I think the gasholder/gasometer is a listed building now.
There are not so many left in the country, as they are high maintenance and a relic from the days when gas was produced and stored locally.
Its only function now is to even out the pressure as demand changes during the day, as I understand it, perhaps giving the underground high pressure gas pipes a longer lifespan.
http://news.bbc.co.uk/1/hi/uk/264609.stm

Can these things explode? History tells us yes, and as the country's expertise on these things diminishes, I imagine that any maintenance gets more dangerous.

Sure, almost certainly it is more dangerous regularly crossing the road (esp at the Davidwhiting crossing maze at Kangley Bridge Road) than living near to one of these things but it is an unnecessary risk all the same.

It should be (carefully) decommissioned imo, and the interior turned into a museum with lots of history of the site and working demonstration of the old process of making coal gas, and sure miniature demonstrations of the explosive nature of gas.

Then we can build the shopping scheme of our dreams unhindered...