Repairs to cracks found along the 1.4 billion dollars, 20-mile light rail project in PHoenix are nearly complete, but deciding who's to blame is still far from done. Officials found fissures up to 7.5 in. wide across three of the project's five line segments during routine inspections, in January, consultant Zeta-Tech Associates, Cherry Hill, N.J., was hired for 60,000 dollars to conduct a three-month investigation to determine the cause and recommend repairs. High heat from handheld plasma welding torches used to cut drainage openings into the line changed the steel's structural properties resulting in brittle-ness and microscopic cracks that worsened with expansion and contraction during seasonal weather changes.
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