The talk around South Silver Spring lately has been the bedrock blasting at the 1200 East-West Highway construction site. One can only imagine that the decision to do a once-daily blasting instead of eight hours a day of jack-hammering was at least partially influenced by the outrageous noise that was 1200 Blair Mill Rd for months on end.

As noted in a previous post, the blasting is preceded by a series of warning air-horns. After the blast itself, a short air-horn is sounded.

I recorded the attached video from the top floor of the MICA Condominiums this afternoon. It seems at least from my position that the air-horn blasts are far louder than the explosion, but I would think that closer to ground level you could feel the explosion more.

The site at 1200 East-West highway is scheduled to be completed in 2009, and will provide 247 residential units as well as significant ground-floor retail.

Megan from Eastern Village brought this to our attention on the Yahoo! Group this afternoon:

In case you live in the neighborhood but not in one of the buildings that were formally notified: the construction project adjacent to the Giant supermarket has hired Air Power Inc (contact: Clifford Leiter, 703-471-4071) to blast every workday at 2 p.m. for approximately 4 months. This is to remove the bedrock under the site to build their underground parking garage. (The project adjacent to MICA chose to
jackhammer it away instead, and it has taken nearly a year of 40+ hrs/wk jackhammering -- you may have noticed this lovely sound. So I suppose one explosive blast per day is better...)

Here are the warning air horns they will sound:

• 15 min warning - one long horn sound
• 5 min warning - three short horn blasts
• Blast Signal - five short horn blasts; an explosion (lasting two seconds) will occur within one minute
• All-Clear - one long horn sound

I am just summarizing what was handed out to the residents at Mica; I don't have any inside info. (I live at EVC, and I'm a little annoyed they didn't bother to formally notify us, because it's a pretty startling thing to hear/feel, even a block away!)