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can be utilized to design a blasting event. It requires "only that the distance from the shot to the structure of interest is related to the maximum charge weight per delay, as a square root scaled distance." In other words, if the distance from the shot point to the structure of interest is known then the blaster can calculate the maximum charge weight allowed for a particular blast (maximum charge weight without exceeding any threshhold limits). The measured distance from the blast area to the Bowie residence is about 3220 feet. Therefore, the maximum allowed charge weight per delay is 3,428 pounds (this assumes an 8+ millisecond delay). Holnam, Inc., the operator, submitted a packet of blasting data for the dates the Bowies said they were home [o observe the tremors from the blasting activities (plus two (2) blasting shot records for November when instruments were set up a[ the Bowie residence). Instruments were used during 8 blasts [o record ground motion and airblast. Instruments were located at [he north gate ([he north part of the permit area near highway 50) during 5 events, at the primary crusher site during 1 event and at the Bowie residence during 2 events (November 5 & 14, 1997). During the two November blasts, the instruments measured peak particle velocities of 0.128 in/sec and 0.184 in/sec on November 5th and 14th respectively. These readings are well below the 1.0 in/sec threshhold limit so, therefore, the probability [hat these blasting events caused any ground motion damage to the Bowie structure is near zero. However, airblasts registered 112.1 dBL on November 5th and 109.6 dBL on November 14th. These are below [he threshhold limits (129-133 dBL) but are within annoyance range. In all probability, although not reported, these blasts were heard (felt) by the Bowies. Obviously, since the Bowies have not reported any window damage, the airblasts have not been a problem. The Bowies reported four (4) instances where the blasts (tremors) were "big" or "the biggest". The "biggest" event occurred on September 9, 1997. This was a 60 shot event which used 471 lbs of explosives per hole in each of the wet holes (7) and 319 Ibs of explosives per hole in each of the dry holes. The maximum charge weight per delay was approximately 1,900 pounds (well below the allowed 3,428 pounds). Airblast and ground motion was not recorded during this event. But, given that [he charge weight per delay was well below the allowed charge weight, the probability that excess ground motion occurred is extremely low. Since the event was sizeable (60 holes) it is possible the Bowies felt an airblast. Of course, this is only speculation on my part. Instruments were placed at the north gate during the three "big" events. Peak particle velocities measured 0.132 in/sec, 0.108 in/sec and 0.183 in/sec during the October 3,7 and 16, 1997 events, respectively. The north gate is approximately 1900+ feet northeast of the quarry area and the quarry area is approximately 3200+ feet southeast of the Bowie residence. Airblasts measured 113. I dBL, 117.2 dBL and 128.5 dBL during the October 3, 7 and 16, 1997 events, respectively. No[ one exceeded the threshhold limits but all three were within the annoyance range. Most likely, the Bowies experienced the airblasts during these events. Based on the packet of blasting information that was submitted, it is clear that the airblast and ground motion threshhold limits were not exceeded during any of the recorded events; including the two events that were monitored at the Bowie residence. The maximum allowed charge weight per delay (3,428 pounds) was never exceeded during any of the unrecorded events. Since none of the limits were exceeded, the probability [hat these blasting events caused any damage to the Bowie residence is near zero. The Bowie family should realize that all homes eventually crack because of a variety of environmental