Deep beneath the ground here, in more bags, barrels and boxes than the mind can imagine, the awesome triumphs of the prodigious American milk cow rest enshrined in dark, cool and costly comfort.

What they're keeping here is government-owned milk, butter and cheese. It keeps piling up, costing the treasury millions upon millions of dollars, and nobody knows what to do with it.

It makes you want to be here alone with a box of crackers and a bottle of muscatel.

This abandoned underground limestone mine, operated as the Commercial Distribution Center Inc. (CDC), is one of hundreds of places around the country where the federal government keeps its surplus milk products.

In its subterranean freezers and cooling rooms, CDC alone is storing more than 47 million pounds of dairy products that the government has had to buy from U.S. farmers through the controversial dairy price-support program.

But that's only a drop in the bucket. The Department of Agriculture now holds about 1.9 billion pounds of surplus, with only a smidgen of that committed to sales.

Uncle Sam's surplus, of course, means money in the bank for CDC. But that doesn't mean Lee A. Waller, executive vice president of the firm, is entirely happy with it.

"As a taxpayer, I hate to look at that stuff," he said the other day. "Our National Association of Refrigerated Warehousemen sent a letter to Congress saying we opposed the dairy supports."

That, however, wasn't enough to turn off the spigot, and the leftover lactose keeps flowing toward Independence and neighboring Kansas City. Mo.

This area, underlaid with millions of square feet of worked-out limestone mines that are attractive for their natural constant temperature and lower storage rates, holds more federal surplus than any other part of the country. Three other privately operated caverns under Kansas City hold 161 million pounds of dairy surpluses.

Bossy's astonishing production--and her cost to the treasury--made her one of the Reagan administration's first budget-cutting targets. It also made her one of the most controversial figures, man or beast, on Capitol Hill this year.

The farm bill passed last week by Congress will reduce dairy supports--the aim being to discourage production and cut federal costs. But even at that, the USDA expects to pay farmers about $2 billion this fiscal year for their excess production.

Agriculture Secretary John R. Block, who led the budget-cutting charge, put it this way the other day: "It is a very efficient industry and dairy farmers have done a miraculous job. It's so ironic. That's what got them in trouble."

USDA's bounteous larder here at CDC and at 600 more storage sites around the country consists of natural cheese, in barrels that weigh 500 pounds each, and processed American cheese, in five-pound loaves, six to a box. It is nonfat dry milk, in 50-pound bags that resemble cement sacks at a hardware store. And it is butter, frozen in 68-pound blocks.

This accumulation and its cost have kept the cow, the influential dairy lobby and the slam-bang debate over milk supports on front pages throughout the year. It also has engendered some nasty political back-and-forth and drawn charges that Block and the administration have "grandstanded" the issue.

On one recent occasion, Block displayed blocks of molding processed cheese at the White House to show, he said, that "we're in an acute period . . . that we don't feel we can keep the oldest cheese much longer. I did that in order to make the public realize the problem."

The mold on parade brought a reproachful riposte from Rep. Tom Harkin (D-Iowa), a leader of the dairy forces, during House debate as action on the farm bill was bringing the congressional session to a close. "Shame," he cried. "Shame on Secretary Block for bringing out moldy cheese . . . He should have shown how well fed we are in this country."

Harkin also charged that the administration has distorted the picture, with its suggestions that the cheese is going bad rapidly, and has not made wholehearted efforts to sell the surplus, just so Congress would be bludgeoned into cutting back the support program.

Block denied those accusations in an interview. But other officials at USDA concede that the spoilage threat is not as serious as some dairy critics maintain and that actual storage costs are nowhere near as high as the $1 million a day that Block and other administration supporters have claimed.

Merritt Sprague, a USDA commodity supervisor, said that about 44 million pounds of cheese (of a 625 million pound inventory) have been identified as moldy but that "our scientists assure us that the mold is harmless, although it still reduces the attractiveness."

He also said that dairy product storage and handling comes to about $42.5 million a year, although interest charges on a $2 billion inventory could lift the total daily cost to around $1 million.

Added Harkin last week: "I'd be a fool if I didn't say we have a problem, but it is nowhere nearly as calamitous as they are claiming at USDA. I think they are distorting things and purposely sitting on the surplus. We had other surpluses nearly this large in the 1960s and we were able to get rid of them."

That aside, the government still is standing on a mountain of cheese, butter and dry milk with no good ideas for unloading it without taking big financial losses.

The White House Cabinet council on food and agriculture plans to take up the question of what to do with it early this week. But for the moment, it's being cooled at places like CDC's 158-acre underground facility here at Independence.

Lee Waller and his son David, a vice president of CDC, leading a recent tour of their underground storage vaults, chuckled a bit as a visitor expressed amazement at the quantities of bagged dry milk, boxed butter and cheese.

The Wallers noted that USDA is their toughest customer, insisting on full restitution if any products are damaged, maintaining constant quality control and raising stiff challenges to any questionable billing.

The milk is unloaded from railroad cars that move into the caverns on an underground track. From there it goes onto pallets and then the bags are stacked 16 feet high, almost to the ceiling, in cool rooms with low humidity. As far as the eye can see, room to room, are stacks of bagged milk.

The butter is stored in freezer rooms at zero degrees. The barrels of natural cheese, 42 inches tall, are stacked three high. The boxes of processed cheese bricks are kept in rooms where the temperature is held a few degrees above freezing. As USDA periodically sells or disposes of the surpluses, CDC ships out quantities from the oldest stocks, making room for new goods.

The Wallers took it a little personally when they heard about Secretary Block's displaying moldy cheese at the White House. They thought it reflected on their industry's ability to keep surpluses in good condition.

"Some of us were aggravated that this guy would hold up moldy cheese," Lee Waller said. "Processed cheese will keep for five years under proper conditions."

Only one problem with that. With dairy production and government purchases continuing to rise, there may one day be no place left to keep it all.