At least two agencies have been investigating Caltrans' Foundation Testing Branch - whose technician, Duane Wiles, falsified bridge tests - for financial fraud.

In a recent interview, Robert Pieplow, Caltrans chief engineer, acknowledged his agency's ongoing probe concerning possible theft of state property and improper overtime claims. "We take matters of fraud, abuse, misuse of state resources, misuse of federal resources very seriously," Pieplow said. He would not provide details.

The Federal Department of Transportation has completed a similar investigation, he said, but t was confidential. That agency declined to comment.

Caltrans also recently initiated an audit of the Foundation Testing Branch, according to internal documents obtained by The Bee.

For now, the only details about possible financial fraud come from an anonymous whistle-blower who sent letters to the State Bureau of Audits in January 2009 and to former Caltrans Director Will Kempton in May 2009.

The letters alleged that in addition to falsifying tests of bridge foundations, Wiles might have exaggerated or invented overtime hours. According to Caltrans records obtained by The Bee, Wiles was paid nearly $39,000 for 925 hours of claimed overtime between July 2006 and June 2008 - a period during which he also falsified test data.

Wiles is also experiencing alegal challenge in his personal life. He was charged in San Joaquin County last year with a felony sex crime against a child. He remains free on $100,000 bail, awaiting a pretrial conference, according to court records.

Caltrans placed Wiles on administrative leave last week, after The Bee inquired about his work. He declined to comment.

The whistle-blower also claimed that Wiles' supervisor, Brian Liebich - a nationally known expert in the testing of underground foundation support shafts - directed technicians working on state time to "fabricate a large steel gate" for his private property near Susanville, in the mountains 185 miles northeast of Sacramento. He allegedly directed those technicians to transport and install the gate, and to build an A-frame structure on his property, using state equipment.

The construction took place between 2006 and 2008, according to dates on photos obtained by The Bee. They include images that appear to place state technicians and Caltrans construction gear and materials on the property. The Bee verified the presence of the structures and steel beams on Liebich's forestland.

Caltrans also placed Liebich on administrative leave last week. He did not return calls seeking comment.

Call The Bee's Charles Piller, (916) 321-1113. Follow him on Twitter @cpiller.

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