Security, safety standards key inside Grand Gulf

Published 12:00 am Sunday, August 5, 2001

PORT GIBSON – Visitors get an up-close look at the rigid safety and security standards at Grand Gulf Nuclear Station. Queries, paperwork, radiation scanners, protective suits, badges, goggles, earplugs and many heavy locked doors stand between the outsider guest and the inside of the plant. Evidence of security measures enforced even among seasoned employees is evident, as well.

At the main entrance to the large auxiliary building, Vincent Bonds of Natchez checks in visitors, passing out papers to sign and white plastic-like suits for them to don, all the while explaining the process. A health physics technician, Bonds and those who work in his department monitor the radiation doses of every employee working in the plant. Behind a counter, the health techs move about busily, surrounded by expansive control panels and radiation-savvy check points, where machines with unnerving warning blasts, announce any out-of-the-ordinary finding on person or thing.

Bonds demonstrated the small individual monitors worn by visitors and workers alike, showing its zero reading for millirems, the measurement used for keeping track of a person’s exposure to radiation. Upon return to the checkpoint after the plant tour, Bonds placed each monitor in a machine to check for any change in the radiation level.

The Nuclear Regulatory Commission has strict standards to keep radiation exposure to a minimum for workers at plants such as Grand Gulf. The annual limit for employees is 5,000 millirem of radiation a year. For the general public, the annual limit is no more than 500 millirem a year from the operation of the nuclear plant. Entergy Corporation, which owns and operates Grand Gulf, 37 miles north of Natchez as well as River Bend Nuclear Station at St. Francisville, about 70 miles to the south of Natchez, has imposed even stricter limits on itself, committing to a limit of no more than 25 millirem a year.

Each year, the average American is exposed to about 180 millirem from natural and man-made sources, Entergy sources say. &uot;Someone living near a nuclear plant receives approximately one more millirem of radiation per year, which is about the same amount of additional radiation received by wearing a wristwatch with a luminous dial,&uot; an Entergy pamphlet points out.

Creating energy, waste

An immaculately kept plant, the innards of which are a mass of pipes, tanks and gauges painted mostly bright colors of yellow, green and blue, Grand Gulf, like all the other 102 nuclear plants in the United States, continues to store all its nuclear waste on site.

The concrete, stainless steel-lined pool where the waste rests is remarkably unremarkable in appearance, resembling an average-size swimming pool, though much deeper and with water that is dark blue and opaque. Yet, to the untrained eye of a visitor, the pool has an eeriness about it if only because one cannot help thinking of the potent matter contained there.

Joe Czaika, Grand Gulf nuclear specialist, emphasized the careful inventory kept and expert handling of fuel assembles in the pool. Spent fuel and new assemblies are submerged in the pool, the ones awaiting an expected transfer to a permanent storage site in the future and the other awaiting movement into the core after it has been thoroughly checked into the plant by specialists.

Grand Gulf uses uranium as its reactor fuel. The fuel is refined and shaped into pellets about half an inch in diameter. The fuel pellets are sealed in 12-foot hollow tubes called fuel rods. The rods, placed in a way to allow a liquid coolant to flow between them, are grouped as bundles known as fuel assemblies.

During the heat-creating nuclear fission process, water continuously circulates around the fuel rods, boils into steam, is set through the blades of the turbine and then is cooled to become water again. The water then is pumped back into the reactor vessel for a repeat of the process.

In a separate system, cooling water carries away the heat. That water never mixes with the water that circulates through the reactor, said nuclear specialist Czaika. The vapor emissions from the cooling tower are pure, clean steam.

Waste bundles in the pool inside the plant will remain there until approximately 2006, said Jill Smith, communications specialist. &uot;After that they will go into dry-cask storage,&uot; she said. &uot;Our Arkansas plant already has gone to dry cask and River Bend will go to dry cask in about 2003.&uot; Entergy’s nuclear plants in the South include, in addition to Grand Gulf and River Bend, a plant at Russellville, Ark., and one at Taft, La., near New Orleans.

About every 18 months, a nuclear plant shuts down for refueling. Grand Gulf had its last refueling process in April, and employees proudly tout the efficiency with which the most recent refueling took place. &uot;This was the shortest refueling outage in our history,&uot; Smith said. &uot;We were shut down for 21 days, 17 hours and 40 minutes.&uot;

During refueling, maintenance chores also are done, with as many as 1,000 additional workers such as welders and painters coming into the complex to help with the intensive schedule of activities. Like all workers at the plant, the seasonal workers who come in during the refueling period also go through company training, Smith said.

&uot;This also was the safest refueling outage we’ve ever conducted,&uot; plant manager Venable said. &uot;Other companies come here to see what we do. We have become kind of a benchmark in the industry.&uot;

Heart of the plant

Deep inside the nuclear station complex is the heart of the operations, the control room where technicians and engineers monitor production of electricity and the transmission of it – 1,300 megawatts a day – to a grid that goes all the way to New York, said plant manager Joe Venable.

&uot;Our company is using and selling locally and selling power to other companies,&uot; he said. Grand Gulf, in fact, is the largest nuclear plant of its kind in the United States.

J.D. Weeks of Natchez is one of the control-room operators. Red and green lights glow around the panel-lined room. Gauges flicker and monitors reveal information that shows the plant’s daily routine is just that – routine.

&uot;From the control room, the operators know what is going on throughout the plant 24 hours a day, seven days a week, 365 days of the year.&uot; communications specialist Smith said. &uot;There are hundreds and hundreds of indicator windows, and they know what each one means and how to react to each one.&uot;

Training for a control-room position is similar to a tough college program, she said. &uot;They go through rigorous training.&uot;

Roger Butler agreed, as he explained the range of work taking place in the spacious, quiet, highly organized room. &uot;We have workers in here representing everything from a high school education to an engineering degree,&uot; Butler said. &uot;But it takes two years to go through the program.&uot;

Encouraging young people to go into the field of nuclear engineering is one of the industry’s biggest challenges, Venable said. Universities are trimming their nuclear science courses in reaction to flagging interest in the area.

With interest growing once again in nuclear power, Venable hopes the trend will be reversed. Meantime, his company courts bright young college students who are in other fields.

&uot;We talk with universities and bring co-op students into the plant and let them see what’s going on,&uot; he said. &uot;Now if the public becomes more aware of the growth of the industry, more students will become interested.&uot;