Re: Environmental Technology

[Lenny Siegel <lsiegel@igc.org>]

CASTLE AFB TREATMENT CHOICE

 Castle Air Force Base, near Merced in California's Central Valley,
is a "Superfund" National Priorities List site undergoing closure. The
base's latest environmental newsletter reports that the Air Force, EPA, and
Cal-EPA have agreed to change treatment technologies for groundwater
contaminated with TCE (trichloroethylene). When pumped to the surface,
the water will be run through granular activated carbon filters, instead of
air strippers as previously planned.

 The newsletter reports, "'New data shows lower contaminant
levels than previously anticipated,' said Brad Hicks, [Air Force] remedial
project manager.... 'That makes carbon adsorption more cost effective
than air stripping while being equally protective of human health and the
environment.'

 "Another cost savings comes from the base already having four
granular activated carbon (GAC) vessels previously used at other cleanup
sites on the base.

 "'Aside from the cost issue, GAC technology is simpler than air
stripping and can be more efficient,' said Hicks. 'With a GAC system, we
don't have to contend with treating air emissions like we do from an air
stripper. It's strictly a liquid system.'"

 This is a good example how a strong regulatory framework - in
this case, air quality rules that restrict emissions from cleanup equipment -
can make the more environmentally sound remedy the more cost effective
remedy.