Premium Content Subscriber only Mine workers will today plead their case before a Senate Inquiry on proposed workplace law changes which the union has labelled a "detriment" to Mackay and its resources industry. Tightening the definition of casual employment will be a key aspect of a 27 page submission union representatives will present to the committee, which is sitting in Townsville. CFMEU Mining and Energy Queensland southwest vice-president Shane Brunker said the casualisation of mine jobs was a "cancer that's spreading through the industry". He said there were thousands of workers across the Bowen Basin, contracted through labour hire companies as a casual employee but working a full-time roster without benefits such as annual or sick leave.