Blast planned for once each weekday for four to six months.
As part of the excavation required for construction of the Science and Engineering Hall, once-daily controlled blasting activities are planned for weekdays beginning in March, and will continue for four to six months. The extent of the blasting will depend on the amount of rock at the site—located between 22nd, 23rd, H and Eye streets—as well as other site conditions.
This type of work is common in D.C. for construction of new buildings in areas where rock formations lie near the surface, said Alicia Knight, senior associate vice president for operations. Controlled blasting also occurred at 2200 Pennsylvania Avenue, now home to The Avenue apartment and retail complex, and at the Institute for Peace building at 23rd Street and Constitution Avenue, NW.
“Controlled blasting activities were always anticipated as part of this project. We have put into place protocols to monitor noise and vibrations to ensure compliance with regulatory limits and also to ensure the integrity of adjacent structures,” Ms. Knight said.
The blasts are expected to occur at approximately 10:30 a.m. each weekday. Air horns will sound at 15, five and one-minute increments prior to each blast and following the blast to indicate “all clear.” Weighted mats will be used on the blasting site to control dust and vibrations. Blasting activity may not happen on every weekday, depending on excavation progress.
The noise level from the blasts is expected to be comparable to a large truck passing by. Those very near the construction site may also feel a vibration comparable to a door slam or a large truck driving down the street. In addition, weather conditions, such as high humidity or the presence of cloud cover, can cause the air movement from a blast to seem more severe than under other weather conditions.
Residential housing and nearby office buildings will not be directly affected by the blasting. However, those near the area may hear the air horns and the controlled blasts. Individuals near the construction site when an air horn sounds should follow instructions from site personnel and obey any additional signage that may be posted.
Sidewalks adjacent to the site may be closed temporarily during the blasting events, beginning at the five-minute air horn. Adjacent streets also may be temporarily closed at the direction of D.C. Metropolitan Police, beginning at the one-minute air horn.
For detailed updates on Science and Engineering Hall construction, visit the GW Neighborhood website’s Square 55 page. To see a video of controlled blasting during construction of The Avenue in 2008, visit GW’s campus development website at www.neighborhood.gwu.edu/cd.