Archie Anderson suffers from Cerebral Palsy and has difficulties walking. But a £50,000 operation in St Louis Hospital, Missouri, could give him a chance.
The workers, who are being made redundant, have donated their entire social fund to three charities - one of which is Archie's charity.
The donation from the Rio Tinto workers brings his total to more than £45,000.
Marie Anderson, Archie's mother, has tweeted: "Thank you so much to the workers at Alcan for your wonderful donation to Archies Dream."
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The children on board were from Easingwold School and were travelling along roads affected by heavy rain and flooding after Christmas.
The walls had been closed to the public at the weekend amid fears of a collapse.
Junk food advertising is to be banned across all children's media - including online and social - in a bid to tackle childhood obesity.