The company behind Bluff's Tiwai Point aluminium smelter is again appealing against an Employment Court decision ordering compensation for union members for underpaid lieu days.
New Zealand Aluminium Smelters (NZAS) will make an application to the Court of Appeal this week, challenging the decision which the company says will cost it $20 million.
Shift workers moved from eight to twelve hour days in 1991 but continued to be credited eight-hour long days in lieu.
The Employment Relations Authority said they should have been credited with 12 hour days and upheld the decision on appeal last month.
Alan Clarence of the South Island Engineering, Printing, and Manufacturing Union said the appeal was tough on the workers and staff were disappointed.