BIFFA has been investigated five times this year over allegations its crews have been dumping so-called “green” and “grey” household waste into the same wagons.

Although homeowners face possible penalities for “contaminating” recycling bins, in two incidents last month - in Moreton and, the Globe understands, Thingwall - crews mixed the contents of green and grey bins.

Wirral Council’s technical services director Dave Green said the crews concerned - who have since faced disciplinary action - had said they were attempting to clear the backlog caused during January’s big freeze.

Mr Green said in a statement: “Since, January 1, there have been five allegations made about green and grey bins being emptied into the same wagon. These allegations involved three different collection crews.

“Biffa has investigated the claims and with regards to the first crew, found no conclusive evidence to prove that both bins had been emptied into the same wagon. However, the investigation will be kept on record.

“A second crew has admitted emptying both bins into one vehicle and, despite previous instructions from Biffa management that this is not permitted, felt that they were helping to clear the back-log of waste that had accumulated following the bad weather.

“Having recognised the seriousness of their actions, this crew has volunteered to undertake a two-hour education programme with the council’s waste and recycling team to help them understand why recycling and correct management of waste is so important.

“Another investigation found that a third crew had mixed the contents of the green and grey bins and I can reassure people that Biffa has taken appropriate disciplinary action against this team to make sure that it does not reoccur.

“The council and Biffa remain committed to maximising recycling and thank residents for their contribution. We appreciate all feedback and as these investigations show, will always follow up any concerns.”