U.S. Naval Observatory Dome Receives A Face-lift

      Pentek, Inc.                         Serrano Painting, Inc.

The U.S. Naval Observatory Dome, a few miles west of Flagstaff, Arizona, recently underwent a face-lift to improve the appearance of the exterior of the dome and preserve its structural integrity. The presence of aging coats of lead-containing paint in a public place warranted that the lead paint removal proceed in a manner that was safe both to the environment and to the workers performing the deleading.

The Observatory was established in 1955 and operates three optical telescopes, the largest of which is the 61-inch astrometric reflector. This facility houses the premier ground-based telescopes for the measurement of stellar parallax. The Dome sits over 6,000 feet above sea level and can experience severe weather on occasion (http://www.usno.navy.mil).

Serrano Painting, an Arizona based painting contractor, was contracted to remove 11,000 ft² of lead-based paint from the exterior of the Dome and to prepare the steel underneath as part of the Dome refurbishment. Serrano Painting was careful in selecting a lead abatement technology for the Observatory Dome project. Serrano looked for a methodology that would specifically eliminate the need for full containment structures--a requisite of traditional coatings removal techniques such as abrasive blasting. These tent-like structures, along with associated air filtration and dust collection equipment, require lengthy set-up and are very costly to maintain. Moreover, if the containment succeeds in protecting the surrounding environment, it increases the potential exposure to the workers operating inside that containment. It was also realized that obstructive containment tenting or visible emissions of dust diffusing from the worksite would earn swift and negative attention. The potential for escaped lead-contaminated air emissions during blasting operations also warrants the use of full facepiece respirators by abatement workers operating in positive-pressure mode.

Serrano Painting chose to use a shrouded power tool system designed by Pentek that safely removes lead-based coatings and captures the hazardous airborne dust and debris. These systems have been tested and approved by the Department of Energy (DOE), Environmental Protection Agency (EPA), OSHA, and Housing and Urban Development (HUD). Shrouded power tool technology effectively prepares structural steel for new coatings, while simultaneously controlling all emissions in excess of 99.5 percent. Thus, the need for containment and respirators is eliminated by preventing the potential for lead poisoning to the environment and workers. "Inspectors on-site were so impressed with the systems ability to control emissions that they invited other facility owners to view the removal project", said Serrano.

Both the Roto-Peen Scaler and Corner-Cutter needle gun utilize a mechanical, air-driven process that cleans surfaces to a bare substrate, while the above mentioned VAC-PAC HEPA filtered waste collection unit simultaneously captures dust and debris and transports the waste it into an on-board 55-gallon drum. The VAC-PAC is equipped with several engineering controls built into the system to insure that exposure to hazardous airborne particulate would be minimized. Those features include patented dustless drum changeout procedures, safety interlocks, visual and audible full drum alarms, and onboard gauges that allow you to monitor the performance of the VAC-PAC during operation.

Dust-free surface preparation is a viable alternative to abrasive blasting for large industrial structures like domes and bridges. For Serrano, waste minimization, environmental protection, worker safety, and the elimination of other less identifiable liability costs made multi-tool shrouded power tool system an option he could not ignore.