Safety – Equipment & Systems: Green Country Energy – Combined Cycle Journal

Safety – Equipment & Systems: Green Country Energy

Tornado shelters safeguard most valuable assets

Green Country Energy
Owned by J-Power USA, Operated by NAES Corp
800-MW, gas-fired, 3 × 1 combined-cycle located in Jenks, Okla
Plant manager: Rick Shackelford
Key project participants: Linne Rollins, Dave Rose, Carol Wilson, Danny Parish, Phil Pace, Allen Meyer, and Chris Shipman, Green Country safety committee members


Oklahoma is typically known for rodeo cowboys, college football, and unfortunately. . .tornados. The state averages 54 tornados per year but has seen activity as high as 145 in 1999. Unfortunately, mobile home parks and powerplants appear to be subjected to more than their fair share of tornado attacks. For example, in years past, significant tornado damage occurred at plants in Muskogee, Anadarko, and Woodward.Plants in Tornado Alley have emergency procedures that are employed during a tornado threat. However, offering plant employees a safe shelter during a tornado threat presents some real challenges at newer combined cycles, where most buildings are of corrugated metal siding construction and lack basements. Green Country’s goal is provide the staff with reliable shelter when one of the strongest forces of nature threatens their safety.


The value of storm shelters was never more apparent than in 2004 at the Parsons Co manufacturing plant in Roanoke, Ill, when an F4 tornado obliterated the site (Fig 35). Over 100 workers at the plant during the event remained safe and only minor injuries were sustained. The aftermath of the tornado and locations of the three storm shelters are seen in Fig 36.Upon learning of and discussing the Parsons Co’s remarkable safety accomplishment during an F4 tornado event, our safety committee, plant management, and owners decided to purchase and install tornado shelters at various locations throughout the plant.

As shown on the Figs 37 and 38, a 14-person tornado shelter was installed at a central location within the plant (just outside of the Unit 2 electrical equipment room) and a 24-person shelter was installed behind the combined admin building/maintenance shop.Careful consideration was made to the proximity of high-voltage power lines, and high-pressure piping when identifying the best location for shelter placement.

The shelters selected were constructed locally and designed to withstand an F5 tornado and can support over 100,000 lb stacked on top of them, which is equal to about 25 mid-sized cars.In addition to shelter installation, storm spotter training DVDs were purchased, watched, and discussed during weekly safety meetings. Emergency procedures were also improved to include recommended actions during scheduled maintenance outages, with consideration to a number of contractors who might be onsite during a storm.

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Fortunately, the tornado shelters have not been needed since their installation and the plant staff is obviously hopeful they will never be used. However, they certainly provide a significant peace of mind when tornadic storms are in the vicinity of the plant. And, should a tornado ever find its way to the plant, the decision to equip the plant with tornado shelters would undoubtedly be the best decision ever made at this Oklahoma powerplant.

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