Consultant Arup will now carry out a two-month review of Skanska's findings to identify potential liabilities to developer Aire Regeneration.
English Partnerships was due to sign a joint venture development agreement with Aire Regeneration in June: the joint venture was to sign a planning gain agreement with Leeds council in the same month. Neither agreement is now expected to be signed until September.
A source at Arup said: "The review is to make sure that we know of obstructions in the ground and its load-bearing capacity, to ensure the houses are positioned correctly and to know how to build foundations in every area of the site."
Aire Regeneration hoped to receive detailed planning consent for the first phase of 35 houses in July. However, the position of two houses will have to be changed, and the application resubmitted, in the light of the location of the mine shaft.
Skanska carried out its first site remediation last year for EP, which owns the site.
In January this year Skanska won a second contract to carry out site investigations. However, it did not begin work until April as a result of wrangling between Skanska, Yorkshire Forward, Aire Regeneration and EP over an agreement to protect the warranties obtained by the first site remediation.
An EP spokesperson said: "We ensured that Skanska did not carry out any site practices during the additional remediation works that might invalidate the warranties on the original work done, such as disturbing clean material."
