Banner: Laser Interferometer Gravitational Wave Observatory (LIGO), Hanford, Washington. Operated by Caltech, Pasadena, California, for laser testing of gravitational waves. Crystal Lok® applied to both 4 kilometer legs of the 14 foot diameter tunnels to seal corrosion cracking and seal against water intrusion. Toal length treated = 5 miles.
LIGO tunnel photo: Matheson Painting, Pasco, Washington
LIGO tunnel interior vacume and lasar equipment Photo: CalTech NOTE: Crystal Lok® pomeability test pressures were maintained for 400 hours, continuous. No leakage = 0 Permeability