Heartland Tank’s Chris Brooks was featured in an article by AgPro:
Chris Brooks, president of Heartland Tank Services, Inc. stressed the type of inspection routinely needed for large storage tanks that have been in service for a few years during the 2011 National Agronomic, Environmental, Health and Safety School.
Brooks said, “Due to the corrosive nature of most liquid fertilizer solutions and weight (specific gravity) of those solutions, liquid fertilizer storage tanks require routine and qualified mechanical integrity practices to maintain a safe storage environment.” A major concern in storing liquid fertilizer he explained is having a tank that will withstand the specific gravity of liquid fertilizer usually 1.3 to 1.5. For instance, oil has a much lower specific gravity, and thus requires less thickness of steel for proper containment.
Brooks conveyed detailed information on API 653 (American Petroleum Institute guidelines) inspections for above ground storage tanks. A very important part of receiving the API 653 Certified Inspector designation that he holds is obtaining an NLPA Level II Ultrasonic Thickness (UT) technician certification.
All areas inside the tank need to be accessible so that the inspector can reach high and low for the inspection. Only looking at the bottom two courses of steel is not acceptable.
See full article from AgPro: Large Storage Tank Inspection