A move to save money on the Maidenhill Primary School build has ended up leaving the council out of pocket.
Local authority chiefs had made an agreement for Cala Homes and Taylor Wimpey to provide topsoil from the neighbouring housing development.
The idea was to save cash which would have been spent importing the material from other sites.
But East Renfrewshire Council will now have to stump up £67,000 to remove the topsoil after tests found it to be substandard.
Cala and Taylor Wimpey have agreed to take back some of the material, but council officers are now in the process of making a claim against the developers to recover the costs.
In a report, Andrew Cahill, the authority’s director of environment, said: “The council made an agreement with Cala and Taylor Wimpey for the development of the Maidenhill area for housing.
“As part of that agreement 5.54 acres of land was transferred to East Renfrewshire Council for the purposes of constructing a new primary school and nursery to cater for increased educational demand due to housing expansion.
“As part of the agreement the developers of the housing site were to deposit 5600m3 of topsoil on the school site for construction and landscaping purposes, thus saving the council the costs for importing soil from off-site.
“Although 5600m3 was requested, approximate 6400m3 was delivered. The topsoil delivered failed analytical tests and was declared unsuitable as topsoil.
“Bam Construction Ltd has managed to use a substantial portion of this material as subsoil to mitigate the need and costs of transporting this material off-site.
“Cala and Taylor Wimpey have agreed to take back 1750m3 to their development site.
“The council will now need to import certified topsoil at an additional cost over and above the contracted sum.”
Mr Cahill revealed that council leader Tony Buchanan and deputy leader Paul O’Kane had to give urgent approval for the £67,000 to be spent removing and replacing the topsoil.
And he claimed that building work could have been suspended while a claim against Cala and Taylor Wimpey is ongoing.
He added: “Council officers are progressing with a claim against the developers, under the section 75 agreement, which states that they should provide ‘a quantum of topsoil on site’, which would recover the costs.
“One option available to the council would have been to suspend the work until this claim has been resolved. However, this would have resulted in the school not being open within the required timescales. Therefore, this was not felt to be a viable action.”
The Maidenhill Primary School project, which commenced on May 7, is expected to cost £15.3million.
The neighbouring Maidenhill housing development will see 106 new detached homes built.