Pembroke-St George’s tunnel will produce 100,000 cubic metres of waste

A proposed tunnel to link the db Group’s City Centre high-rise to Pembroke will produce a staggering 100,000 cubic metres of construction waste – half of which may be reusable in the tunnel structure itself.

With the addition of the tunnel, the total amount of construction waste produced by the 37-storey tower project, will be increasing to 436,085 cubic metres, equivalent to nearly half the amount of construction waste produced in a single year.

50,000 cubic metres of the rock material could be reusable during the construction phase as part of the shotcrete used to layer the tunnel’s walls. But tests still have to be conducted to assess the quality of this material and the feasibility of its use.

The 1.4km underground tunnel is being proposed to alleviate the daily increase of 7,000 car trips brought about cumulatively by the City Centre and Villa Rosa developments.

According to the latest plans by the db Group, the tunnel’s western portal of the tunnel will be located on a new road connecting Triq il-Mediterran to the Coast Road, whilst the eastern section will link to three underground car parks at City Centre, and the Raddison Blu and Corinthia hotels.

The tunnel will be excavated by an underground rotary header and will pass under a Natura 2000 site, but the developers’ environmental impact assessment reports that no habitat loss or damage is expected since the excavation work will be underground.

The excavated material will be temporarily stored on site in a stockpile in an area in Suffolk Street behind the proposed Chinese embassy – the stockpiles themselves will not exceed three metres in height and will be covered to minimise dispersion of fine dust particles.

Heavy vehicles will be on site at least every two days to collect the excavated waste and transport it to disused quarries. A total of 14,000 trips are envisaged throughout excavation phase in order to transport this material offsite. This would amount to between 50 and 80 trips a day. The trips will not be undertaken during peak traffic hours, both morning and afternoon, in order to minimise the traffic impacts along the route.

Additionally, the material earmarked for shotcreting will be crushed either on site, or at the construction site closer to the former Institute of Tourism Studies.

The EIA warns that since the rocks to be excavated are quite resistant, the noise and vibration levels are expected to be very loud.

Works will be taking place over a period of 6-9 months but no reference is made to the impact the noise will have on residents living along Triq il-Mediterran.

Transport Malta has not yet taken any decision with regards to the funding of a proposed tunnel that will link City Centre to Pembroke. The land transfer contract clearly states that the government has to “undertake at its sole cost, risk, legal and financial liability” the “required improvements to the road and utilities infrastructure leading to the site”.