Video of a black substance flowing out of a pipe and into the sea by Fort Ricasoli has gone viral, with social media users outraged by the blatant pollution of Malta's marine environment.

The discharge, which many social media users believe was oil, came from the Ricasoli Tank Cleaning Facility, a spokesperson at the Environment Resources Authority told Times of Malta.

"ERA compliance officers ordered the facility to cease all activities with immediate effect, following which the discharge was confirmed to have ceased," the spokesperson said. 

The spokesperson did not specify whether the discharge was oil, despite being pressed on the issue. 

The tank cleaning facility is operated by Waste Oil Ltd, which was handed a 30-year lease to manage the facility in 2013.

In video uploaded to Facebook yesterday, the black substance can be seen streaming into the sea at a steady rate. The footage has been viewed well over 140,000 times and the post shared by more than 6,000 Facebook users. 

This is not the first time black discharge has flowed into the sea at Ricasoli. 

In January 2015, following reports of similar discharges, a spokesperson for Waste Oils Ltd told Times of Malta that it had investigated the effluent and concluded it could "not be rationally explained." 

At the time, marine biologists Alan Deidun and Victor Axiak had called for independent water tests to verify the company's claims. Prof. Axiak now heads the ERA. 

Waste Oils Ltd is owned by Falzon Group. Its Rinella facility receives liquid waste from vessels and from industry for treatment to remove oils and other chemical contaminants prior to discharge into the sea.

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