RUBBLE from the toppled Cockenzie Power Station chimneys is being crushed down and used to fill trenches and mine shafts on the site.

An estimated 74,500 tonnes of concrete from the demolition of the twin chimneys remains on the site and ScottishPower has revealed 97 per cent of it will be recycled and used to prepare the ground for future development.

Brown and Mason, which has overseen the demolition of the landmark power station and its iconic chimneys, remain onsite as the final stages of dismantling the structures continue.

Giant trenches on the site are steam cleaned to ensure any residual oil and hydrocarbons are removed before they are filled with the crushed-down rubble from the chimneys.

As our exclusive pictures show, the work is being carried out at the moment and the power station site is unrecognisable, with so many of the buildings now razed to the ground.

Along with the trenches, which would have formed part of the station’s drainage system, mineshafts which go 100ft into the ground are also being filled with the rubble.

As well as using the steam cleaner on the trenches, Brown and Mason has employed a giant magnet machine which lifts iron and steel from the rubble before it is crushed.

A spokesperson for ScottishPower said: “The removal of materials from site is a fairly intricate process.

"Wherever possible, different types of waste are segregated. For example, low grade steel would be separated out from cabling.

"Once there is enough of a particular waste, it is loaded onto a skip for recycling off site.

“Prior to leaving site, large steel sections are first cut into pieces that are suitable to go straight into a furnace.

“We also have machines that use magnets to remove iron and steel from the waste pile prior to it being loaded and crushed. After the brick and concrete has been crushed, rogue materials such as wood or plastic are hand-picked from the pile.”

The pictures show a trench being prepared for infilling, as well as a section which has already been packed with chimney rubble.

The water used to steam clean the trenches is passed through a 'siltbuster' which removes residual oils to ensure they do not end up in the Firth of Forth. The meticulous procedure of cleaning allows the firm to recycle so much of the material onsite.

The aerial shot shows the crushing operation in the foreground and the various trenches.

The spokesperson said: “Excellent progress is being made on the site and we estimate approximately 74,500 tonnes of rubble, not including the steel structures which are removed, is onsite and 97 per cent of that will be recycled.”

Contractors are expected to be off-site by the end of the summer. The long-term future of the site has yet to be decided.