PROVIDENCE — The Department of Transportation’s chief engineer, Edmund T. Parker, was placed on paid leave from his $143,187-a-year job yesterday amid a widening state and federal probe of the state road-building agency’s contracting practices.

Speaking at an impromptu news conference, Governor Carcieri confirmed that he has now asked both the state police and the state’s top federal prosecutor, U.S. Attorney Robert Clark Corrente, to investigate “potential wrongdoing” at the DOT.

Carcieri said he asked the task force he assembled last month, in response to news accounts of “outrageous” overhead payments to contractors for staff, such as the now infamous $102,858 typist, to “turn over to the state police and the U.S. Attorney’s office any documents related to DOT contracts.”

The governor said the Federal Highway Administration has also promised to “begin a review.”

The announcements followed a private morning huddle at the U.S. Attorney’s office among Corrente, state police Maj. Steven O’Donnell, Carcieri’s deputy chief of staff, John R. Pagliarini, DOT Director Jerome F. Williams and members of their staffs.

By late day, Carcieri had issued a statement that said: “Over the last few months and weeks, I have become increasingly alarmed about information being uncovered at the Rhode Island Department of Transportation.

“After high overhead rates in one contract were exposed, we began a review of all other DOT agreements to see if we could uncover any other, similar problems…Unfortunately, the more we looked, the more we found,” Carcieri said.

Citing issues raised in recent Providence Journal stories, Carcieri listed among his concerns:

•The “discovery” that Parker, the DOT’s longtime chief engineer, voted in August 2005 to recommend the Plexus Corp., a company co-owned by his “step-nephew” David A. Giardino, for a $9-million contract to do the kind of work that neighboring states say they leave to their in-house staff: construction-schedule monitoring.

(In this role, Plexus employees — and occasionally Giardino himself — periodically sat across a table discussing Route 195 construction issues with Cardi contract administrator Nicholas Giardino, who is his father, Parker’s brother-in-law and a 1966-85 DOT employee with an $870-a month state pension.)

•The disclosure that another senior DOT employee, deputy chief engineer Frank Corrao, ordered subordinates to change the evaluation scores on competing bidders “to strengthen the case for hiring Plexus.”

•The extension in time, scope and money of relatively small contracts that morph into huge ones without ever being rebid, including the first of the Plexus contracts.

Awarded in 1997 as a $1 million, 30-month contract to help install a financial-management tracking system, the contract grew over a decade into what Carcieri yesterday described as an $8.5-million source of business for the company without ever again going out to bid. New assignments included a new bridge-design policy manual.(Earlier DOT reports had pegged the value of the contract so far at $6.6 million.)

While Plexus’ role in the daily operations at the DOT expanded significantly during his tenure, Carcieri also cited, as evidence of the long-running DOT way of doing business, a contract first awarded to Gordon R. Archibald Inc. for the Quonset Point Improved Access Design on July 1, 1982, for $361,423.

Since then, “it has been extended 233 times and its total value now exceeds $20 million,” he said.

“Neither of these contracts was ever rebid. Instead, DOT officials simply amended them to allow the new work to be performed under the old contract. This is not only poor management,” Carcieri said. “It appears to be a violation of state purchasing laws.”

In an interview, he acknowledged concerns about a more recent contract awarded Commonwealth Engineers & Consultants Inc. to study options for replacing or repairing the deteriorating Sakonnet River Bridge, a popular link between Southeastern Massachusetts and Aquidneck Island.

Commonwealth’s original contract was for $449,462. Since then, DOT spokeswoman Dana Alexander Nolfe said there have been “63 approved change orders for a total of $22 million for Commonwealth Engineers & Consultants and their sub consultants.”

“Sure some of it played out on my watch,” Carcieri said.

Asked whether he blamed former DOT Director James Capaldi, who retired in late December, Carcieri said: “It looks like some of them even predated him. All right, he did continue the practice … and so the question is: why? He’s been there a long time. A lot of them have been there a long time … . It seems to me they’ve gotten used to doing things they shouldn’t be doing.”

Swarmed by reporters in the State House rotunda, Carcieri had to switch gears quickly after leading off a scheduled news conference on a Big Brothers of Rhode Island fundraising event featuring the “World’s Greatest Chocolate Chip Cookie.”

One of several heated exchanges with television reporters began with this from Channel 10’s Bill Rappleye: “But you’ve been governor for nearly five years. It took a newspaper article to reveal these…?”

“No,” Carcieri said. “We got a new director, for starters, who’s been digging. We found out.”

“The old director was your director,” Rappleye persisted.

“I understand that,” Carcieri said. “You appoint people. Either they get the job done or they don’t and it appears that the job wasn’t being done. So we got a new director…”

Apprised in a voice mail of the governor’s comments yesterday, Capaldi, who retired in late December with a $113,192 state pension after more than three decades at the DOT, did not respond to requests for comment.

Capaldi currently works as a transportation services manager for the Louis Berger Group, a DOT contractor.

Asked yesterday if he called in the state police and federal investigators because his own inquiry had turned up evidence of wrongdoing, Carcieri said: “There are symptoms, all right? And when I sat with [state police Supt. Brendan Doherty] and talked about it, we agreed — he agreed — that there was enough to open an investigation.

“The investigation may come to nothing,” he said. “We may find there has been no wrongdoing. Just some bad practice, bad management, all those things could be going on. But I want to get to the bottom of it.”

Williams, a former deputy director in the Department of Administration who took over the DOT’s reins in late December, said he placed Parker, 59, on an indefinite, paid leave because it seemed prudent to do so while there is a state police investigation into “areas where he is directly involved.”

Added Carcieri: “Given the gravity of these concerns, and in light of his involvement in these contracting decisions, I have also instructed DOT to put Ed Parker on administrative leave with pay until a more thorough review of his conduct can be performed.

“Let me be clear. I am not prejudging the results of this review. But given his role in many of the contracts we are investigating, I do not believe he can continue to serve in that position while the investigation is ongoing.”

Parker has worked for the DOT since he was first hired as an associate civil engineer in November 1971.

Williams said he has not yet decided who will take Parker’s place. But he acknowledged “a concern” that Parker’s deputy, Corrao, initially said in an interview, in his presence, that he knew nothing about the rescoring of bidders for the $9-million construction-monitoring contract that went to Plexus. A member of the in-house evaluation committee later said Corrao himself urged the committee to make the spread wider.

“There is a concern there,” Williams said. “That is something I am going to handle internally.”

Journal staff writer Mike Stanton contributed to this report.

kgregg@projo.com