Sue Rogers has been appointed interim deputy director of education, a new role which is costing the council £864 per day plus daily expenses of £100.
Julian Wooster, director of children's services, said: "My view is children can't wait - hence why we have a very capable interim who has joined us."
He added that a permanent person should be in the post by Christmas.
In March, the council's children's services department was rated "inadequate" by Ofsted with its report, describing a "corporate failure" to keep children safe.
The new role has been created, according to Mr Wooster, so he can concentrate on urgent improvements needed in social services.
"It's a role most authorities have and the person carrying out the interim role has been doing that role in another local authority," he said.
"I don't generally believe that interims are sustainable and members have made it very clear to me they don't expect this person to be in role for that long."
He added that the £964 a day cost, also included agency fees and relocation expenses.
"We don't pay any annual leave and we don't pay any sick leave for this role or any pension," he said.
"It's also a short term contract and I'm very confident that we can recruit in September to enrol on a permanent basis."
Somerset County Council has defended its decision to pay nearly £1,000 a day for a temporary employee.