A team of more than 30 social workers is starting to investigate a backlog of 1,000 child protection cases in Kent which have no dedicated case worker.
The special team was recruited at a cost of £2m after an Ofsted report last November found services intended to protect children were inadequate.
They are joining another 20 Kent County Council (KCC) staff redeployed to look at the cases from 1 April.
"Money should not be a problem," said KCC leader Paul Carter.
Ofsted's report said that in the worst cases, children were left unprotected and were at risk of significant harm.
KCC reviewed all of its 7,000 active child protection cases. By January it had identified more than 500 cases which raised cause for concern and given them new management plans.
New interim children's services boss, Malcom Newson, who took up his post in January, discovered that at one point 2,700 cases did not have a social worker assigned to them.
KCC's former chief executive and director of social services, Peter Gilroy, who stepped down last year, said he doubted whether any of the outstanding 1,000 cases involved children at risk of serious harm.
But he told BBC Radio Kent he raised concerns about child protection in the county more than two years ago.
"I did a report in February 2009 and even then I was starting to worry about a whole range of things that were happening," he said.
"I was concerned about the competence of senior management, the performance data that was coming and the training we were giving staff."
Jenny Whittle, cabinet member of children's services, said Mr Gilroy's report referred to issues such as high vacancy rates in social services
"The issue of unallocated cases was not brought to members' attention until Mr Newson was appointed," she said.
"The Ofsted report followed a glowing inspection report we received in 2008."
She said a recruitment drive for social workers had now brought down vacancy rates from more than 25% to just under 5%.
The team of 50 social workers focusing on the unallocated cases from Monday is expected take between three and six months to complete the job.
Since the Ofsted report, KCC's managing director of children's services, Rosalind Turner, has taken voluntary redundancy as part of a restructuring of senior management in preparation for budget savings.