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Biological warfare


Bioremediation has found recognition tough in the lucrative decontamination market, despite the increasing cost of alternatives such as dig and dump. David Hayward catches up with one of the technique's leading proponents

DEEP beneath an abandoned Nottinghamshire gasworks, an army of microscopic fighters is waging war on a tar-blackened enemy - by eating them.

This is the battle of bioremediation and the fighters are like some sort of miniature SAS strike force - camouflaged as a secret mix of compost.

Cleaning contaminated land by this method involves mixing the soil with clean, hungry bacteria, plus a catalyst that encourages them to react with and absorb the dirty enemy. This can take place either above ground, after excavating the contaminated area, or in situ by injecting the clean mixture through tubes.

It is little wonder that one of Britain's leading specialists in the underground bacterial clean-up of contaminated land claims that ignorance and suspicion of a basically simple technique - one that has been around for decades - is this niche industry's main drawback to rapid growth.

Simon Martin, director of Response Bioremediation, feels frustrated by a lack of understanding from clients and from the Government's own regulating body, the Environment Agency. Moreover, he is annoyed with a licensing system that is 'embroiled in bureaucracy and designed mainly to generate a bit of extra cash for a financially strapped, under-resourced agency'.

'Acceptance of the technique by potential clients is slowly improving but there is still widespread suspicion about a process wrongly perceived as relatively new, ' claims Mr Martin. 'A major hurdle is not being called in early enough for us to be able to offer a viable alternative to dig and dump.'

This month, his own company is being devoured by Dew Pitchmastic, a group with a turnover some 40 times greater than Mr Martin's. But it is a friendly takeover and he is optimistic that both companies will benefit.

'It will allow Dew to offer developers a one-stop shop from site clean-up to new build, ' he says. 'As well as forming a new specialist arm of our parent company, we will continue to trade in our own right so there are real opportunities for us next year to double our current £3.6 million turnover.'

Response Bioremediation claims its Bio-Gel technique is one of the few that is put totally underground - leaving at least part of the site available for the developer after just a week or so.

In theory the complete reaction can take up to 20 weeks to totally kill off the nasties. But, Mr Martin argues, by adjusting the mixture's strength, staged decontamination can often allow the developer early access, making the process as quick as conventional dig and dump.

Other claimed advantages include a price that is up to 50 per cent cheaper, nothing being taken off site, no expulsion of noise or dust, plus the added sustainability bonus of completely destroying the contamination rather than just transferring it to a tip elsewhere.

Armed with this checklist, Mr Martin reckons the value of the bioremediation market could double in the next five years. It is currently worth £38 million a year.

Five years ago it was worth half that.

The Government has set a target for at least 60 per cent of the 3 million new homes urgently needed to be built on brownfield sites. With south-east England claiming both the most acute housing shortage - plus the fewest and most expensive landfill sites - Mr Martin's wish to move away from dig and dump may well be granted. But, he argues, the Government itself has proved a reluctant ally.

Every time his company moves onto a new site it needs Environment Agency approval through the issue of a separate mobile plant licence. These are not transferable between sites, which means Response, which won the industry's first such licence two years ago, now has a collection of 13 licences.

These licences can take three months to process, Mr Martin says, and each costs more than £5,000 to obtain and keep operational for a year. There is an additional charge of up to £10,000 lodged with the Environment Agency as a financial guarantee that the technique works.

'I am in favour of the licensing principle, as it keeps down the increasing number of cowboy companies that tarnish our industry's reputation, ' he says.

'But the current licensing procedure is an expensive, unnecessary nightmare, fuelled by bureaucracy and the Government's continuing ignorance of bioremediation.'

Speed and secrecy GIVEN TIME, indigenous bacteria in the soil will destroy localised organic contamination such as toxic hydrocarbons and phenols without assistance from humankind. They simply digest the polluted bugs, reducing them to harmless carbon dioxide and water.

But this reaction can take decades. To speed this process up, Response Remediation's technique involves injecting a mixture down through wells or hand-held lances direct into contaminated areas up to 9 m deep.

The injected mixture contains three ingredients and is site specific depending on the degree of contamination and how quickly the area needs to be cleaned.

Millions more natural, non pathogenic bacteria are added, obtained from a combination of up to eight separate sources, such as fermented compost or manure.

A catalyst and additional food supply, in the form of a liquid fertiliser, accelerates the reaction, while the company's own patented secret ingredient, known as Bio-Gel, completes the mixture.

This binds everything together as a sticky, cellulose polymer with the dual capacity to concentrate the attack and act as insulation, allowing it to continue performing in ground temperatures as low as 12 deg C.