This is not a gas leak krub. Obviously whoever posted this has no real knowledge about what's going on.
A gas flare, alternatively known as a flare stack, is an elevated vertical conveyance found accompanying the presence of oil wells, gas wells, rigs, refineries, chemical plants, natural gas plants, and landfills. They are used to eliminate waste gas which is otherwise not feasible to use or transport. They also act as safety systems for non-waste gas and is released via pressure relief valve when needed to ease the strain on equipment. They protect gas processing equipments from being overpressured. Also in case of an emergency situation, the flare system helps burn out the total reserve gas.
On oil production rigs, in refineries and chemical plants, its primary purpose is to act as a safety device to protect vessels or pipes from over-pressuring due to unplanned upsets. This acts just like the spout on a tea kettle when it starts whistling as the water in it starts boiling. Whenever plant equipment items are over-pressured, the pressure relief valves on the equipment automatically release gases (and sometimes liquids as well) which are routed through large piping runs called flare headers to the flare stacks. The released gases and/or liquids are burned as they exit the flare stacks. The size and brightness of the resulting flame depends upon how much flammable material was released. Steam can be injected into the flame to reduce the formation of black smoke. The injected steam does however make the burning of gas sound louder, which can cause complaints from nearby residents. Compared to the emission of black smoke, it can be seen as a valid trade off. In more advanced flare tip designs, if the steam used is too wet it can freeze just below the tip, disrupting operations and causing the formation of large icicles. In order to keep the flare system functional, a small amount of gas is continuously burned, like a pilot light, so that the system is always ready for its primary purpose as an over-pressure safety system. The continuous gas source also helps diluted mixtures achieve complete combustion. Enclosed ground flares are engineered to eliminate smoke, and contain the flame within the stack.
I think a lot of the Map Ta Phut conflicts have to do with misunderstanding, insufficient information, and most importantly lack of trust, with both sides seeing each other as enermy. The fist two points can be fixed through proper education. But the latter point is the hardest one to fix because trust cannot be taught but needs to be earned.