The Unite members are in a dispute with their employer, Veolia, because the firm has not recognised their union.
Unite said it represents almost 100 workers, making up about 80% of the Lumley Street depot, but GMB is the sole recognised union.
Veolia has asked for the matter to be decided by the Trade Unions Congress.
Unite regional officer Shane Sweeting said: ‘Veolia could end this dispute tomorrow by doing the right thing and recognising the workers’ chosen union, Unite.
‘Veolia bears complete responsibility for the rubbish that will pile up across Sheffield because of its refusal to recognise Unite.’
Sheffield City Council said it was working with Veolia to ‘make sure there is as little disruption as possible’.
This article first appeared on LocalGov.co.uk.
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