The two proposed sites for a new incinerator have attracted opposition from local groups concerned about the impact on the environment.
Cardiff Against the Incinerator and Stop Newport Incinerator say that a better solution to domestic waste would be to increase recycling targets.
The two bidders, Veolia and Viridor, say that the plans represent a major investment and electricity generated by the incinerator will help power local homes and businesses.
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Wales have qualified for the Euro 2016 quarter finals after beating Northern Ireland 1-0 in Paris.
A rally has been held in Cardiff following the EU referendum to show support to migrant communities.
It's 0-0 at half time in Paris as Wales face Northern Ireland in the last 16 of Euro 2016.