Case Study

PROJECT

Falmouth Harbour

Client: Land and Water Services Ltd

Location: Waste Treatment Centre, Wheal Jane, Truro, Cornwall

Contract Value: £86,500

Bio-accelerator – Rapid bioremediation  of hydrocarbons.
Cementex – Guaranteed stabilization of  heavy metals and phytotoxic contaminants.

 

The Falmouth Cruise Project comprised dredging works to create a deeper and straighter new navigation channel and to deepen the water berth along Queens and Northern Wharves.

Disposal of dredged material at sea was constrained by the local oyster and mussel beds. Dunton Environmental were able to provide treatment and dewatering of 2,500m3 of contaminated dredging spoil at our fixed treatment centre to achieve beneficial land re-use.

THE CHALLENGE

  • Land and Water were undertaking maintenance and capital dredging works to improve navigation and cruise facilities at Falmouth Docks, Cornwall. The main purpose was to facilitate sustained long-term growth of Falmouth’s cruise business.
  • CEFAS grab sample analysis indicated the finer fraction was contaminated with petroleum hydrocarbons and not suitable for disposal at sea due to local oyster and mussel beds.
  • Options available for disposal on land were limited as the dredged material was classified as hazardous waste under the Waste Framework Directive. The high moisture content further prohibited landfill disposal.

OUR SOLUTION

  • Dunton Environmental was able to provide a sustainable solution to landfill disposal at our fixed waste treatment centre located at Wheal Jane, Truro, Cornwall.
  • In order to service the UK and Ireland’s marine industry, Dunton has developed a unique solution that combines:
    • Dewatering techniques by applying our Cementex ™ product.
    • Separation of size fractions.
    • Destruction of contaminants of concern using our in-house Bio-Accelerator ™ and Regener8-19 ™ product range.
  • The treated material was then re-used in the restoration of the former quarry landfill at Wheal Jane.
Falmouth Harbour

Land & Water Group are the UK’s leading dredging company and operate the largest fleet of specialist long reach excavators and floating plant in the UK.

The Results –

  • Successful decontamination and stabilisation of circa. 2,500m3 hydrocarbon impacted dredging spoil.
  • Treatment diverted 100% of contaminated dredging spoil from hazardous landfill.
  • Provided beneficial re-use of treated material in accordance with DEFRA’s developing strategy for managing contaminated marine sediments.
  • Compliance analysis approved by the Environment Agency and Wheal Jane Ltd.
  • Project completed on budget and within the agreed programme.
  • Significant reduction in Clients costs over traditional disposal methods.
Falmouth Harbour

“We found Dunton to be a professional and competent subcontractor who performed to programme throughout, adhered to health & safety requirements and provided an excellent service. We were very satisfied.”

Tim Smith
Quantity Surveyor
SpellerMetcalfe