The completion of remediation works on Haulbowline Island in Cork Harbour will "significantly enhance" the environmental conditions in the harbour as a whole, according to the Chief Executive of Cork County Council.
Work has been completed to contain waste on the former Irish Steel plant on the island.
The waste has been "capped" on site, using 47,000 tonnes of rock armour, 180,000 tonnes of subsoil and 37,000 tonnes of topsoil.
New additions to the site include playing pitches, walkways and cycle ways.
Speaking on RTÉ's News at One, Tim Lucey said "we are now looking at an extensive 30-40 acre recreational facility sitting across from Spike Island".
He said the area had become known locally as the slag heap, due to the amount of unauthorised dumping there over the years.
The site, officially known as the East Tip, contained around 650,000 cubic metres of steelworks waste that was deposited on a sand spit over a 40-year period.
Mr Lucey said the latest development, including biodiversity areas, will make the harbour more attractive to those in Cork and also for visitors from further afield.
He said there were no objections to the planning application for the project, which he attributed to working closely with local communities groups, including the Cork Harbour Alliance for a Safe Environment.
He added that the official opening of the park is planned for the May Bank Holiday weekend next year.
Mr Lucey told News at One that plans were underway to see the park linked back to Cork city through the development of greenways.
He also said work was ongoing in relation to additional cruise liner facilities at Spike Island.
Minister for Agriculture, Food and the Marine, Michael Creed TD, last week visited Haulbowline Island to mark the completion of the remediation project.