The project, hit by controversy over rare newts and Hanson's pounds 100,000- a-year contributions to the Tory party, will build 5,000 homes for 13,000 people on around 2,500 acres of derelict clay excavations three miles south-west of Peterborough, in north Cambridgeshire.
Around 12,000 jobs will be created over the 15-year development, which straddles the current Huntingdon and Peterborough constituencies of John Major and the Tory chairman, Brian Mawhinney.
Last year the Worldwide Fund for Nature threatened to take English Heritage to court for breaking European habitat regulations after it agreed to let Hanson shift 30,000 rare great crested newts, the UK's largest colony, to a new 296-acre reserve a few hundred yards away.
The protected species colonises water-filled pits, a legacy of over 100 years of digging by Hanson's London Brick operation.
Operation Great Crested Newt started more than three years ago, with staff scooping up bucketfuls by torchlight during the mating season. Hanson has spent pounds 750,000 so far on catching them and expects the end cost to be pounds 1.75m - pounds 58.33 per six- inch dinosaur lookalike.
The private development , in gestation for 10 years, has also been dogged by bickering between Labour and Conservatives on Peterborough council, the only Tory minority administration supported by Liberal Democrats.
Labour wanted the development to be built on agricultural land west of the city, a Tory stronghold, but this was rejected. "We suspect Hanson got the deal because of its donations to the Tory party," a leading Labour councillor said.
Neither Mr Major nor Dr Mawhinney will represent the new Peterborough Southern Township at the next general election. After boundary changes it falls wholly in Peterborough, but Dr Mawhinney joined the "chicken run" last year to thesafer North Cambridgeshire seat.
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