The revelation adds further pressure on Victoria's Education Department to account for its use of public money following Fairfax Media's expose on Tuesday of a secret $28 million slush fund being operated by high-ranking bureaucrats in which funds meant for needy schools were instead used to pay for overseas travel, cars and boozy conferences.

It is also uncomfortable for the new Andrews government, with the Independent Broad-based Anti-Corruption Commission's investigation of the Education Department believed largely to relate to projects and financial transactions completed under the previous Labor government.

Fairfax Media is not suggesting Ms Pike has been involved in any corruption.

An ongoing Fairfax Media investigation can also reveal:

• One of the department's top former officials allegedly selling tickets to a Labor fund-raiser at departmental conference.
• Allegations from a former high-ranking education bureaucrat that funds meant for disabled students were diverted to pay for professional leadership programs for top officials.
• Confidential documents showing how the former Brumby government's $60 million contract for the Ultranet schools IT system was awarded to a company that had yet to fully develop or even register the trademarks for crucial software at the centre of its 2009 bid.

Fairfax Media has obtained a 2009 ministerial briefing written for Ms Pike and then Education Department deputy secretary Darrell Fraser which outlines the $7.6 million budget blow-out for the Bastow Institute of Educational Leadership building in North Melbourne.

The institute, which the briefing notes say was designed to service "aspiring and current leaders" within the department, was created in Ms Pike's Melbourne electorate.

Several senior departmental sources have told Fairfax Media there was no reason the institute could not have been housed at an existing facility or in partnership with a university.

The briefing attributed the increase in the institute's cost to the "design and implementation of interpretive and non-interpretive installations" and the global financial crisis.

It also said a decision by Ms Pike to cancel the planned sale of land adjacent to the site resulted in an estimated loss of $2 million. It is not known why Ms Pike, who did not return calls to Fairfax Media, blocked the sale of land.

The briefing noted that the cost of establishing the institute would be offset by a $1.3 million commitment from computer supplier Lenovo to provide the "technology fit-out". The offer from Lenovo raises a potential conflict of interest scenario as it also bids for contracts to supply computers to various government departments.

Another government document from 2008 reveals the department's then deputy secretary, Jeff Rosewarne, approved an extra $900,000 to remove asbestos and other hazardous materials from the site.

Fairfax Media's publication on Tuesday of a confidential 2011 audit of the Education Department's $28 million "banker schools" fund and the lack of invoices to account for much of the money has prompted the state opposition to go on the attack.

Former Liberal treasurer and Malvern MP Michael O'Brien said Labor had questions to answer about the slush fund.

"This appears to have been a slush fund of sorts that was operating under Labor and it appears it was wound up under the Coalition government," Mr O'Brien said.

The Liberals are also likely to pressure the Andrews government to explain Labor's management of the Ultranet project, which was abandoned last year by then premier Denis Napthine after its cost blew out from $60 million to $180 million.

The project went ahead despite probity concerns over the 2008-09 tender process and warnings from Premier and Cabinet and Treasury not to proceed.

Fairfax Media recently revealed how three former senior Education Department officers and one still-serving regional director bought shares in the Darwin IT company CSG Limited, which was awarded the Ultranet contract.

Fairfax Media also revealed how Ms Pike's ministerial office received a legal letter from an unsuccessful Ultranet bidder, ASG Group, which threatened to subpoena Mr Fraser to give evidence in a case the Perth company planned to lodge against CSG Limited.

CSG is believed to have paid ASG Group about $4.5 million to settle the matter soon after the legal threat was sent to Ms Pike's office.

CSG, which employed Mr Fraser after he left the department in mid-2011, has denied any wrongdoing in relation to the Ultranet project and says it has not been contacted by  Independent Broad-based Anti-Corruption Commission investigators.

A spokesman for the department said the Bastow Institute was created in North Melbourne because it was a central location and the site of a derelict school designed by the architect it was named after, Henry Bastow, who oversaw the creation of more than 900 schools across the state in the 1800s.