Great to see ITOO featured in the June edition of COVER Magazine. Head of Environmental, James Brice talks about the recent Earth Tremors felt in Johannesburg and further afield.

Here’s what he had to say…

The recent earth tremors felt in the Highveld might have come and gone, but their effects could be long-lasting.

The recent earth tremors felt in the Highveld might have come and gone, but their effects could be long-lasting.

According to the US Geological Survey (USGS), the epicenter of the latest tremor on the 3rd April 2017 was 8km from Stilfontein in the North West. Initial measurements recorded at a magnitude of 5.2, at a depth of about 5km. records people’s comments after tremors and earthquakes, and some of it makes entertaining but scary reading. “Sandton – tea spilt, stuff fell off cupboards. Polokwane – We sat and watched TV, and the next moment everything began to shake. The medals against the wall was shaking, the roof was shaking, our TV was shaking. Plettenberg bay – My husband and I felt a light shaking @ 08:50. Our neighbour also felt it. Mbabane – Vibrating bed. I thought wait a min. The manual didn’t say it had these perks. Cape Town – I was sitting watching TV eve. Late 2 April. I had no idea what time it was. I felt a faint vibration – thought it could be an airplane as they sometimes pass quite close before landing depending on the strength and direction of the wind. Also no wind at the time.”

What is interesting from these comments are:

They were felt countrywide. Literally millions of buildings, factories, filling stations, pipelines, etc. were all rattled, all across the country. Comments were recorded as far as Harare.

No damage was reported. In the August 2014 quake in Orkney (magnitude 5.3), someone in Pretoria reported: “Was at the office. Building structure could be felt flexing. Had two tremors with the second one more pronounced. Quite alarming. Multi-storey building, was checked by structural engineer, no structural damage.” While one fatality, 400 damaged buildings and 38 injuries were reported closer to the epicentre, the rest of the country took comfort in the fact that no damage was visible.
The problem is that we are not aware of anybody making inspections of their belowground infrastructure.

“From an environmental insurance point of view, the smaller the tremor, the bigger the risk,” says James Brice, head of environment at ITOO Special Risks “because nobody thinks anything has been damaged.”

Research has found that between 1907 and 1950 about 700 tremors were recorded in the Johannesburg area alone. Gold mining has further amplified the number and magnitude of seismic events. In the last 5 years alone, South Africa has been rattled by 34 events reported by people all over country. According to research, only 7.5% of earthquake related losses were covered by insurance.

It goes without saying that the stresses and forces that can be put on underground tanks and pipes during a seismic event, earth tremor or earthquake have the potential to cause extensive damage, says Sam Preece, Contamination Geologist and Environmental Risk Consultant at EBS Advisory. “This damage has the potential to lead to a loss of integrity and containment, leading to potential pollution incidents, risks of explosion from vapours and loss or contamination of product by water.

Visual inspection is a useful first step to identify, obvious surface damage. The typical affects will be invisible weakening or damage to joints, welds and the materials themselves. Long term effects may be accelerated. Weaknesses created may not manifest as leaks immediately but the potential for future loss may be created. I think it is fair to say that tanks and their installation are not typically designed or manufactured to absorb the forces and movement incurred during even a small seismic event and this can therefore lead to damage of vulnerable joints, welds, pipe connections and corroded or damaged material.”

More detailed evaluation such as pressure testing, wet-stock reconciliation can all help to provide assurance of the current integrity of the infrastructure, however none of these methods can predict any increase in the potential for future events, says Preece. To guard against these, integrated, continuous monitoring systems and alarms, reliance on physical secondary containment such as bunds are all useful if in place.

But if these containment measures are not in place, which is generally the case with most tanks in South Africa that were built before international regulations came into force, financial solutions, such as insurance, become more important. Environmental liability insurance, may not be able to prevent an occurrence, says Brice, but it will ensure that the resources are in place to respond appropriately should an event occur.

“The challenge and the industry is that most people see the word pollution in their general liability policy and think that they are covered. The problem is that this cover is generally only for sudden and accidental events,” says Brice. “The main risk with these tremors and other similar events is that the pollution will only be detected weeks, months if not years later, and will not be covered by this general liability policy wording. A specialist environmental product is required to cover these unique types of events which are becoming more frequent.”

Itoo offers the only environmental pollution cover in Africa which doesn’t discriminate between sudden and accidental and gradual pollution. “It’s a claims-made policy, so we don’t really look at when the pollution occurred”, says Brice. “So long as the claim occurs in the policy period, we will respect it. Of course, this is all subject to a risk assessment which is performed at our cost, but in our experience, only the really old tanks of 50 years or more are excluded.”

For more about the specialist team at ITOO visit the ITOO website.