Rubbish collection staff and street cleaners in Waltham Forest are to be balloted on taking strike action during the Olympic Games.

Unite and the GMB unions say their members who work for council contractors Kier are furious over a range of issues, with an alleged recent cut in overtime pay being "the final straw" - although the firm denies any wages have been reduced.

Tommy Anderson, Unite chair for Kier workers in the borough, said there had been unanimous support for a strike during an informal vote among 80 members last week.

An official ballot could be held early next week.

He said: "In my 19 years working in street cleaning I've never seen staff this angry before. They are furious."

The dates for the possible industrial action have yet to be decided, but Unite says many households will not have their rubbish collected or streets kept clean if the strike did go ahead.

Staff are reportedly disgruntled at recent changes to overtime pay and their treatment by management.

A Kier decision to draft in 91 low-paid agency workers to carry out extra work during the Games has also prompted concern.

Insiders say the council has reportedly paid the firm £800,000 for the work, which was not put out to tender to ensure value for money.

The authority has not confirmed the amount but said it was confident that value for money was achieved from the deal.

But unions say none of the agency staff will have a CRB (criminal records) check, and they also claim they will not have any health and safety training due to their "last-minute" recruitment.

Mr Anderson, who retired from Kier due to ill-health earlier this year, said: "These staff will be doing things like working in parks around children.

"How are parents going to feel knowing they could be criminals or paedophiles for all Kier knows?"

A Kier spokeswoman said: "No overtime has been cut. Agreements are in place with the unions to pay staff premiums during the Olympic period to cover revised working patterns.

"Appropriate health and safety training is provided to all staff working on the contract.

"Kier can only CRB check staff whose role dictates a requirement by law for CRB checks.

"We are not legally able to blanket CRB check all staff.

"In terms of employee complaints, from time to time, as in all companies, matters do get reported, and these are dealt with via our internal grievance procedures."

She added: "Contingency plans are built in to the way we run our business. In the event of a strike, Kier will continue to provide a full service to Waltham Forest Council with minimal disruption."

The news comes in the wake of revelations that Kier has been fined almost £50,000 by the council for poor performance since it took over the contract for collecting the borough's rubbish last autumn.

Police are also reportedly investigating a fraud involving both senior and frontline staff at the firm.

Mr Anderson said staff were also angry about the company's handling of the case, and alleged that some workers had been made scapegoats.

The Guardian is awaiting a comment from the council on if it has any contingency plans.

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