In just a few days they will come, swarming like locusts through the Montgomery County fairgrounds in search of fun, entertainment and old friends. Without fail, they will all be hungry. But the woman in charge of seeing to it that visitors to the fair get the hot meals they always look for is calm.

Ruth Benneth sits in the dining room of her Laytonsville home, ticking off the items on her grocery list that will feed the 6,000 people - give or take a few hundred - who will be eating in the dining room during the six-day Montgomery County fair, which starts Aug. 22 in Gaithersburg.

The 450 dozen ears of corn will be there, of course. Tom Kelley, who lives in Darnestown grows a whole field of corn to be used at the fair each year, and this year will be no exception. Then there's 1,200 chickens, 900 pounds of coleslaw, 1,260 eggs, 1,500 pounds of potatoes, 300 pounds of roast beef, 180 pounds of bacon, 800 or so rolls, the makings for 62 gallons of homemade mayonnaise and much, much more.

If it's very hot during fair week, which goes by no other name in the rolling hills which blend the old farm houses and new developments surrounding the fairground, 600 gallons of iced teas might not do it. Bennett's son, Doug, guesses that the two 55-gallon wooden barrels that hold the teas might need filing twice a day. And they have sure that the 105 50-pound bags of ice it takes to keep it cold show up on time.

It's practice, Ruth Bennett says, that makes her calm. From September through June for the past five years she has been a Montgomery County school cook, in addition to overseeing the running of the main dining room for her parish, St. Paul's United Methodist Church in Laytonsville, since 1968.

"If you have people who know their jobs and do it almost professionally, then you don't have to worry," she says. With such people, Bennett says, they are blessed. "Some people at the church have been helping for three or four generations."

Montgomery County policeman Charles (Pete) Ayton is one of 300 volunteers who will help with the dining room this year. For the past five or six years he has spent a week's vacation cooking corn at the fair with his wife, Zondra. "We have a good time," he says, and the dining room is their major effort to support St. Paul's Church. Last year the church netted $10,000 after expenses were covered.

"It's not like it used to be years ago," Ayton said. "There wasn't much activity in the towns, and people didn't mind a little bit of work" a few times each year to raise money for their church. Now they are busier, and Ayton and Bennett say that most people who attend St. Paul's are glad to put forth the energy one week each year to help their church with its only money-making effort.

"Unless you've been involved in the fair," Bennett said, ". . . people just don't understand," why workers volunteer generation after generation for six long days of hard work. There are the special things, like the week-long friends you only get a chance to see at the fair. "We have some farmers who've been coming in as long as I've been there for three meals a day," she says. A hog farmer who regularly eats in the dining room at the fair told Bennett, "I always know I'm home," when he sees the familiar faces.

There are also the surprises, she said. "Last year a man came to the door and said, 'Can you use cucumbers?' and the next thing you know we had six bushels. I haven't found out who he is yet."

Other churches are also involved in the massive task to feeding the hungry fairgoers. This year, crab cakes, hot and cold submarine sandwiches, pizza and other quick lunch food will be offered in booths run by the Church of the Bretheren in Gaithersburg, Salem United Methodist Church in Clarksburg, Fairhaven United Methodist Church in Rockville, Ascension Episcopal Church in Gaithersburg and Wesley Grove United Methodist Church in Gaithersburg.

Every day the air-conditioned red brick dining room, which is on the main drag of the fairground, just past the entrance at 16 Chestnut St. in Gaithersburg, opens for breakfast from 6 to 8:30 a.m. "Then we breathe," Mrs. Bennett says, before reopening for lunch from 11 a.m. to 2 p.m. "Then we try to breathe again" before dinner, she said, which runs from 4 to 8 p.m.

Breakfast in the dining room is a hearty affair, with orange juice, coffee, hot cakes, scrambled eggs, cereal, bacon or sausage, and hash browns, which goes for $1.50 for adults and 75 cents for children. "They can have all they want," Bennett says, but it is "very seldom" that anyone is hungry enough to make another trip through the serving line.

The lunch and dinner menus are the same, with fried chicken and ham and homemade potato salad served daily. In addition, there will be veal on Wednesday, roast beef on Thursday, and a Friday, the traditional homemade crab cakes. "The same ladies have been making those for I don't know how many years," Bennett says. "They're real crab cakes - not full of bread and stuff."

After customers go through a serving line and choose meat and two vegetables, they walk to tables laden with hot rolls, tomatoes, pickles, cucumbers, applesauce and coleslaw. Lunch and dinner cost $4 for adults and $2 for children. "Lately, a lot of the younger ones have come in who are vegetarians and we try to accommodate them," she says.

But all that is yet to come, and standing on the quiet grounds where the empty white stalls stand like skeletons, she says, "There's not much to see now, but you won't find anyone home the week of the fair."