DOWN a narrow bumpy lane off Lim Chu Kang Road is a park like no other.

Small hills of old tyres, compost and construction debris dot the 30ha landscape, while lorries trundle noisily among them, like busy ants, picking up and dropping off loads.

It may not be listed in most street directories yet, but business at Sarimbun Recycling Park is booming - not bad for what used to be a landfill.

Just four years ago, there was only one company there, turning horticultural waste into compost.

Now there are seven, turning scrap tyres into rubber floorings for playgrounds and gyms, producing fertiliser, and recycling construction debris into building materials and other products.

Together, they drummed up $12 million worth of business last year.

There are more coming.

The National Environment Agency (NEA) told The Straits Times that three more companies have started moving in.

Another two will join them by the end of the year.

When these new firms start operating at full capacity, the NEA expects the park to recycle up to one million tonnes of waste a year.

This is nearly half of what Singapore recycles, and a fifth of the waste thrown out every day.

The recycling park was opened in 1995, on the edge of a former landfill, closed in 1992.

The waste is transported there by collection companies. The Sarimbun firms then process the waste into usable forms before reselling or exporting it.

Collection companies found greater incentive to recycle, when disposal fees for landfill or incineration went up in 2001 from $67 per tonne to $77 per tonne, making it cheaper to turn to recycling companies instead.

This is part of the NEA's strategy to increase the proportion of recycled waste to 60 per cent by 2012.

Last year, Singaporeans threw out more than 4.8 million tonnes of rubbish, of which 45 per cent was recycled, most of it from the commercial and industrial sector.

Recycleable waste is also treated at plants in Sungei Kadut, Jurong, Tuas and other areas.

To keep costs low, amenities at the Sarimbun park are kept to a minimum.

Located amid dense trees, it is not even powered up - firms rely on their own generators.

The area is served by one bus service. The nearest MRT stations are Kranji and Boon Lay, each a 20-minute drive away.

For food, workers have to go to Kranji or Jurong Point.

Said Mr Parry Yeo, founder of Morelastic Green, which recycles tyres: 'It's pretty far, but we have become used to it.'

Security is sometimes a problem, with firms having lost between $300 and $120,000 worth of equipment from break-ins, so companies now hire their own security guards and keep an eye out for each other.

However, they are willing to put up with the deprivations to keep their rents down.

Said Mr Yeo: 'We are very happy to be there. Anywhere else would be too costly.'

The twice-renewable three-year lease comes at 68 cents per sq m a month, or a low $8.16 per sq m a year.

For a typical 20,000sq m or 2ha plot, this works out to just over $163,000 in rent annually.

The rental rate was reduced this year to 55 cents per sq m a month to help the companies weather the economic crisis.

In comparison, rentals are twice as much, at $16.21 per sq m a year, at the JTC Corp-run Ecopark, a 19ha site beside the Tuas incinerator.

The Ecopark has three tenants which engage in higher value-added recycling activities, churning out products with better profit margins in the process.

Singapore's only fully automated waste-sorting plant is also located there.

For now, a park like Sarimbun can fulfil Singapore's recycling targets.

Given the land value on this tiny piece of land, finding a similar location would be difficult.

A spokesman from SembCorp Environmental Management, which will recycle construction and demolition waste, could only think of one other suitable spot.

'Possibly Jurong Island,' she said.