Ramboll Environ developed an innovative, sustainable and economically beneficial approach to addressing the impact of metal contamination on river sediments in the River Nent in Cumbria.
Our experts assessed the chemical and physical composition of heavy metal sediments (predominantly lead and zinc) impacting the river as a result of historical mine workings around Nenthead. After evaluating treatment, re-use and excavation and disposal options, we used a simple but effective bankside sampling method that saved our client approximately £125,000 in hazardous waste landfill tipping fees and a further £100,000 by avoiding the requirement for virgin construction materials.
Contaminated sediments not only affected the condition and habitat quality of the river, but the metals were also carried downstream, impacting the status of other waterbodies within the Tyne catchment. Our team met the objectives of the Coal Authority and Environment Agency to reduce contaminant loading to the river and improve downstream water quality in a sustainable and cost-effective manner, through careful analysis and forward thinking.