TDP 17 - A biological sequential reactive barrier (SEREBAR): Design, installation and performance at a former manufactured gas plant (FMGP) site in South West England (2008)

This Technology Demonstration Project Report describes the design, installation and performance of a biological, sequential reactive barrier (SEREBAR) at a former manufactured gas plant site.

Past activities at the site have resulted in elevated concentrations of organic compounds in soils and groundwater. The organic contaminants of concern are primarily Polycyclic Aromatic Hydrocarbons (PAHs), Benzene, Toluene, Ethylbenzene, Xylene (BTEXs), as well as other organic compounds (phenols and cresols). Based upon the human health and ecological risk assessment of the groundwater conducted for the study site, remediation works to address groundwater contamination were considered.

The selected remedial action consisted of the installation of a SEquential REactive BARrier (SEREBAR) whereby the priority pollutants are removed in situ by a combination of anaerobic/aerobic biodegradation with the added protective measure of a sorption process.

The SEREBAR project was a collaborative research project between five academic partners and two industrial partners. The main aim was to implement a remediation solution that effectively removes organic contaminants and cyanide, which in turn would act as a flagship within the UK for companies interested in sequential treatment trains within permeable reactive barrier (PRB) technology.

TDP 20 - Design and installation of a permeable reactive barrier to treat carbon disulphide contaminated groundwater

This Technology Demonstration Project Report describes the design, installation and performance of a permeable reactive barrier (PRB) to treat carbon disulphide (CS2) contaminated groundwater. This was the first application of zero-valent iron for the treatment of CS2 and one of the few full-scale PRB implementations to date in the UK.

Of primary concern was the presence of dense non-aqueous phase liquid (DNAPL) CS2 in the sand aquifer and residual CS2 in the unsaturated zone. A secondary concern was the presence of a small dissolved plume of CS2, carbon tetrachloride (CCl4) and the latter’s primary biodegradation product, chloroform (CHCl3), in the shallow sand aquifer.  The purpose of the PRB was to reduce the concentration of dissolved CS2 in the shallow groundwater to a concentration that is protective of the identified downgradient controlled water receptors, whilst ensuring that there are no significant effects on regional groundwater flow.

TDP 24 - Thermally enhanced soil vapour extraction to remediate the unsaturated zone at the Western Storage Area, Harwell

This Technology Demonstration Project Report describes the application of thermally enhanced soil vapour extraction (TESVE) to remediate the residual contamination within the unsaturated zone and zone of water table fluctuation at the Western Storage Area, Harwell. This is the first application of TESVE in the UK using in situ thermal desorption (ISTD) technology.

The primary aim of the project is to reduce the mass of volatile organic compounds (VOCs) in the source area unsaturated zone to the extent that it is economically feasible, resulting in a diminishing flux of mass to groundwater over time.

TDP24 - Thermally enhanced soil vapour extraction to remediate the unsaturated zone at the Western Storage Area, Harwell