The pesticide lindane was widely produced globally during the second half of the 20th century. But due its toxicity, it has now been prohibited or restricted in most European countries. 

Bailín is one of three sites in Aragon – a province in north-eastern Spain – that has been heavily contaminated by lindane production. This has polluted both the local soil and groundwater. 

Cleaning up these contaminants across Bailín’s complex fractured geological landscape poses a significant and long-term challenge.  

Appointed in 2008 by the regional government under a €10 million EU-funded FEDER programme, our specialists are conducting the remediation of lindane-contaminated groundwater at the legacy landfill at Bailín-Aragon. 

To help us achieve this, we are actively collaborating with research institutions (Gaiker) and universities (Universidad Complutense de Madrid and Universidad Autónoma de Barcelona). 

Assessing groundwater contamination 

Our first task was to develop a conceptual site model (CSM). A critical stage of any remediation project, this presents a comprehensive picture of the site and identifies potential risks to the environment and human health.  

The CSM was also pivotal in helping the team select the best remediation technique to test and apply – including those that use nature-based solutions.  

Harnessing tools and technologies such as passive flux meters, groundwater modelling and passive soil gas surveys, we gained a deeper insight into the behaviour and migration of the contaminants. This enabled project engineers to target treatment areas more precisely. 

A significant part of this project was delivered using remote monitoring technology which allows us to capture real-time data from across the site. By limiting in-person visits, we’re not only protecting employees but also helping lower carbon emissions. 

Land contamination is a socially and politically delicate subject. But through sharing our results with stakeholders and the wider public, we have ensured that the local community is kept well informed. 

Designing an effective remediation strategy

Our ongoing work at Bailín has been instrumental in helping the client design an investigation and remediation strategy that can be rolled out to other sites and applied to different contaminants. 

Once complete, this project will significantly improve water quality at Bailín – protecting public health and restoring the environment for future generations.