and correlation with the main seismograph, so that future blasts may be monitored using only the main seismograph. • As the Division has received written communication that there is an historic adobe structure north of the site, the operator should consider seismic monitoring of this location for some period of time 14