In November 2019 HFL Consulting was acquired by SLR, a global leader in environmental and advisory solutions.

SLR has a team of over 1800 professionals delivering advice and support from a network of offices across Europe, Asia-Pacific, Africa, Canada, the USA and Latin America. Our expanded service offering means we can provide a unique blend of leadership, management, consulting, engineering and training services to businesses of all sizes across the process and allied industries. We can draw on many more ‘in house’ skills and services, including process, civil and structural engineering, environmental permitting and compliance, air quality, flood risk, ecology, acoustics and wastewater treatment.

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The API manufacturing facility at Sandycroft, North Wales, was owned and operated by Euticals Limited, a UK subsidiary of a privately owned Italian API manufacturing company controlled by private financial investors. In July 2013, the UK business went into voluntary liquidation after running out of funds to re-start the plant following the issuance of two prohibition notices for COMAH, which were imposed by the Health & Safety Executive in November 2012.  The notices related to a recent serious accident, and the discovery of significant quantities of isosorbide dinitrate (classified as potentially explosive).  

Because of the sudden winding up of the business, the site was unexpectedly abandoned, leaving responsibility for what had been an active chemical manufacturing facility to Flintshire County Council, who were left with the problem of clearing the site to make it safe and ready for sale. As part of a multi-agency effort involving the Council, the Health and Safety Executive and Natural Resources Wales, HFL Consulting provided specialist technical support to help plan and manage the decontamination and clean-up work.  This process brought the site from a contained emergency state to a safe and stable condition.

The site had been left in disarray, with a range of substances in bulk storages and mobile containers, and in processing equipment on plant, all classified as dangerous under the COMAH Regulations. However, the substantial quantities of Isosorbide Dinitrate (ISDN), some of which was contaminated with other materials, presented by far the biggest problem. ISDN is used in treatments for patients with the heart condition, Angina but it is also a potentially explosive material, named in the Explosives Regulations 2005 and sensitive to temperature and impact.

The Challenge

A multi-agency effort to make the site safe

The range of substances left on site included those classified as toxic, explosive, flammable, corrosive and dangerous to the environment. The situation was further complicated because in addition to materials being present in bulk storage tanks and mobile containers, ISDN and other dangerous substances were left, part-processed, in equipment on plant but without the essential production records and certificates of analysis needed to determine the status of these materials. The former management team was also unavailable to give assistance, and other records for the site were scant and those that remained could not be relied on.

HFL Consulting’s team would need to help the Council understand the hazards and risks present, and help develop a strategy for removal of materials to make the site safe.

Managing the removal of hazardous substances

The Solution

  • 01

Providing technical expertise, a strategy and management support

By providing process safety engineering professionals supported by consultants with operational experience, HFL Consulting could advise the Council on relevant regulations, hazards and risks, and develop a strategy and programme of work for safe and efficient removal of all stored and in-process hazardous substances. The support provided included search and selection of suitably competent contractors to perform the cleanout and dismantling of plant and equipment containing explosive materials, management of those activities, and regular reporting to key stakeholders, including the Health and Safety Executive, Natural Resources Wales and the emergency services through the Emergency Command Structure.

Key Services

Regulatory Compliance

Requirements for handling and disposal of hazardous materials

Working as specialist advisers to Flintshire County Council, HFL Consulting provided technical support and guidance on disposal routes for the hazardous and explosive substances on site and identified competent contractors to remove the materials.

Process Safety Management Systems

Safe systems of work and planning

Operating on an abandoned site with unknown inventories of in-process materials and an absence of essential documentation required implementation of hybrid systems to manage access to plant, production and approval of method statements and risk assessments, and planning, management and supervision of work activities, all with minimum manning levels appropriate for the attendant risks

Risk Assessments

Hazard identification and risk assessment

HFL Consulting’s team of engineers and consultants developed a detailed inventory of raw materials, in-process materials and finished products, and assessed the risks to onsite and offsite personnel, based on the proposed processing, clean-out and disposal operations. This process was exacerbated by the presence of explosive materials, and the absence of any site waste water treatment facilities.
Key to this work was the engagement of and briefings to stakeholders, including the Council, regulatory bodies and the emergency services.

Safety Engineering

Management and supervision

Having identified and selected suitably competent contractors to dispose of the hazardous materials, and perform cleanout, dismantling and proving to render the facility free from explosive hazards, HFL Consulting provided ongoing site management and supervision to help the Council comply with its obligations as duty holder for the site.
Activities included controlling access to plant and equipment, approval of method statements and risk assessments, and completion of essential documentation to confirm that the site was free of any explosive hazard.

The Results

Over a period of 18 months, the HFL Consulting specialist team provided:

  • Technical support to the Council to assess site conditions
  • Safe systems of work for protection of people on and off site and the environment
  • A plan for timely removal of materials in bulk storage facilities and mobile containers
  • A strategy for emptying, cleaning and decontaminating process plant and equipment
  • A UK wide search for companies with competency to dispose of the explosive ISDN
  • A time-bound plan for safe cleaning and decontaminating process equipment
  • Day-to-day management and supervision of the contractor disposing of the ISDN
  • Day to day management and supervision of other work activities required to maintain safe conditions for all personnel in attendance
  • Management of aqueous waste streams for which there was no discharge consent
  • Updates and briefings for the Council and the Regulators at all stages
  • Briefings to the Emergency Command Structure as required
  • Project documentation, showing the site certified free from explosive hazard
  1. 01
    Developed a strategy and plan for decontamination
  2. 02
    Identified competent contractors to remove the range of hazardous materials present, including substantial quantities of ISDN in mobile containers and processing equipment
  3. 03
    Managed day-to-day activities associated with removal of hazardous materials from site
  4. 04
    Provided an essential link between the Council and other key stakeholders, including the Emergency Command Structure

Following the sudden and unexpected closure of the site, Flintshire County Council was landed with the unenviable task of making it safe. The previous occupants had left large quantities of hazardous materials there, which posed a considerable risk to the local area. Nowhere else in the UK had an upper tier COMAH site been abandoned in this way; this was unchartered territory and a major problem for the Council and emergency services.
Recognising the difficulty of the job in hand, HFL Consulting were engaged to assess the hazards and risks, provide essential technical guidance, identify competent contractors capable of removing the materials, and to plan and manage the clean-up work. We are pleased to report that all went well and without incident – a job well done under extremely difficult circumstances.

Director, HFL Consulting Limited

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