Posted on May 6th, 2009
PROjEN solution to satisfying Buncefield Recommendations
PROjEN, a multi-disciplined Project Management Company from Northwich in Cheshire has demonstrated success in the practical interpretation and implementation of recommendations from the Buncefield Enquiry and the Environment Agency Containment Report. Independent tests have proven the design and construction methods used by PROjEN in the upgrading of fuel terminals on the South Coast will satisfy the essential requirements as detailed in both reports.
PROjEN were engaged by Greenergy Terminals Ltd to upgrade existing facilities at the Cattedown and Mayflower Terminals in Plymouth to almost double their existing capacity whilst providing improvements in reliability, efficiency and secondary containment. The investment will facilitate the roll-out of fuels to retail outlets in the South West. Greenergy and PROjEN have consulted with both the Health & Safety Executive (HSE) and Environment Agency (EA) during the planning of the works.
A new Containment Policy relating to the Containment of Bulk Hazardous Liquids at COMAH establishments has been developed and issued by the Authorities in the last 12 months to establish a consistent approach and the basis for enforcement action. The first phase of the policy applies to those COMAH establishments storing petroleum/other liquid fuels. The expectation for most new build bunds will be that they will be of concrete construction. However, for existing sites with earth/clay floor bunds (as found at many fuel storage terminals in the UK) factors which come into play include time constraints to effect any changes (due to operational issues) and the principles of proportionality and reducing risk to a level As Low As Reasonably Practicable (ALARP).
The fuel sector in particular has high potential for significant environmental impact and any establishment which has potential to cause a Major Accident To The Environment (MATTE) is required to implement all Containment Policy Control Measures necessary for preventing and mitigating MATTE. The failure of secondary and tertiary containment at Buncefield in 2005 contributed significantly to the failure to prevent MATTE. Individual site affordability should not be a factor in avoiding upgrade.
Containment Policy Control Measures include (but are not limited to);
- Above Ground Storage Tanks shall be bunded to provide secondary containment
- Bunds should be impermeable
- Bunds should have adequate corrosion resistance, strength and durability
- Bunds should have sufficient capacity to allow for tank failure and firewater management – normally the greater of 110% of the largest tank or 25% of all tanks within the bund
- Bunds should have no pipework that penetrates through the bund floor
With the above measures in mind, PROjEN undertook the upgrade works at Plymouth which included the demolition of some storage tanks and replacement with new tanks, installation of road tanker loading facilities, provision of blending facilities, improved control systems and improvements to the secondary containment bunds. The bund improvements proposed included replacement of the earth bund walls with walls of a concrete construction, a new floor to include an impermeable membrane liner plus layers of protective geotextile material and basalt rock gravel.
Following meetings with the HSE/EA it was agreed an independent test be carried out on the proposed design to demonstrate compliance with the Containment Policy, particularly with respect to bund integrity and resistance to fire. The liner itself has been used for many years and used extensively around the world on similar installations. However, no recorded test results for fire resistance were available and providing sufficient time to allow emergency services to act was a key element of the design.
Fire tests were performed by Chiltern International Fire Ltd on both the liner on its own and using the installation method as proposed by PROjEN. The test results concluded that the liner in isolation was not capable of withstanding a fuel fire. However, by employing the design as used at Plymouth the fire was contained for over 3 hours – before self extinguishing. It is clear that the combined use of basalt rock gravel limits the amount of oxygen available to the vapourising fuel and it only ignites once it has reached the surface of the stone, thus providing the necessary time for the fire services to act, should an incident similar to Buncefield occur.
PROjEN’s Managing Director, Martin Seabrook comments “PROjEN are extremely pleased to have been involved in proving this design complies with requirements as laid down by the various authorities. We would recommend the use of the liner and associated construction materials as a means of ensuring all other existing and similarly constructed sites meet the legislation compliance requirements in an easily installed and cost effective manner”