The big waste management firms are prone to blaming cowboy operators for the industry's poor reputation. In fact, a close reading of the Agency's new OPRA database points to an extremely mixed picture on operator performance.
Performance scores under OPRA reflect the extent of non-compliance against site licence conditions. Scores range from zero for full compliance to more than 100 in two cases. Inspectors add 15 points for each emergency situation, and a further three to nine points for each enforcement notice, depending on severity (ENDS Report 291, pp 43-44 ). Scores are assessed every three months, and averaged over the previous year.
The system was designed to assist the Agency in allocating inspection resources where they are most needed. Under a modified version of the waste OPRA scheme, operators will also soon face fees and charges which reflect the inspection effort to be applied (ENDS Report 327, p 47 ). OPRA also assigns scores to reflect the intrinsic hazards posed by a site, but these are not the focus of this article.
The waste OPRA database, which can now be downloaded from the Agency's web site, includes 921 landfills licensed to take biodegradable or hazardous waste. Not all of them are operational. Indeed, the evidence suggests that recently closed sites can cause major compliance headaches relating to leachate and odour problems.
Nearly a third of the 921 sites had a clean record, scoring zero points over the year in question - October 2001 to September 2002. The overwhelming majority - 83% - scored no more than 10 points.
However, several dozen sites scored 20 points or more. The table identifies these worst performers.
One surprise finding is that 25 of the worst performers - nearly a third of the list - have been identified by the Agency as having a certified environmental management system.
Notable by its absence from the list is Cory Environmental, one important landfill operator which appears to have enjoyed a good compliance record. Cleanaway, Onyx and Viridor also come out looking pretty good, with only one or two sites apiece among the poorest performers.
Waste Recycling Group, by contrast, has 15 sites on the list, Biffa has seven and Sita six.
Following numerous acquisitions and mergers, WRG is now the largest landfill business in the UK, with 62 sites in operation. But size alone does not explain WRG's poor OPRA scores. The company even has three sites among the worst ten.
Two of the sites, in north Lincolnshire, were acquired in 2001 when WRG bought Integrated Waste Management, formerly known as Humberside Wastewise, the local authority waste disposal company.
Winterton, which began co-disposal operations in 1982, has - by some distance - the worst performance score of any biodegradable waste landfill in England and Wales. WRG's Immingham site ranks third.
Despite having several other sites with poor scores, WRG claims that it has "a good overall compliance record and is fully committed to the goal of 100% compliance in accordance with site licence conditions." Both Winterton and Immingham now have certified environmental management systems.
Leachate and odour
Excessive leachate levels are a problem for most of the sites with the highest scores, and many of these have also attracted complaints about odour. At Winterton, leachate has seeped from the older "dilute and disperse" phase into the contained section over the last three years. Levels have reached 8.5 metres - more than four times the limit permitted by the site licence.
WRG "inherited a leachate management plan that didn't work," according to the Agency. A reverse osmosis treatment plant installed in the mid-1990s proved unreliable, and leachate had to be tankered off site for treatment. Both WRG and its predecessor "struggled" to control leachate levels, the Agency says.
In January 2002, the Agency served four enforcement notices to reduce leachate levels and address other leachate-related issues at Winterton. It took six months for the company to comply. During this time, in accordance with the OPRA methodology, performance scores recorded by the Agency at inspections are tripled.
WRG is designing a new treatment facility that will allow treated leachate to be discharged to sewer under a trade effluent consent. Small batches are now being treated and discharged using the existing plant, in addition to tankering.
The Winterton site also had problems with landfill gas migrating towards the village of Winteringham. This caused "severe crop damage" in neighbouring fields. Flare stacks and power generation plant have since been installed and emissions have been reduced to safer levels.
However, additional extraction wells had to be installed recently after gas levels increased along the site's northern boundary.
There have also been problems with daily cover. This is attributed by the Agency to a local shortage of suitable material caused by the large number of sites in the area which are exempt from waste management licensing.
Excessive leachate levels have also been the principal problem at Immingham which, like Winterton, is partly uncontained. There have also been problems with surface water drainage. The site is supposed to have a drain running around the perimeter, but in places the gap between the landfill and the perimeter fence is too narrow to accommodate it. Monitoring data have also been incomplete on occasions.
A third WRG landfill, Llanddulas in North Wales, has the ninth worst score. Acquired from Hanson in January 2001, the site is regulated under two licences, each with its own OPRA score. One covers a dilute and disperse phase which closed in the early 1990s as well as part of the operational area.
The other licence at Llanddulas covers a fully contained phase which closed roughly one year ago. Problems with excess leachate in this part of the site have earned it a place in the Agency's top ten.
A notice served last August required WRG to reduce leachate levels within a month, but this has still not been achieved. After reaching a peak about two years ago, the number of complaints has dropped off, and WRG has invested over £1 million in a treatment plant and other measures.
Agency inspectors sympathise with WRG's position - that the sites with serious problems were inherited from other operators. "It's ironic that a high performance score can be a reflection of proactive management," remarked one.
Shock for Shanks...
Another leading landfill business, Shanks, has two sites with very poor scores - Rossett in mid-Wales and Stewartby in Bedfordshire. These rank second and fourth, respectively, in the national league table.
The Rossett co-disposal site, near Wrexham, was acquired in 1999 when Shanks bought rival waste firm Caird. Its planning consent will expire in 2005.
Like WRG's poorest performers, the older part of the site is unlined. Three enforcement notices were served between February and May 2002 to bring leachate levels into compliance. This was achieved by June.
A fourth notice was issued in October requiring Shanks to address landfill gas leaks. Levels in the ground outside the boundary are currently being monitored daily. The Agency is still assessing a risk assessment provided by Shanks to decide whether it has complied with the notice.
In the case of Stewartby, Shanks cannot use the argument that it inherited the problems from someone else. The site is one of several old clay brick pits acquired from London Brick in the mid-1980s.
Leachate levels have been "significantly" too high, says the Agency, but have been contained by tankering. However, Shanks believes that a recently installed leachate treatment plant will bring the site's score down significantly. There have also been odour problems caused by landfill gas.
The site only has a couple of years left to run, and faces continuing pressure from residents for it to close. But more tipping is needed, says the Agency, to contour the face and ensure long-term environmental protection.
A thorough audit a few years ago flagged up a number of deficiencies in the site licence which, the Agency says, had held it back from taking enforcement action. A revised licence was issued a few weeks ago.
Shanks said it was surprised by the scores for Rossett and Stewartby and regards them as "exceptions". The company's average score without them would be around 10, it pointed out.
...and for Sita
Sita has been having a troubled year, with four prosecutions for landfill offences as well as enforcement notices relating to leachate management at six of its landfills in Lancashire (ENDS Report 335, pp 55-56 ).
Sita also runs one of the top ten problem sites, according to the OPRA database. Its Brenkley landfill, near Newcastle, is a former opencast coal mine. The dilute-and-disperse site covers a small area but, unusually, runs to a depth of some 50 metres.
Opened in 1991, it is due to close in the next few weeks. Its previous operator was Northumbrian Environmental Management, part of the Northumbrian Water group which was taken over by Sita's French parent company in the 1990s.
An enforcement notice was issued in June 2001 requiring Sita to produce an action plan for reducing leachate levels. Leachate had contaminated groundwater outside the site.
Sita installed 11 deep wells but there was no improvement. The licence stipulated that levels should not exceed one metre, but in two wells the levels reached almost 20 metres. Seven wells broke up under the pressure.
The Brenkley site has also suffered gas problems. These have been exacerbated by the fact that the landfill is in effect a single cell, with new layers being completed every few months. This makes it difficult to install extraction equipment. One half of the site is now capped and fitted with extraction plant and a gas flare. The same will be done in the other half later this year after the site closes.
Sita argues that Brenkley deserves a lower performance score, and that the Agency's north-east region interprets the OPRA scoring methodology differently from other regions. The company says that most regions accept that, when a remedial plan has been agreed, a site's non-compliance score can be downgraded "providing the plan was being complied with."
However, site inspector Tony Farthing says that Sita has yet to achieve full compliance with the plan. Moreover, if Brenkley's non-compliance scores were downgraded its total score would still be around 50, keeping it among the worst 20 or so sites in England and Wales.
Sita is not the only operator to complain that the OPRA system is interpreted inconsistently across the regions.
"There is a lot of inconsistency between our own audit results and the OPRA scores," says Biffa's David Savory. He also gives the recent example of a site where the OPRA score increased "dramatically" when a new inspector took over.
Operators, he says, should be allowed to respond to the scores, perhaps by means of a link on the Agency's database to their own web sites. This is something the Agency has already agreed to on its Pollution Inventory web site.
The fact that the scores are a "snapshot in time" is highlighted by many of the major operators. Several years' data might give a fairer picture of performance, they argue. "If you've got a problem or potential problem and are proactive with the Agency you can invite more inspections and be penalised as a result," said Shanks' spokesman John Shaughnessy. "But it will be increasingly useful over time."
Nevertheless, the major landfill operators are supportive of the OPRA scoring system - not least because of its link to risk-based regulation and the prospect of lower licence fees and inspection rates as site performance improves. Sita, for example, has modified its own compliance audit procedures to reflect the OPRA methodology.
Some also welcome the public availability of the data, providing greater transparency on company performance.
Biffa welcomes OPRA as an incentive to improve performance across the industry. "There are issues about how it is used, and it comes with the health warning necessary for any system that produces a magic number," says director Peter Jones. "But if we can get common standards across the regions it's got to be good news."
A future development, said Mr Jones, could be to link OPRA scores for waste sites to the waste industry performance indicators issued by the Green Alliance in 2001 (ENDS Report 323, p 18 ). The indicators have been endorsed by most of the major players, and several have used them in corporate environmental reports.