Case Studies

We are pleased to share some of the details of successful applications of remediation solutions, particularly where the project is complex or otherwise noteworthy, or where the techniques applied are innovative. New Case Studies will appear on the site from time to time. If you would like to receive these by e-mail as soon as published, or to obtain the full version of a case study report, please send an e-mail, stating your requirements and giving full address details to:

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Case Study No. 3 -

    Rochester RiversideGroundwater Remediation

The Site  

·       First Thames Gateway project, a flagship brownfield regeneration project.

 

·       Investigations indicated elevated concentrations of petroleum hydrocarbons originating from the former gas works.

 

·       The site is highly permeable with groundwater contamination (DNAPL and dissolved phase hydrocarbons) within the river terrace gravel and within the made ground at shallow depths.

 

·       Dissolved phase contamination of chalk aquifer.

 

·       The site is being redeveloped for residential and commercial end use.

 

The Solution  

·       Involves the application of several remediation technologies to address contamination:

 

o        Pulsed DNAPL recovery from deep boreholes;

o        Flow path management in parallel shallow trenches;

o        Chemical oxidation to remove dissolved phase contamination

 

·       Licensed by the Environment Agency under MPL, abstraction licence and discharge consent.  Asymptotic targets agreed with regulators.

 

 

The Results 

·       Regulatory closure for the flow path management and several boreholes.

 

·       Over 18,000 l of DNAPL tar recovered and approximately 2,200 kg of dissolved phase contamination. 

 

·       Significant reduction in risks posed to groundwater and human health.

 

·       Site works undertaken in conjunction with earthworks and other remediation contractors on a very busy site.

 

·       High profile project within the remediation industry, the Environment Agency and other regulators.

 

·       Recipient of the Brownfield Briefing Remediation Industry Awards Best Use of Combined Systems 2007.

 

·       On program to achieve closeout by end of 2008.