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Demoing Phillips Exeter Academy's Central Boiler Plant

The Challenge:
Remove and replace boilers encased in brick and asbestos.

The Players:
Phillips Exeter Academy
EnviroVantage
Harvey Construction

The Solution:
EnviroVantage used several piece of equipment to safely demolish and remove the brick, concrete, asbestos and the old inefficient boilers at Phillips Exeter Academy.

 

Phillips Exeter Academy (PEA) originally had six enormous boilers encased in layers of brick and asbestos that dated back to the early 1900's. The replacement of the old units with new, more efficient boilers would greatly increase the steam production efficiency of the heating plant, save time and money, and eliminate the unnecessary risks to the employees working in the plant.

PEA contracted Harvey Construction as the General Contractor, while Harvey and PEA selected EnviroVantage as a subcontractor.

Phase I of the boiler replacement project started with removal of thousands of linear feet of asbestos-containing material. Multiple areas of asbestos on the steam lines needed to be abated, allowing the mechanical contractor to cut and cap lines and re-route the steam to ensure there was minimal down time for the campus to be without hot water.

With the steam re-routed, EnviroVantage placed the entire area around the boilers under containment and negative pressure. A massive plastic wall was erected to divide the containment from the rest of the boiler facility that needed to remain operational throughout the entire renovation.

The company used glove bags to remove asbestos pipe; however, when the insulation was removed, the heat of the pipes melted the glove bags and even the gloves of the men working on them, a common industry-wide problem. The pipes required at least three to four days to cool down, even after being shut down and drained. EnviroVantage workers also had to wear mandatory protective suits and respirators while working from man lifts and ladders to access the pipes suspended from the boilerhouse's high ceiling over 30 ft. off the ground. This created virtually unbearable temperatures to work in. Staying hydrated and taking frequent breaks, the crew took the necessary safety precautions in this environment.

Next, EnviroVantage began the demolition portion of the project by demolishing the suspended steam lines, ranging from eight to 14 in. in diameter. The workers needed to maneuver around live steam and gas lines. Chain falls, forklifts, and skid steers were utilized to lower the pipes from the ceiling. EnviroVantage purchased a Bobcat 337 excavator needed specifically for this job, but getting these machines into the building was another challenge. There was one set of double doors wide enough to fit the equipment through, but the opening was 10 ft. above the ground. They used a tow truck to pick up the excavator, extend the boom and lower it in to the building. This took precision and patience with a live gas line running directly above the door opening and a live condensate line located right under the door opening.

The only way to remove the loads of debris was to lift it up and out of the double. To accomplish this task, EnviroVantage used two mini skid steers and the excavator to lift all the debris into a bucket that was attached to a Lull on the outside of the building. The Lull then pulled the waste out and turned around to place it in to the correct dumpsters.

The company used several torch cutters to cut the steel tanks and tubes down from each set of boilers. Each brick shell had three huge steel tanks inside and about 150 steel tubes connecting the tanks together, all of which were meticulously cut into sections, lowered down, and hauled out. EnviroVantage was then able to cut down the rest of the steel structures along with all of the beams and supports, leaving a bare floor and ceiling.

The breeching and ductwork were cut in to large sections and removed. The team then sliced the concrete floor along the center of the column line, and the side on which the boilers had been was pulled up by jack hammering the concrete with the excavator. The leftover water used to hose the dust down while the demo was under way then had to be pumped out and disposed of properly.

Once the water was gone, EnviroVantage scraped the area with skid steers, picking up any loose debris. The crew then used a concrete sealer to lock down any leftover dust. After the new steel was built and a concrete floor poured, EnviroVantage came back to coat the ceiling with fresh white paint and give the finished boiler room a clean, sharp look.

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