John Hancock Potable Water Tank Inspection

CommTank was hired to provide a cleaning and inspection service at the John Hancock Towers in Boston, MA. The Hancock Towers have an 8,000-gallon wooden and a 6,000-gallon streel aboveground storage tank that supplies drinking water to the building. Before work could begin on the tanks a written health and safety plan and a confined space entry permit (per D-129 CFR 1910.146) was provided to the client. Both tanks were pumped out, entered and power washed. All water, dirt, and foreign material were removed manually from the tanks. The tanks were disinfected in accordance with industry standards and recommendations including, but not limited to, the applicable provisions of AWWA, NSF/ANSI, or the other national standards developed by ANSI-accredited organizations.

The wooden water tank required inspection of the sanitary conditions of the tank including the presence of sediment, biological growth, and floatable debris. CommTank’s inspector performed an examination of the general condition and integrity of the tank, including but not limited to the condition of overflow pipes, access ladders, air vents, roof access hatches, screens, structural supports and steel bands. The tank was inspected for evidence of rotting, cracking, and/or leakage in both the interior & exterior of the tank.

The steel water tank included an inspection of piping and connections, and fittings. The inspector performed an ultrasonic thickness test on interior and exterior walls using an ultrasonic thickness gauge. The condition of the tank shell, roof, vent and welds were inspected for corrosion and erosion.

CommTank provided a written Outcome Report that included the following information:

  • A written summary and recommendation based on the inspection results
  • The recommended date for the next inspection, based on the deterioration rate calculated
  • Photos of interior and exterior of tank
  • Water sample results