This summer was the second summer season, and the 4th stage of restoration capping at this Wexford County Council landfill during which Rowe Environmental provided capping construction quality assurance services.

The start of the works in June 2007 coincided with the uniqely heavy rainfall exprienced throughout the region that month. Although clay capping proceeded in between rain storms, problems arose with clay compaction due to the very waterlogged conditions on the landfill.

Civil Engineering Contractor Roadbridge used every opportunity to work whenever the site dried out in between rain showers, and the project was remarkable for not being not seriously delayed. This was despite the need for additional harrowing and recompaction of the clay over much of the site, in order to reduce the water content to acceptable levels, and the un-programmed addition of extra soils reinforcement to steep slopes within the restoration area.

The final stage of restoration capping at Killurin is programmed for next year when the recycling facilities and replacement residual waste landfill at the Council’s new Holmestown Landfill will be operational, and the Killurin Landfill closed.

The restoration capping works we completed this year
were similar to the Stage 3 of restoration which took place
through the summer of 2006.
Click on the image below to view
the Landfill Restoration slideshow for 2006:

This is a question for our expert visitors.

The answer is: “Leakage Detection Layers”. We have quoted some text from a US landfill lining systems report.

“The double-composite liner system, …, consists of a primary liner overlaying a secondary liner with a leak detection layer between the two liners. Both the primary and secondary liners have two low permeable components. The leak detection layer is a layer between the two liners. The purpose of the leak detection layer is monitor the performance of the upper liner and allow appropriate action to be taken when leachate is found in this layer. This liner system has a leachate collection system directly above the primary liner.”

Just why the idea never took off in Europe is the next question. It has been suggested to your BlogMaster that the presence of the leak detection layer introduces an additional weakness, and this is probably the reason why it is disliked outside the US. After all, if the leak detection layer becomes contaminated the leachate in it might find a hole anywhere across the base to escape through due to the ability for it to flow through the detection layer material itself.

Also the theory has it that to spend equal money due to the cost of the detection layer, on Landfill CQA is a much better investment, after all the landfill owner will be monitoring outside the landfill for any escape of leachate, in any case, as a matter of good practice, so the leakage detection layer isn’t essential to detect any leak.

Continue to use the “comment” link below, and tell us what you think about the cross-atlantic differences in approach here. We would be delighted to see you views.

Landfills traditionally have a reputation as unpleasant places, but many modern landfills are shaking up that image to the extent that even pre-school children have dropped in for a tour. 

You will find that at the landfills now, the standard of care for the environment is high. The owners are not allowed to keep the site open unless they have the skills and resources to prevent damage to the environment around the landfill site. None of he dirty water must leave the site unless it is treated, and landfill gas must be carefully controlled and used if possible for power generation and held safely from any risk of explosion, or fire. The landfills have been tidied up, and miraculously the litter which once could be seen around them has gone, and trees have been planted as screens.

So what has happened? Well the owners have taken on-board the need for improved environmental performance, and they have now realised that if they want another landfill when this one is full they will have to be a good neighbour. So, the best of them have taken the idea of good neighbourliness a bit further and added a training and educational resource centre to their site, for children and students. 

Every year each student intake will visit and be given the lessons that you really cannot throw anything away and just forget it. If you do, there will be bad effects on the environment from the rotting of these materials in such huge quantities which just grow every year, and need ever more cash to be thrown at preventing damage to the environment. So, by learning about waste in these centres the visitors will go away to take some responsibility for reducing the waste they produce. 

The visits also provide a forum to demonstrate the seriousness of the waste problem and the immense effort and investment needed to resolve it. The landfill resource centres all without exception provide a very clear message to their visitors that each must reduce their waste, engage in recycling and encourage their friends and relatives to do so too. 

In addition to the ordinary people which visit the many landfill site environmental educational centres, they are popular with politicians and experts who attend to give specialist presentations to local residents on particular nature and conservation topics of interest. For instance, the visitors from abroad are especially interested in the state of the art techniques used to control landfill gas and leachate - techniques which make these landfills among the most advanced in the world - and they often are considering building similar landfills in their countries. 

It is very rewarding to the resource centre site staff to see all generations in their centre and so willing to get involved at the growing number of these centres where the resources available are usually completely free, and know that they provide information in so many green and environmentally relevant topics.

While the work goes on within the educational centre at each site, the visitors also can observe site practice. This visibility to all helps give the residents of the neighbourhood the reassurance that any lapses in the environmental protection provided by the operator would be seen by the visitors straight away.

If standards ever dropped on these sites, it would be seen by the visitors and in no time at any failings would be seen, complained about, and put right. Without any doubt this is better than the old landfills which were hidden from public view. 

So, the new breed of landfill site visitor centres, usually funded by a combination of site owner, local source, and charities, are a great but unlikely success story.

If you want to see the type of educational resource which pupils are using to inspire their envionmental projects at places like these centres visit The Environment Pack web site here.