A series of isolated pits several metres long and deep and about one metre wide will be excavated over the site by contractor Dixon and Dunlop so environmental consultants URS can undertake testing to determine what area is contaminated and to what degree.
Wellington City Council Senior Project Manager Tim Harrod says a coal-fired power station occupied the site of the Kilbirnie fire station - across the road from the park - until it was demolished in late 1968.
"Coke ash from the power station was deposited on what is now Cobham Park, and the ash contains heavy metals which can be harmful. We are required to remove any contamination we disturb during construction to a suitably contained landfill such as the Southern Landfill.
"We know there will be some degree of contamination on the airport side of the site - we found a thin layer during our original testing two years ago - but investigations could extend further across the site, depending on the extent of contamination we find."
Tim stresses the work is not the commencement of construction activities for the ICSC. "Resource consent hearings were completed in December and a decision by the independent commissioners is expected in mid January. We need to undertake testing of the site now to fit anticipated project timeframes and our sportsgrounds schedules."
The testing work will not be noisy, and any excavated material will be returned to its original position at the end of each day. The work is not expected to have any impact on Cobham Park neighbours, but if neighbours have any questions or concerns, they can call (04) 499 4444.
In addition to the test pits, there could also be some drilling on the site. The work is expected to be completed within a month.
Organised sports on Cobham Park have ceased for the second half of the summer, and casual users are encouraged to use Kilbirnie Park or Cog Park while testing takes place. If the ICSC resource consent is granted, no further sports will be taking place on the site until the Centre is opened, in the spring of 2010.