Environmental problem caused by the presence of Lindane in Sabiñanigo (Huesca)
Since 2009, Emgrisa has been involved in the development of diverse activities related to the presence of lindane in the municipality of Sabiñánigo. The origin of lindane was from the production of pesticides at a factory closed in 1992. Work first awarded to Emgrisa by the Ministry of Environment and since 2010 in collaboration with the Department of Environment of the Government of Aragón and recently with the Ebro Hydrographic Water Authority.
The presence of lindane in Sabiñánigo constitutes one of the biggest environmental problems in Spain. At present there are three lindane hot spots:
- The abandoned pesticide factory of Inquinosa.
- The old municipal Sardas landfill.
- The Bailín landfill.
Such is the problem with this compound that between the months of September and October of 2014, the use of tap water was forbidden in the towns and villages between Sabiñánigo and Zaragoza, nearly 130 kms along the route of the River Gállego. In March of 2015, there was another alert for lindane contamination.
The recent projects that Emgrisa has completed in Sabiñánigo are as follows:
- Hydrogeological monitoring of the Sardas landfill (since 2015).
- Evaluation of the presence of lindane in the River Gállego during the summer of 2014 as a consequence to the dismantling of the Bailín landfill.
- Removal of sediment impacted with lindane from the channel bed of a natural drainage ravine in Bailín (2014-2015)
- Study of alternatives and project to reroute surface runoff in the Bailin ravine (2016-2017)
Monitoring and control of the Sardas landfill for environmental risk
The Sardas landfill has more than 400,000 m3 for all types of domestic, industrial and construction waste and was in use for over 20 years. The waste was disposed directly onto the land without any prevention measures installed. Industrial waste included products derived from the manufacture of chlorine, lindane (g-HCH) and various isomers of HCH (Hexachlorocyclohexane) in the form of dust and free phase (DNAPL).
Lindane and several of the organochloride compounds present are considered as persistent organic pollutants (POP) and included in the Convention of Stockholm. The nature and volume of the pollutants present in the Sardas landfill, as well as the very close proximity of the River Gállego and the other sites in the Sabiñánigo municipality (Bailín landfill and the abandoned Inquinosa factory) constitutes one of the major environmental risks in Spain.
Since 2009, Emgrisa has completed the following environmental tasks in the Sardas landfill:
- Site investigation and characterization.
- Hydrogeological tests and modelling.
- Laboratory analyses and tests.
- Daily environmental control.
- Hydrogeological monitoring and quality control.
- Remedial actions.
The work completed by Emgrisa has two objectives:
One is to gain more knowledge of the situation and refine the Conceptual Site Model and the other is to perform small scale remedial activities to reduce the contamination.
In order to fulfill these two objectives we have three specialized technicians permanently on site performing the various tasks from environmental monitoring through to small scale remedial activities.
The work completed since the beginning of the project is as follows:
- Construction and installation of over 70 monitoring and pumping wells.
- Collection and analyses of many soil samples, sludge samples and leachate.
- Collection and analyses of groundwater samples.
- Hydrogeological pump tests including traceability tests.
- Laboratory treatment tests on contaminated soil.
- Other work completed by the permanent site staff since the beginning of the projects includes the removal of approximately 2000 litres of DNAPL.
- Weekly review with client on progress and on health & safety issues.
The environmental control of the Sardas landfill is done through monitoring of daily critical parameters and monthly sampling campaigns at defined key locations. Additionally, continuous improvement of security protocols and control guarantees the health & safety of workers and third parties.
The Sardas landfill environmental project is providing Emgrisa with increasing knowledge and experience on persistent organic pollutants (POP)