Metropolitan tackles confined space dangers
Now more than ever, municipalities are addressing the dangers of below ground pump stations to protect both entrants into confined spaces and the investment of systems themselves. The United States Department of Labor requires a permit for those seeking to enter confined spaces for system repair, accompanied by rigorous guidelines those involved with the entry must follow.
Moreover, flooding of below ground pump systems can lead to catastrophic damage of the systems themselves, often costing municipalities a great deal for repair or even replacement, and can lead to an emergency service call.
Metropolitan Industries recently renovated three below ground pump stations, giving each customer the ability to interface with the controls without entering the confined space. Another advantage of “above grade controls” is the avoidance of control system damage caused by a vault flood. Potential future projects such as submersible pump retro-fit into the existing wet well would be the next appropriate step to completely eliminate confined space entry.
City of Calumet City, Ill.
The City of Calumet City, Ill. recently came to Metropolitan for an emergency rehabilitation project following the flooding of a below ground water pump station.
“Metropolitan suspects the reservoir fill valve stuck open causing an overflow condition, thus filling the below ground pump station with water,” said Metropolitan salesperson Keith Girup. “The existing booster station was constructed many years ago when below ground systems were common. Metropolitan was able to repair and replace equipment quickly, and in the process improve the operation and energy-efficiency of the station by implementing variable frequency drives for constant pressure control.”
Another new piece of equipment included in the upgrade was a low-flow shutdown bladder storage tank.
“The new bladder tank supports the water system leak loads during low flow periods of time,” Girup said.
The system was also integrated into a city-wide SCADA system for enhanced monitoring and alarm notification. A flood switch was added to the pump room to ensure notification is provided in the event of a flood since the pumps remain in the below ground vault and are subjected to the hazards associated with such a location.
The primary advantages of the system upgrades are the reduced frequency of entering a confined space and overall protection of the equipment.
South Palos Sanitary District
Metropolitan recently completed a similar project for the South Palos Sanitary District.
“In this project, the customer decided to keep their drywell pumps below ground, but implemented above grade controls into a new prefabricated concrete building with an exposed aggregate finish,” said Girup. “The prefabricated building contains the controls, generator and a temperature control device, essentially eliminating the need to enter below ground in order to interface with the controls.”
Girup said that because the customer has decided to keep the drywell pumps below ground, it will still be necessary to go below ground to maintain the pumps. However, the frequency of confined space entry has decreased dramatically with the implementation of above ground controls.
“Safety and common sense are the reasons for upgrading to above grade systems,” said Girup. “Going into a confined space requires special procedures with two individuals, safety harnesses and gas monitoring equipment at a minimum to ensure safety. If precautions are not followed, consequences could be fatal.”
Village of Burr Ridge, Ill.
The Village of Burr Ridge, Ill. also called upon Metropolitan for a below ground lift station upgrade.
Metropolitan implemented an above ground traffic box for this particular project, placing all controls and electrical distribution equipment above ground.
“The customer has intentions to replace the existing pumps with submersible pumps, however, this project was phase one, which included the above grade controls to significantly reduce the amount of times they would need to go below ground,” said Girup. “In the previous configuration, the customer was going down into the pit quite often to monitor controls, but with our upgrade, they no longer have to do so.”
With each upgrade, the customer not only gained capital investment protection by implementing above grade control systems to protect controls from potential below ground flooding, they also improved safety conditions by reducing the frequency of confined space entry.
Entering a confined space is a major process with strict guidelines which, if not followed, can produce fatal consequences. Metropolitan can provide both investment protection and overall safety with above ground system retro-fit solutions.
For more information, please contact Keith Girup at 800-323-1665, ext. 264 or firstname.lastname@example.org.