Background

The Deer Island Sewage Treatment Plant is the 2^nd largest of its kind in America. It deals with up to 1 billion gallons of waste sewage from the greater Massachusetts area on a daily basis.

Description

In 2008 Reliable Roofing & Sheet Metal undertook a complex roofing project for the Deer Island Sewage Treatment Plant. The project included installing several EDPM roofing systems and reinforcing these systems to support solar water heating roof units. The job presented many challenges uncommon in typical commercial roofing projects. These included:

·         No hot works allowed as explosive gases present in the atmosphere

·         Extreme cold within the Cryogenics building

·         Working on narrow platforms at extreme heights

These conditions required innovative thinking from Reliable Roofing’s design team and installers. Detailed planning and cooperation with the project management team lead to the following solutions:

Removing the existing roof

This process would usually involve machinery with the potential for producing sparks. Due to the presence of explosive gasses this operation could not be carried out in the normal fashion. Our roofers used only hand tools and spark free methods to minimize the risk of explosion.

Extreme cold in Cryogenics building

This building was a unique challenge as it stored liquid oxygen at almost -238°F. Storing this cold liquid lowered the roof temperature below the recommended for EDPM installation. Our team ensured the manufacturer could guarantee the products for this unusual situation and heated the products in offsite containers prior to installation.

Working at heights

The egg shaped digestion units posed a difficulty for our installers as the walkways between units were located up to 130ft off the ground. These narrow walkways had no safety railings. Our installers underwent special training to safely work at these heights. A system of fall arrest was developed using fall arrest eyes drilled into the deck every 6 feet. The worker clipped on to one eye advanced 6 feet, with a second lanyard clipped onto the second eye and then removed the first lanyard. This ensured the worker was constantly restrained from falling with a maximum of 6 feet lanyard at any time.

Nauseous gases mitigation

The potential for gasses to build up beyond harmful levels was minimised by our staff wearing gas detection monitors. These monitors detect the presence of dangerous vapours and limited the risk for our employees.

Crane planning

Each crane lift had to be carefully planned as many hazards existed on site. These included overhead power-line, exhaust stacks and buildings in close proximity. The crane drivers and project superintendent conducted a risk analysis for each lift to identify and mitigate possible risks.

This project also required full insurance from Factory Mutual. This is distinctly different from the more common practice of meeting Factory Mutual I-90 standard.

This project was unique, but it clearly reflects Reliable Roofing’s experience, knowledge and esteem within the commercial roofing industry.