For these CTA station projects, INTERRA provided Quality Assurance services. Testing and inspection duties were performed on soil and concrete. For soil, compaction testing was conducted on the backfill and trenches, and footing bearing inspection. Compaction testing was performed on the base layer for under footings along with subgrade field density testing. Masonry grout and mortar samples were collected. For concrete, rebar inspection, slump testing, cylinder collection was being provided for slab infill, and samples collected for a concrete pour. Ductbank and foundation concrete testing and sampling was performed. Weld and bolted connections were inspected on the steel frame columns and on steel beams.