The average cow on Cecil Lomax' dairy farm here produces about 15,000 pounds of milk a year and about 24,000 pounds of manure.

The milk is antiseptically handled, stored in stanless steel tanks and sold to eager buyers.

The manure is not.

And with 220 Holstein cows, the manure - 5,280,000 pounds per year - can pile up.

For a dairy farmer like the 50-year-old Lomax, this mass is clearly a nuisance.

Dairy cows lead a relatively pampered life, eating, sleeping and being milked twice a day under a roof and on a concretefloor. They seldom go outdoors.

Lomax has lived on his 47-acre Fauquier County farm all his life and every morning for most of those years the manure had to be scraped out of the barn, loaded on a spreader and dispersed across his fields and in bitter weather the spreader could freeze up and "It is not the best peice of equipment to be working on when its full of manure," Lomax said.

Water used to wash down the milking parlor and the barn ran off into nearby streams and if the manure couldn't be spread for a few days the atmosphere ripened. "It didn't help friendly relations with the neighbors," Lomax said.

Environmental laws were tightened, the State Water Control Board paid a call and Lomax was told he would have to do something.

The step Lomax chose to take to get out of the manure problem was expensive, economically experimental and highly regarded by environmentalists. It is an example of the sort of system that more and more dairy and feedlot operators acorss the country likely will have to go to as a pollution controls are strengthened.

At one side of his cow pen, there is now a rectangular, four-by-two-foot hole into which manure is scraped every morning. A pump churns the truck through a pipe down a hill and into an open 300,000-gallon tank. Water from the barn flows by gravity into another tank and is then pumped into the big tank in enough volume to keep the manure in a semiliquid slurry that can be sprayed on his field as fertilizer. The total outlay was about $45,000.

Farmland in the Washington area and across the nation increasingly is being encroached on by spreading suburbs and the two must exist side by side. And as populations grow and water supplies become critical, the need to solve problems of agricultural runoff becomes more pressing.

If the system Lomax is using proves to be financially sound, as Lomax believes it is, it could become a business in itself with fertilizer as the product. Since Lomax installed his tank two years ago, two other Fauquier farmers have followed suit, and the system is being marketed nationally.

"I think it will pay off as well as any piece of equipment I've got," Lomax said.

"It has cut our cleanup time by about an hour and a half for three men and can spread it when we want to, not when we have to," he said.

The slurry forms a nitrogen-rich natural fertilizer and 220 cows provide enough for about 100 acres, Lomax said. Raw manure spread daily is leeched and bleached by sun and rain, but the slurry forms a dark coating that fertilizes and acts as a mulch to hold moisture in the ground.

As a result, Lomax got 100 bushels of corn to the acre last year on land that got only 1.6 inches of rain during the growing season and expects to get at least 100 bushels again this year despite the region's drought. Corn fertilized with conventional chemical substances is so poor this year that it is not worth selling and will be cut for silage, Lomax said.

And Lomax estimates that it costs $125 to raise an acre of corn under traditional methods but only about $40 a year using the manure slurry. That comes to a saving of about $8,000, not counting time saved and handling convenience, enough to make the operation economically viable, Lomax said.

The tank can hold about three months supply of manure, so Lomax has plenty of leeway to decide what he wants to do with the slurry and when.

Fortunately for Lomax and the owners of the exurban houses being built on what used to be the farm across the road, the manure slurry develops a solid crust on top and is virtually odorless.

When Lomax is ready to use his slurry as fertilizer, the crust must be broken up and "that's when all the neighbors wish they were back in the city," Lomax said. "It'll lift you right off the groun for awhile. I've though about putting up a sign on the road that says 'Smell Before You Buy.'

"But after a day we don't notice it anymore," Lomax said.