杏吧原创

杏吧原创s and engineers play an essential role putting together colossal events like the Olympic games

A SINGLE great crested newt is all it would have taken to turn Kim Olliver鈥檚 life into a nightmare during the spring of 2007. Luckily, Bully Point Pond in east London contained nothing but the less endangered smooth newt. Fast-forward to 2012 and the pond has been enlarged and is now an area for spectators and athletes to chill out, away from the action of the games.

鈥淚f we had found great crested newts that day we would have had to apply for a licence to move them, the whole thing could have taken months or potentially years,鈥� delaying the development of the site, says Olliver, an ecologist at the London-based engineering firm Atkins, which has played a role in the development of the site since the beginning of its Olympic development. Instead, Olliver and her team relocated 3000 smooth newts to a local nature reserve 鈥� an exceptionally large number for such a small pond.

When the Olympics come to London in two years鈥� time, its organisers will not only be hoping to top the medal board, they will also be looking to impress the world with their green credentials. 鈥淭he main reason London won the bid to host the Olympic games was because we promised to put sustainability and environmental issues first,鈥� says Jerome Frost, head of design for the Olympic Delivery Authority (ODA), the government body set up to oversee the development.

聯45 hectares of wildlife habitat will be built, including 525 bird boxes and 150 bat boxes聰

So while trapping newts on your hands and knees in a sludgy pond may seem a world away from winning medals, scientists like Olliver are just as much part of the UK鈥檚 Olympic effort as the athletes. 杏吧原创s and engineers are involved in everything from cleaning up the contamination of the site to designing state-of-the-art venues with impeccable environmental credentials to modelling the geology of the site to determine how far down to dig the venues鈥� foundations.

聯4000 trees will be planted on the Olympic Park and Olympic Village sites聰

Neglected land

Since Victorian times the Lower Lea valley, the location of the Olympic site, has been a haven for ancient landfills and factories with dubious environmental credentials. The world鈥檚 first plastic factory opened nearby in 1866, while the UK鈥檚 first petrol refinery operated out of the site three decades later. 鈥淎s London became more and more civilised, all of the awful, foul-smelling industries and landfills moved out to the Lea valley,鈥� says Stuart Hayes, a hydrogeologist based at the Environment Agency in London.

Today, the Lower Lea valley is one of the most hard done by areas of the UK and contains some of London鈥檚 most contaminated land. The river Lea, which meanders through the valley until it meets the river Thames in the east end of London, used to be an industrial waterway and is still polluted today. The area is crying out for regeneration and the Olympic development has got the ball rolling by restoring the rivers and canals, and cleaning up the polluted land.

As part of the games鈥檚 legacy, every venue and site is designed so that they continue to have a function after the Olympic flame has passed to another nation. For example, part of Olliver鈥檚 job is to tempt birds and other wildlife to the site so that once the games are over, the site develops into a haven rich in biodiversity for local people to enjoy.

聯More than 16, 000 square metres of green roof 鈥� vegetation consisting of moss, wild flowers and other plants 鈥� to be installed on roofs across the Olympic Park聰

Before construction work could start, contamination of the 250 hectare site had to be cleaned up. Hayes advised the ODA on what types of contamination they were likely to encounter and, together with a team of geologists, devised a strategy to determine the extent of the pollution. Soil contaminated with petrol, oil, lead, tar, cyanide and arsenic from around the site was dug up and decontaminated in a makeshift 鈥渟oil hospital鈥� that was set up on site by , an environmental engineering firm based in Zwijndrecht, Belgium.

The cleaning process involved piling the soil onto concrete beds and feeding it with vegetable oil and dairy products. The concoction accelerates the breakdown of the contaminants by encouraging the bacteria in the soil to breed, says Hayes. The soil hospital also boasted five washing machines which shook oil, cyanide and lead free from the soil. 鈥淚n total, we鈥檝e cleaned nearly 2 million tonnes of contaminated soil, which makes it the UK鈥檚 largest ever soil-washing operation,鈥� says Saphina Sharif, an Atkins engineer in charge of the clean-up. The cleaned soil was then used to landscape the Olympic Park. Any soil that was too contaminated to be cleaned was sent to a specially licensed landfill.

One area that Hayes was particularly worried about was the land surrounding a chemical factory that was in use until the London Development Agency bought the land for the Olympic development. Once London-based engineering firm, WSP Group, started to investigate the area, it quickly became clear that things were even worse than expected. Chlorinated solvents had leaked into the groundwater, producing a plume of carcinogenic vinyl chloride. Some of the heavier chemicals had sunk to a depth of 40 metres and entered the bedrock below.

聯90 million litres of contaminated groundwater cleaned聰

The factory has since been removed but unlike the rest of the Olympic Park, which was cleaned up before building work started, the remediation of the chemical-factory site, which includes cleaning the soil with powerful chemicals, will continue right up until the games begin and afterwards too.

While building on polluted land is hard work, it is sometimes unavoidable. In an effort to regenerate this part of London, the law states that 80 per cent of all new development in the Thames Gateway, a 65-kilometre-stretch of land along the river Thames, must occur on old industrial, 鈥渂rownfield鈥� land.

Another aspect to consider before Olympic construction could get under way was how changing the landscape could alter the hydrology of the region. Building work affects how the area will flood because it disrupts natural overland flood routes connecting high and low ground. This has exacerbated the risk of floods in some parts of the Olympic site. To make matters worse, the spring tides are predicted to be particularly high during the games. 鈥淐all it sod鈥檚 law,鈥� says Mike Vaughan, an engineer with Atkins.

聯2 million tonnes of contaminated soil cleaned for reuse聰

To predict how construction at the site would change the pattern of potential flooding in the region, Vaughan developed a hydrological model. It also allowed him to model engineering solutions to the problem. One solution was to build an area of wetland marsh on the banks of the river, upstream of the stadium, that can cope with a rise in water level of up to 6.5 metres before it spills into the surrounding land. Vaughan also constructed a culvert 鈥� a giant, underground pipe 鈥� that will drain water from an area now at risk from flooding and dump it further downstream, reducing the flood risk to 4000 properties in nearby Canning Town.

聯30,000 tonnes of silt, gravel and other materials dredged from the rivers聰

Eco-friendly design

Tucked just inland of the wetland area is the velodrome, widely considered to be one of the most eco-friendly buildings in the Olympic Park. 鈥淭here is something beautiful about a building that is as efficient as a bicycle,鈥� says Andrew Weir at Expedition Engineering, the London-based company that was involved in designing it. 鈥淲e wanted to create a building that doesn鈥檛 have any fat on it, like a Tour de France cyclist.鈥�

The velodrome鈥檚 roof, which consists of intertwined steel cables, weighs roughly half that of any other velodrome. Although the building will be heated to 26 掳C during events 鈥� thinning the air and making the cyclists go marginally faster 鈥� it is heavily insulated, reducing the need to use fossil fuels to maintain the temperature.

The track is made from baltic pine harvested from sustainably managed forests and windows run the length of the roof, bathing the track in natural light. 鈥淔or around 90 per cent of the day lights will be unnecessary,鈥� says Weir. Prioritising sustainability and function as well as aesthetics when designing new buildings is only going to become more common, says Weir. 鈥淲ith the government鈥檚 demands for energy efficient buildings becoming tighter and tighter, in 10 years鈥� time anyone who hasn鈥檛 jumped on this bandwagon will be extinct,鈥� he says.

The ODA has set stringent sustainability goals for its contractors: reuse or recycle 90 per cent of all construction waste, deliver 60 per cent of their construction materials to the site by rail or barge and ensure all of the wood bought has been certified by the Forest Stewardship Council, an NGO that tracks timber to ensure that it is sustainably sourced. It is Christian Bonard鈥檚 task to make sure that contractors do not cut corners 鈥� and to catch them if they do. Having worked as an environment manager on the construction of Heathrow Airport鈥檚 Terminal 5, he is now employed by American firm CH2M Hill and in charge of a team of environmental consultants on the Olympic site. A key duty is to make sure that the wider workforce 鈥� not just the managers 鈥� understand the rules. 鈥淚t is all about instilling a sense of thoughtfulness in people to prevent things from going wrong in the first place,鈥� says Bonard.

聯20 per cent of energy used in the park will come from renewable sources聰

He and his team scour the site once a fortnight for signs of environmental malpractice, such as a generator leaking oil onto the ground. They take a photo of the problem before compiling a report and asking the contractor to make sure it doesn鈥檛 happen again. Bonard is also responsible for ensuring that levels of dust do not become dangerously high. There are eight dust monitors on site that send him and his team a text when concentrations of tiny airborne particles rise above a critical threshold. 鈥淲hen you get that text, you get out there, figure out what鈥檚 causing the problem and get the contractor to sort it out,鈥� says Bonard.

聯100 per cent of timber is Forest Stewardship Certified聰

Bonard also makes sure that when one company comes up with a good solution to an environmental problem, other contractors get to hear about it. For example, drip trays 鈥� metal trays placed beneath machinery to prevent oil from dripping onto the ground 鈥� have been all but phased out on site. 鈥淚 absolutely hate drip trays because as soon as it rains, the tray floods and spills its contents onto the soil,鈥� says Bonard. When Morrison, a contractor on site, started using a more environmentally friendly alternative known as a 鈥減lant nappy鈥�, he spread the word. When oil drips onto the plant nappy, it passes through a hydrophobic filter into its base, where it binds to a sponge. Rain water can鈥檛 penetrate the filter, so it spills out of the sides of the nappy and onto the ground.

In situations like this, being able to break complex information down into bite-sized chunks is critical to get the message across, says Bonard. You also need to be willing to fight your own corner. 鈥淵ou鈥檝e got to make sure that people put the environment first, even when they鈥檝e got other things on their plate,鈥� he says.