MPs have approved an additional $400,000 in costs to resurface the airport and bring it up to new fire safety standards.

The supplementary amounts for the past 2009-10 financial year are $150,000 for 'Resurface Taxi Ways and Aprons' and $250,000 for 'Fire Barrier Requirements'.

The subsidies, under Airport Operations, are to be made under Government's Capital Account.

A Government document explains that the Total Authorised Figure (TAF) for the resurfacing work was $18 million, in addition to $1.7 million for a Runway Grooving project.

The total cost of this combined project was $19.8 million, in December 2008.

The additional $150,000 is a "minor over-expenditure" for "a late stage payroll tax assessment in December 2008 of approximately $321,000".

Government explained: "The payroll tax amount however was not reflected against the project until 2009/10."

It says the additional $150,000 has already been offset from existing capital projects.

Shadow Education Minister Grant Gibbons asked: "Why is Government having to pay payroll tax to a private company to resurface the airport? Was it left out of the original contract?"

Premier Ewart Brown, Tourism and Transport Minister, replied: "Yes."

He said: "It is not unusual for a contractor to understate the cost of the payroll tax and other things as well. Any Member who is deeply interested in the specifics can make contact (with me). There's no effort here not to be anything more than transparent."

The TAF for the 'Fire Barrier Requirements' meanwhile, was $650,000. Government says the additional $250,000 is needed to cover the costs of replacing the contractor.

Government states: "This over-expenditure is directly related to replacement of contractor. Due to the inability of the original contractor to fulfil the contract.

"As a result they were dismissed and replaced by a new contractor at an additional contract value of $462,000.

"However, it is anticipated the additional cost will be offset by withholding of the retentions from the original contractor and the Government's legal pursuit for breach of contract."

Dr. Brown said a local firm was awarded the contract but was "unable to meet the performance deadline and was terminated". After a new Request For Proposal was issued, Isis was chosen for the contract. However, it needed an additional $250,000 to complete the job.

"This will be funded from savings from other capital projects," he said.

"Government will also recover costs from the original vendor's failure to perform."

Shadow Works and Engineering Minister Patricia Gordon-Pamplin asked: "Was there a Performance Bond by the first contractor which would offset his failure to complete the job? If there was a Performance Bond you would have had some collateral to offset this."

Dr. Brown replied: "There was a $1,000 a day Performance Bond in place."