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a notification at each of the structures. Western Fuels also published the notification in three newspapers distributed in the mine locality. Hundreds of pre-blast surveys were conducted in response to the notifications and the surveys are maintained at the mine site. The approved Colorado program states, "If a structure is renovated or added to, subsequent to a pre-blast survey, then upon request to (DMG) a survey of such additions and renovations shall be performed...". Western Fuels exceeds the requirements of the Colorado program by directly notifying owners of newly constructed or renovated structures of their eligibility for apre-blast survey. Western Fuels has also exceeded the program requirements by conducting additional surveys on structures where it has been a number of years since the initial survey and the owner of the structure has requested it be surveyed again. Public Notice of Blasting Schedule Western Fuels published a blasting schedule the week before this inspection occurred; March 13, 1997. The blasting schedule was sent to owners and residents of structures within one-half mile of the blasting area around March 31, 1997. The blasting notice addresses the location of blasting, time of blasting, access control, audible warning signals, and a description of unavoidable hazardous situations. The blasting notice contains all the information required by the Colorado program. ~ Surface Blasting Requirements , Blasting has been conducted within the time periods as set forth in the blasting notification. I was not present during a blast to monitor the audible warning signals, but residents confirm that the signals are sounded prior to blasting. Western Fuels stated that residents closest to the blasting area are notified prior to each blast and this was verified. Some residents have requested that Western Fuels not notify them prior to blasting. The blast records reviewed do not indicate any violations of the maximum standards for airblast limitations or peak particle velocities. Western Fuels stated that four seismographs are placed in the field prior to each blast. Blasting records for the time period that OSM's seismograph was in the field were reviewed along with Western Fuels's seismograph records. Not all seismographs produce a record for each blast because not all seismograph are triggered by the blasting. No damage to property outside the permit area was observed in those areas inspected. Flyrock was not observed outside the permit area. I observed the furthest piece of flyrock to be twenty- nine paces from the back of one of the blasting areas. Records of Blasting In reviewing the blasting records, I noted one potential problem. The blasting records did not specifically indicate the total weight of explosives per hole. I contacted the DMG inspector after the mine site review and he stated that because the geology is uniform and the topography is relatively flat, the weight of explosives per eight-millisecond period (combined with the number of holes per eight-millisecond period if applicable) actually reflects this figure. This was the response