Remediation of Buried Beryllium Waste

Client / HAWK Contracts (on behalf of St. Modwens)
Site / Former Britannia Zinc Smelting Works, Avonmouth
Value / £275k
Timescale / 12 weeks

Summary

The enabling and remediation works for this development would disturb historically buried waste materials containing high concentrations of Beryllium, as well as the surrounding soils containing high concentrations of arsenic, lead and asbestos contamination.

All of these detected carcinogens posed acute and chronic risks to the health of contractors on site and surrounding land users, with Beryllium posing additional risks to the eyes and skin, and so specific management procedures and control measures were required for the works to be carried out safely.

Sanctus, being a Licensed Asbestos and Remediation Contractor, already had adaptable management systems and necessary experience for managing hazardous working environments and contaminated soil, and was appointed to carry out the specialist works. The works included:

  • Development and implementation of a Beryllium-specific health surveillance management system for remediation workers.
  • Beryllium and asbestos control measures including: designated working areas, decontamination facility, powered full-face masks and disposable suits, and far- and point-source dust suppression systems.
  • Personal and boundary air monitoring for respirable asbestos, beryllium and lead to monitor efficiency of control measures. On no occasion were concentrations detected that exceeded the limit of detection or HSE control limit for asbestos, or Workplace Exposure Limits (WEL) for beryllium or lead.
  • Temporary works design and supervision for carrying out deep excavations.
  • Construction of soil treatment area.
  • Delineation and excavation of 2,500m3 of buried waste and soil from 6no trenches identified by previous investigations.
  • Validation of trench sides and bases, and screened soils.
  • Segregation of waste materials (including metal drums, glass bottles, historic PPE, 2no metal storage boxes, and filter paper) and disposal at suitably licensed facilities.
  • Specialist laboratory analysis using a scanning electron microscope (SEM) to determine composition of unidentified materials segregated with the above waste. The SEM analysis and Sanctus research of smelting techniques identified the objects to be used graphite electrodes. Sanctus was then able to assign an EWC code and classify them as waste, before disposing of them at a suitably licensed facility.
  • Engineered placement of segregated soil back into remediation excavations.
  • Dewatering and treatment of groundwater.
  • Verification reporting.