RETAINING WALLS Spiral Nail Wall, zero micro setback, NW Portland, OR Multiple Tie-Back Anchors/Shotcrete walls, West Hills, Portland, OR Pile and Helical Tieback Wall, Wilsonville, OR Cellular Concrete + Carved Shotcrete Retaining Wall, Lake Oswego, OR Shotcrete retaining wall, NW Portland, OR H Pile & Shotcrete retaining Wall, NE Portland, OR