hmmm, good question. I haven't read any reports such as the one you have posted. However, I would say that there is a massive clean up operation required to clean up the city. You do notice a strong gas smell sometimes from some of the open wells in and around the city where they are actively taking oil from the ground.
There are a lot of open areas where the oil has been left to sit since pre 1993.
But as I say, the cleanup operation is massive, and will require an injection of a lot of funds, which hopefully will come from the revenue being generated from the current developments offshore/onshore.
I cannot comment on your remarks about the country/city being the most ecologically devastated area in the world.