Issue link: https://maltatoday.uberflip.com/i/1492490
maltatoday | SUNDAY •12 FEBRUARY 2023 9 INTERVIEW rocks, but also public safety just on the ground movement it- self; but also, on the local geologi- cal conditions. There are areas in Malta, for instance, when the rock is either fractured, or weak… and these ar- eas are more susceptible than oth- ers. An earthquake or nearby rock excavation can 'trigger' ground movement in these rocks, which would affect overlying buildings. In other words: it would not be the 'earthquake', so much, to cause all the damage – although earthquakes certainly do cause damage; as we saw in Turkey. It will also be the susceptibility of the underlying rock and the na- ture of that rock, that results in buildings collapsing. The old Mdina Cathedral is, in fact, a classic example. There is evidence that the underlying rock is fractured – the effect of frac- tures can be seen, to this day, in the bastions – so even if the epi- centre of the 1693 earthquake was around 150 kilometres away, the rock in Malta was still susceptible to the seismic waves; and this is what caused the old Cathedral to collapse. As for whether we 'know enough about local geology': the answer, unfortunately, is 'no'. We need to know a lot more, and there are structures that need to be studied closely. The geology of Malta is more complex than what is be- ing presented by the Authorities. Take the 'updated' geological map recently published by the Conti- nental Shelf Department: it has several omissions and errors. If there were a National Geological Service in Malta – it would also produce maps of 'high-risk' are- as would be most susceptible to damage, in the event of a large earthquake, flood or rock excava- tion. There are other issues apart from earthquakes, too. Climate Change, for example; and flood- ing – which is another problem we are experiencing on a regular basis, today. We already know that there are areas which are particularly prone to flooding, but there could also be cases of associated 'slope instability'… re- sulting in ground movement, for example. This is what I meant, earlier, by stating that geologists provide an invaluable service, to both soci- ety and the State. If we had this information available – which we would, with a National Geological Service in place – citizens would feel more reassured, and more protected. Because right now, there is no information whatso- ever. No wonder people become anxious in this country when they hear about earthquakes. If I'm understanding correctly, Malta has never 'mapped out' these high-risk areas: which also implies that, when the Planning Authority issues de- velopment permits, it does so in the absence of any geological data. Am I right so far? And if so: how much do you think this has contributed, to Malta's rate of construction accidents? You are certainly correct to say that, when the PA issues permits, it doesn't consider the underly- ing geology. It is, in fact, a classic case of 'Russian Roulette': and that, by the way, is a phrase used in the report issued by the Build- ing Industry Technical Commit- tee, headed by [retired Judge] Lawrence Quintano – which was commissioned by the Prime Minister [following the death of Miriam Pace in 2020]. The Quintano Report argued that Malta's construction indus- try is 'playing Russian Roulette with people's lives'; because when you excavate in an area, without knowing anything about the un- derlying geology… you could be lucky, and find that the rock un- derneath is stable (in which case, it would be perfectly safe)… … but you could also be 'un- lucky', and excavate into a geolog- ically high-risk area. In that case, even if you only go down only two or three metres, the stress in the rock and discontinuities might trigger failure: including – as was the case with several of those acci- dents – of buildings that are adja- cent to the construction site. And it is important to empha- size that in the cases where there was rock excavation, all the recent partial or total collapses of build- ings we've had, without exception, were related to failure caused by rock excavation. I'm saying this, because there are some people who are trying to 'decouple' these two issues: as if those accidents happened 'randomly'… Unfortunately, the legal require- ments in this country are limited to the extraction of cores without requiring the expert input of a ge- ologist. If we keep ignoring the underlying geology and exclude geologists during excavation, we will have more of these failures. Do you see a connection, be- tween the fact that 'some peo- ple' are trying to discredit the MCG's concerns; and that the MCG itself is finding it so diffi- cult to achieve State-recogni- tion? Let me put it this way: the same Quintano report also concluded that 'the perit can no longer be the only expert'. We agree with this: because there are other areas of expertise, apart from architecture and civil engineering, that are also involved in the construction pro- cess. We need other experts: archi- tects are 'designers' who design buildings and their founda- tions… but they don't 'design rocks'. It is Nature that designs rocks; and rocks – being 'de- signed by Nature', so to speak – are very complex materials which can be understood by geologists. They've been there for millions of years; and as such, they have a long history of stresses which have been acting upon them and deformation – including tectonic stresses. It is the job of the geologist to study, and analyse, the layers of rock that we excavate into, and build upon. This is why – in all other European countries, except Malta – it is normal to have geolo- gists involved in the construction industry: especially when it comes to assessing the safety of excavat- ing… and tunnelling, as well. Recently, there has been a lot of talk about tunnelling in Malta: a tunnel between Malta and Gozo; the creation of an underground metro system, etc. But how can we even consider 'tunnelling', at all… if we don't even involve geol- ogists in the planning stage? You took the question right out of my mouth. Given that – as you seem to be suggesting – we know so little about the underlying geology of the Gozo channel… what do you yourself anticipate, when (or if) the tun- nelling actually starts? I don't want to delve into the is- sue of whether we should actual- ly have a tunnel, or not. Because that's a social/economic issue, which should ultimately be decid- ed by others. But let's say, for argument's sake, that we do go ahead with this project. The first thing we would need to know is the stratigraphy of the rock-formations beneath the seabed; and especially, where the faults are; and what are the 'offsets' between those faults (i.e., the vertical distance between the different layers). Because we might have a situation where we'll be tunnelling through limestone, one minute…then suddenly, we'd be tunnelling through clay. Unfortunately, the offsets in the faults between Malta and Gozo are quite large: even exceeding 50 metres, in some places. And this will create problems. It doesn't necessarily mean that the tunnel itself can't be excavated, at all; but we do have to be at least aware of these issues, before actually tun- nelling… And there've been no attempts to find out so far? Well, government did invest in a seabed investigation, between Malta and Gozo. They extracted a number of cores - or samples of the underlying rock – and I believe that they extracted about 2km of core: which is quite a lot (and very expensive, too). But then, who actually logged those cores? An Italian engineer. And why an Italian engineer, in- stead of a Maltese geologist (of which we have several, by the way)? Because when the govern- ment issued the call for tenders, it didn't pay any attention to the ge- ological aspects of the operation. An Italian engineer will not know anything about the stratig- raphy of the Maltese Islands. And in fact, when you look at those logs… they don't even make sense. After spending all that money, we are left with information that is practically unusable: apart from the fact that there are large 'gaps', of about 20 or 30 metres, where there is no information at all in the logs; and the tunnel may have to pass directly through those un- known areas. To put that into perspective: when the Channel Tunnel [be- tween UK and France] was built, they also extracted cores from the seabed. But it was geologists - it was actually the British Geological Service; of the kind that we don't have in Malta – and who logged those cores: metre, by metre. THAT is the way to do things. It doesn't mean you're going to be completely, 100% safe, naturally; but at least, you would know what you're actually tunnelling into. To do that, however, we need to involve geologists in the entire process. And we're not doing this at all, right now.