Alpine Painting & Sandblasting Contractors

Alpine Brings a Glowing Approach to a Chilly Rehabilitation Project

The Suez Spring Valley Standpipe project was an interior/exterior rehabilitation of a two-million-gallon potable water steel standpipe tank. The tank was made of carbon steel and the existing coating system was over 20 years old and was beginning to rust in many areas. Alpine Painting and Sandblasting’s first challenge to overcome was having to work through the cold and windy New York winter and needing to redesign the specified coating systems. Alpine worked with the engineer and owner to redesign the coating system to move from traditionally warmer weather coatings to coatings that could be used at or below 20 degrees Fahrenheit.

Working efficiently through the winter is a challenge. For the interior work, Alpine used dehumidification to maintain the blasted steel so that the interior lining could be applied at the end of the surface preparation and when the temperatures were more favorable. The exterior primer could be applied to 20 degrees F and the exterior intermediate and stripe coat product could be applied to 0 degrees F. The exterior finish coat minimum temperature was also 20 degrees F.

The exterior was sandblasted to SSPC SP6 (Commercial Blast Clean); interior was sandblasted to SSPC SP10 (Near White Metal Blast Clean). Alpine used G50 steel grit and an ARS S4 steel grit recycler for the coating’s removal. The coating system was provided by Sherwin Williams. The exterior coating system was Corothane 1, Dura-Plate 235 and Hi-Solids Polyurethane. The interior coating was Polycote 115 at 25-40 mils DFT. All coatings were applied by spray, the exterior was airless spray and interior was plural component spray. The exterior was accessed by a system scaffold. The containment system met SSPC Guide 6, Class 2A.

Always With an Eye Towards Safety

The crew was OSHA 10 or 30-hour trained. Suez did specific training with crew members on their job site customized to their protocols. A supported scaffold system was used on the tank exterior fully decked with a guardrail system. A suspended scaffold system was used on the interior with independent lifelines for each worker. While blasting and painting all employees used proper respiratory protection equipment for the task they were performing.

All interior work was performed on suspended scaffolding so special training was required to use this type of equipment. All workers were tied to independent safety lines. The exterior system scaffold was fully decked at all levels and had a full guardrail system. All workers wore proper respiratory protection equipment while sandblasting and applying the protective coatings. 

Alpine Innovation Meant Both Compliance and Conservation for the Client 

As mentioned before, Alpine used a G50 steel grit abrasive by Ervin Industries and an S4 steel grit recycler by Advanced Recycling Systems to classify and reuse the blast media. This resulted in a waste minimization on the project. Using conventional expendable abrasive, Alpine would have used approximately 10 roll off containers (200 yards) of waste. Due to the recycling equipment and steel grit, the crew only disposed of 30 drums (8 yards) of waste. Waste minimization also helped the owner with New York Department of Environmental Conservation compliance.

Water quality standards continue to become more stringent and may require modifications to a typical tank to stay compliant. On this project, Alpine installed a mixing system called Tideflex TMS. The TMS is a passive mixing system to improve water quality inside the tank by preventing stratification of old and new water. When stratification occurs, chemicals added to the water to prevent bacteria growth stop working and may cause the water to become non-compliant with the regulations.