The unfinished Harmon tower at CityCenter is virtually unrepairable and could collapse in a "code-level" earthquake, according to a structural engineer hired by MGM Resorts International who examined the 27-story building.

In the report, members of Weidlinger Associates of Marina Del Rey, Calif., said they ran several tests on the building and found missing or misplaced reinforcing steel in columns, beams, shear walls and transfer walls throughout the tower below the 21st floor.

"The construction defects in the tower observed to date are so pervasive and varied in character that it is not possible to quickly implement a temporary or permanent repair to remediate the defects, or even determine whether such repairs can be performed," Chuckwuma Ekwueme, an associate principal with Weidlinger told CityCenter Vice President of Facility Operations William Ham in a letter dated Monday.

A "code-level earthquake" is based on the probability of an earthquake strong enough to damage structures occurring once every 500 years. The rating varies by region, depending on several factors including fault lines and soil conditions.

In the letter, Ekwueme said that if a code-level earthquake were to take place, "it is likely that critical structural members in the tower will fail and become incapable of supporting gravity loads, leading to a partial or complete collapse of the tower."