I am not a mould specialist; therefore, I will not comment on the impact the observed mould (or material which appears to resemble mould) could have on the structure. I have included the details of a mould specialist below.
It is recommended the area is investigated further and rectification works undertaken as required.
Dr. Cameron L. Jones
B.Sc., Grad Dip App Sci. (Industrial Microbiology), PhD.
Biological Health Services
Telephone 1300 13 23 50
Head Office Level 1, 459 Toorak Rd, Toorak, VIC, 3142
Laboratory 7/4 Weddel Court, Laverton North, VIC, 3026
Did anyone have this issue during construction?