The hearing was dramatically halted in September when the agency admitted it had made mistakes in its evidence. They came to light after a question from an opponent of the scheme.
The agency had miscalculated the amount of traffic that would use the by-pass.
The hearing was adjourned to allow time for the mistake to be corrected.
When it resumed at Stalybridge Civic Hall yesterday, the Highways Agency asked for another adjournment after its own checks revealed mistakes in the revised evidence.
Opponents called it a `farce' and asked for the hearing to be abandoned.
Stephen Greenhalgh, Highways Agency project leader, said: "We were informed there are further anomalies, in addition to those that were identified back in September.
Implications
"It will take the Highways Agency some time to understand the implications and what actions are necessary."
He said there will be a knock-on effect on the environmental assessment, which the agency will not now be able to publish on November 30.
Asked by inquiry chairman John Watson if the agency evidence submitted since day 13 should be discarded, Mr Greenhalgh said: "The changes to the evidence on revised traffic figures, all that evidence, should be discarded and we would have to resubmit evidence based on the correct traffic forecast."
John Hall, who represents the people of Denton and Audenshaw, said he found the Highways Agency's actions `unbelievable'.
He said: "The incompetence is absolutely staggering and it is an insult to the inquiry. This is going to descend into more farce than it is at the moment."
Mr Hall repeated earlier calls for the hearing to be halted as it `was no longer credible'.
Mr Watson said: "It is an extraordinary situation, but it is not one we can't cope with."
He said he would adjourn the hearing until December 18.
The 3.5 mile by-pass would divert traffic away from the A628 and relieve congested roads in the villages of Mottram, Tintwistle and Hollingworth.
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John Hall (07/11/2007 at 10:29)
Errors were found then and the HA introduced suggested corrected errors evidence in June.
In September this June evidence was also found to have errors,so again the PI was adjourned,and so this latest declared flawed evidence,is not acceptable.The HA/Dept of Transport have vast levels of Public funds available to present over the past 2 years to have produced accurate evidence,so no longer is this PI credible.
I would think the Tameside Council costs alone already surpass £1 million of the Council Tax payers money,and the HA costs at least £1.6 million,and still the Public Inquiry is no further on than in February 2007 all due to error ridden evidence by the very people who are responsible for transport data across the UK.
Ruth Kelly MP knows about this deplorable situation costing millions without result but prefers to divorce herself from her role in this situation as Secretary of State for the Department of Transport,even though her intervention has been requested.If you enjoy seeing £millions of your money used FOR NOTHING,then so be it.