November 21, 2000

BIRMINGHAM, AL — Rock-hard limestone formations at the construction site for the North Pavilion must be cleared away to complete the site excavation. The only way to remove the rock is through the use of low-level explosives, or "blasting." The same process was used when other buildings with deep basements were constructed, including the West Pavilion, Spain-Wallace Tower and the Wallace Tumor Institute.

Blasting will begin Wednesday, November 29 and continue through mid-February 2001. Blasts will occur once a day, at or about noon.

Special precautions have been taken to avoid undue vibration from the daily blasts, according to Tom Allen, project manager of the North Pavilion project. Eight seismograph machines will be placed around the site to monitor levels of vibration. In addition, contractors have drilled deep holes into the limestone to reduce the transmission of vibration from the blasts.

Two of the seismographs will be placed in the radiation oncology unit in the nearby Wallace Tumor Institute. Blasting will take place at noon so patient care activities at WTI are not interrupted. To ensure minimum disruption to those patients, the contractor will alert the staff in radiation oncology 30 minutes before each blast.

"Due to state regulations and city code, this process can only be done during weekdays and only between the hours of sunrise and sunset," Allen says. A series of air horn signals will be used before and after a blast.

Five-minute warning: 5 short horn blasts
90-second warning: 2 long horn blasts
Firing: 3 short horn blasts
All Clear: long horn blast.