Section 1809.01 Aggregate Pier or similar Ground Improvement Foundation System is added. Construction tolerance of the pier installed location shall not be more than 6 inches. For the 3-pier footing, the centroid of the installed piers, the centroid of the footing and the centerlines of the supported column shall be coincided. The capacity of the single-pier-, and 2-pier footings used in supporting column/wall loads shall be reduced due to the eccentricity (allowed construction tolerance) of the pier location.