The wall collapsed on Tuesday while the workers were preparing the mortar, and they were rushed to hospital.
Riebeek West resident Marquirette Jacobs said: “The building is being done on a site that used to be a dump site and this ground needed to be rehabilitated.
“We have been made aware that the environmental study said the land was not suitable for construction.
“Even the foundation is not properly done and the completed homes have cracked walls...”
Jacobs said residents had also complained that infrastructure was not in place yet, leaving them without water and electricity.
ASLA Construction chief executive Werner Jerling said an investigation into the incident was under way and the Swartland Municipality was investigating the matter independently.
“In the case of one of the walls, two employees employed by our subcontractors had been loading sand near the wall when the wall fell over and debris hit the two workers.
“The workers were treated on site, were transported to the local hospital and eventually moved to Tygerberg Hospital where further tests were done to rule out any internal injuries.
“One of the injured was released and is recuperating at home. The other worker is still in hospital in a normal care level ward.”
Swartland Municipality Development Services director Jo-Ann Krieger said to date, 64 families had moved into their new homes and all fixed infrastructure to the homes was in place prior to their occupation.
“The Swartland Municipality owns the land and will decide on the most appropriate use of the land over time.
“Infrastructure is in place, but energising of the homes is dependent on registering the smart meters to occupants.
“The process is in place and the first batch of occupants (30) will be energised in the next day, Eskom assures us.”
Krieger said the allocation of houses had been done in terms of council policy aligned with national and provincial guidelines.