No smoke without fire water: it’s time to close in on pollution containment
It’s a surprising fact that the most likely environmental damage caused by fire at an industrial site is not actually a result of the fire itself, but the water that is used to fight it. It’s not air pollution or even the combusting materials themselves that most often cause serious environmental harm in major industrial fires, but the huge quantities of fire water discharged in a very short time to get the fire under control.
In the early stages of a major industrial fire, thousands of litres of water are discharged into the environment every minute. The surface water runoff created will pick up the pollutants and contaminants of whatever burning or hazardous substances are present, and if a site is not fully contained, they will escape into the local environment. There is even the potential ‘worst case’ scenario of fire water and heavy rainfall combining to overwhelm a containment area.
When such events occur, the water can find routes to flow across a site in directions no-one had ever expected, let alone mapped, before ending up in a river or sewer. Such a pollution incident can lead to crippling costs to pay for the cleanup and to put right the environmental damage. Most companies believe that they are fully insured under their standard material damage liability policy, but could find they their insurance does not fully cover them for remediation costs required by the regulator.
Fire Water Runoff
The fire at the Jayplas plastics and paper recycling plant in Smethwick in June 2013 is memorable for having been started by a Chinese lantern. The fire was the largest ever dealt with by the West Midlands Fire Service which deployed over 200 firefighters and nearly 40 appliances to deal with the fire involving 100,000 tonnes of plastic recycling material. The incident serves as an example of the amount of water that can be used in a fire incident: in the first 12 hours of operations, 14 million litres of fire water were needed and water was pumped from the nearby Birmingham Canal.
Following a fire at another recycling plant in Kidderminster at around the same time, the Environment Agency was reported to be engaged in a clean-up operation to raise oxygen levels in the Staffordshire and Worcestershire canal. According to reports, the oxygen levels dropped as low as 1% and 200 fish died. Following a warehouse fire at Bilston in Derbyshire in 2011 the Canal and River Trust was involved in rescuing fish at a cost of £1,000 a day, although 100,000 fish died, according to the media reports.
Regulations and Guidance
Industrial, commercial or warehousing facilities that use or store hazardous or polluting substances need to take steps to ensure they do not escape into the environment. Pollution containment is critical for sites operating under the Control of Major Accidents and Hazards (COMAH) 2015 or Environmental Permitting (England and Wales) Regulations (EPR) 2010. It should also be integral to any compliant Environmental Management System (EMS) – or for those companies working to IS0 14001.
Revised COMAH Regulations came into force in June 2015 giving all sites 12 months to review their compliance. Sites that are vulnerable to flooding or pollution spills are strongly advised to review both their on-site protection and the risk assessment evidence they need to support it.
Even for sites where the substances stored are not hazardous in themselves, fire fighting water can still be a concern. As the above examples demonstrate, fires at waste handling and recycling sites have been a particular focus for concern in recent years.
Following the high-profile fires at waste handling premises, the Environment Agency issued revised Technical Guidance for sites storing combustible waste in 2015, instructing them to review their fire accident planning with a ‘must’ action to meet the standards.
WISH (The Waste Industry Safety and Health Forum) has also issued helpful industry guidance “Reducing Fire Risk and Waste Management Sites”. During 2014 the Environment Agency reported 10 serious water pollution incidents involving waste management activities, five of which were caused by fires and three by containment and control failures.
After the Buncefield disaster in 2005, the Health and Safety Executive found that protective bunding had many flaws that caused large volumes of fuel, foam and fire fighting water to leave the site.
The site’s last line of water pollution defence – so-called tertiary containment – was practically non-existent, amounting only to the sites surface drainage systems which were not designed to cope with any large-scale releases. In July 2010 five companies were fined a total of £9.5 million for their part in the Buncefield disaster.
The UK’s central industry guidance document CIRIA 736 Containment Systems for the Prevention of Pollution was significantly revised in 2014 in the light of lessons learned, particularly from the Buncefield disaster and sets out clear guidance on the steps to take for water pollution containment.
Sources and Pathways
Operators should have a thorough understanding of potential water pollution sources and pathways – especially where their site is located in a flood-prone area. Many firms are unknowingly risking water pollution incidents because they rely on inadequate containment systems, or because they do not know how flood water or surface water runoff will be directed on and off their site
Providing evidence of how surface water is discharging to the environment should be on the agenda of any company that is keen to act sustainably. As well as being environmentally unacceptable, inadequate water pollution containment could be very costly.
As government funding is cut back, environmental authorities are increasingly being forced to relinquish their advisory role and are enforcing regulations through prosecution. Furthermore, regulatory authorities are now clamping down with big fines and stricter expectations on organisations to provide proof of the measures they have taken to protect themselves and the surrounding environment. If they cannot provide such proof then they may be forced down the route of expensive remediation that might otherwise have been avoided.
The “Polluter Pays” principle allows for the recovery of costs needed to put the environment back to how it was before the incident. Incidents involving the regulator are unlikely to be fully covered under a company’s standard material damage liability policy.
Following a prosecution for a water pollution incident, fines can be significant. In the worst cases, a pollution conviction can even include the option of custodial sentences for company directors. Given the financial costs and the potential loss of reputation for any company, it’s clear that taking steps to avoid such a scenario is highly commercially advisable.
In another reference, CIRIA C736 gives details of a Huddersfield manufacturer and repackager of chemicals such as fungicides, insecticides and pharmaceutical products which suffered a fire in May 2010. According to the case study, approximately 5000 m2 of fire fighting water and 20 m2 of foam were applied to the site in the first five hours of the fighting the fire. The site’s tertiary containment system was not able to cope with the quantities of fire fighting water runoff and foam generated and consequently significant quantities escaped the site boundary into the River Colne.
The case study details how the company embarked on a number of improvements following the fire starting with surveying and tracing all site drainage to understand how fire fighting water is transported around the site during the incident and developed a plan for managing fire fighting water runoff from future incidents.
To provide water pollution containment, most companies begin by installing isolation valves in the outlets to surface water drainage to prevent flood or fire water escaping from the site and contain it until it can be safely removed and tankered away. In addition, bunds or physical barriers can be constructed, especially around hazardous areas, such as oil or chemical tanks to contain spills.
It’s important that valves are of the correct design. Often companies install a penstock, but the word ‘penstock’ represents many types of valves that do not all have the ability to drop seal low pressure flows fully; if a site is looking to contain pollution then the valve must contain the entire flow. Penstocks are closed by the force of the ‘head’ of water rising in the drain.
We recommend using drop seal valve technology which is the latest technological development and provides a watertight, failsafe solution that is already installed at more than 150 sites across the UK. The latest version is called the Hydro-Brake® Isolator pollution containment valve.
On more complex sites, operators will also still need to be sure that, even with valves installed, in the case of a fire incident, the surface water drainage won’t back up, overtop bunds and storage measures and flow out of the site into the surrounding environment.
CIRIA C736 recommends a full risk assessment based on the source-pathway-receptor model to aid in a holistic containment strategy based on the hazards of the site. Hydraulic modelling techniques are a valuable way of mapping the surface water pathways on and off a site, then test out and prove any valves, bunds or temporary storage measures that are then proposed. A solution can be designed and constructed in the safe knowledge that any potential incident will be fully-contained.
Waste and recycling operators interested in the Hydro-Brake® Isolator pollution containment valve or Water Pollution Management hydraulic modelling can book a free initial on-site assessment.
For more information, go to www.hydro-int.com