Easter weekend tourists who arrive at the gates and pay their pounds 8.95 - or pounds 4.95 if they haven't come by car - will find what at first sight looks like a giant green theme park built in the middle of what was formerly one of Britain's most devastated colliery wastelands. Surrounded by reclaimed spoilheaps at Conisbrough, at the confluence of two of Yorkshire's most polluted rivers, the Don and Dearne, it appears to be a spreading mix of hi-tech exhibitions about the environment, post-modern architecture and new landscaping.
But what makes it exciting for some is that it is about a single idea, vital for the 21st century, but one which has hardly permeated the public consciousness: sustainable development. This idea, of growing without screwing up the future, informed the Earth Summit of 1992. It is at the heart of theGovernment's environmental policy, and yet, on the Clapham omnibus, it does not enter the conversation. So Jonathan Smales, a former Greenpeace campaigner, has persuaded the Millennium Commission to invest pounds 50m, and is on course to find another pounds 50m, to create a theme park that illustrates how it can be achieved.
The Earth Centre's first phase, to be opened by the Secretary of State for Culture,Chris Smith, on 26 March, is built around four exhibitions devoted to the Earth, its fragility and threats to it.
Even the loos will be sustainable. The 60 or so lavatories on the site operate by vacuum suction, as in aircraft, and need only a tenth of the water of conventional ones.
The sewage is not only recycled into irrigation water and compost, but visitors will see it happening in a water treatment plant bursting with tropical plants and flowers, which are part of the process.
Energy in the buildings will come from sunlight and an underfloor natural air heating system resembling a Roman hypocaust. Pesticides will be virtually absent. Every drop of water will be recovered and re-used and even the colliery spoil on which the site stands has been reclaimed by using sewage sludge as a compost, rather than by bringing in topsoil from somewhere else.
But it is not all about the environment, Mr Smales the centre's chief executive, points out. The first phase of the site is providing jobs for 150 people, many of them former miners from the two local pits that closed in the Seventies and Eighties. Twenty million people live within a two- hour drive, Mr Smales says and the site is close to the high-speed East Coast railway line.
Mr Smales said he was perfectly happy to have his creation labelled a green theme park but stressed there was more to it. "We've gone beyond environmentalism," he said. "This is not just about landscape remediation and wildlife, it's about people and jobs and where the industries of the future are going to come from."Reuse content