WASHINGTON (AP) -- Farmers and factory owners who illegally hire underage children generally get away with it.

The U.S. Department of Labor, charged with enforcing the nation's child labor laws:

--Fails to find the most vulnerable victims of child labor.

--Maintains a secret fine schedule that undercuts the $10,000-per-violation child-labor penalty imposed by Congress.

--Fails to bring criminal cases against repeat offenders.

--Does not seize goods that are the product of illegal child labor, as provided by law.

These are among the findings of a five-month Associated Press investigation of child labor in America.

U.S. Labor Secretary Alexis Herman did not dispute them. ``It's not acceptable for employers to think they can skirt the law, that the Department of Labor is not serious about enforcing the law,'' she said. ``And I am on a path of making sure that we are more aggressive on that front.''

Last year, at least 290,200 minors worked illegally in the United States, according to an AP analysis that used the government's own statistics. Labor Department investigators found 6,735 child labor violations at 1,546 establishments.

One-fourth of those establishments were fast-food restaurants, department records show. The typical violation the department uncovers is a high school student working later than the law allows on school nights.

The children the department does not find are the most vulnerable ones -- the very young, the illegal immigrants, the impoverished children who work not just to get extra spending money but to help feed their families.

The AP found many such children working illegally in dozens of fields and factories from coast to coast. Yet Labor Department officials around the country say those children are nearly impossible to find.

"I don't believe we have ever found it,'' said Jorge Rivero, Labor Department district director in Miami. ``If it exists, we don't know about it.''

Less than an hour away, however, near Homestead, Fla., the AP found eight underage children harvesting beans on several farms on a single day in November.

The Labor Department can overlook children working illegally even when someone else has found them and put it in writing.

In Brewster, Wash., more than 100 workers at a cherry- and apple-packing plant suffered carbon monoxide poisoning in July. Hospital records, which appear in the state's investigative files on the incident, show that seven of the victims were under 16.

The plant's president, in an interview, freely acknowledged these children had worked illegally at the plant and that he had fired them after the incident.

Yet federal investigators in Seattle said they knew nothing about the matter.

Maria Echaveste, an assistant to President Clinton, said it's easy -- and unfair -- to say the government doesn't care about children who work.

Ms. Echaveste, who picked strawberries as a child in California and who, until February, headed the Labor Department division responsible for enforcing child labor laws, said enforcement has historically been a low priority. She said tight budgets and bureaucratic inertia make reversing priorities difficult.

Former Labor Secretary Robert B. Reich agreed. "Remember there are only 800 federal inspectors'' for millions of workplaces, he said in an interview. "If we had more resources, they could do far more.''

This year, the number of inspectors was increased to 942.

The last major federal campaign against child labor came in 1990, when Labor Secretary Elizabeth Dole led Operation Child Watch. It found 28,000 minors working in violation of federal labor laws and assessed more than $6 million in fines. Only about one-fourth of that was ever collected.

However, there is no evidence the campaign changed anything in the long run. And no administration, including Clinton's, has done anything like it since.

Soon, Ms. Herman said, the government will try again. Operation Salad Bowl, she announced, will be launched next spring. The initiative, she said, will involve 50 farm inspections, concentrating on lettuce, tomato, garlic, onion and cucumber fields around the country.

Ms. Herman said she and Secretary of Agriculture Dan Glickman "have now made a commitment to go out into the fields in the first quarter of 1998 to engage this issue head on and hopefully try to deal firsthand with some of the things you have uncovered here.''

If Ms. Echaveste's experience is a guide, Ms. Herman will have some obstacles to overcome. Ms. Echaveste said she met with resistance when she tried to get investigators into the fields to look for kids.

"Where would you rather be?'' she asked a reporter. ``In a nice air-conditioned office and interview some accountant and look at their records, or would you rather go out in a field at five in the morning to see who's working?''

She said she also had to contend with inspectors who simply took the word of farmers who claimed they didn't employ children.

"I've never seen anyone working on any farm anywhere who is under the age of 18,'' said Brian Little, director of governmental relations at the American Farm Bureau Federation, a large lobbying group.

"See?'' Ms. Echaveste said when told of the remark. "They actually say that!''

Even when the Labor Department does find violations, it usually doesn't do much about it.

According to the law, employers who hire children illegally are at the very least supposed to be fined. In 1990, Congress decided the fines weren't high enough and raised the maximum penalty from $1,000 per violation to $10,000.

Congress directed the department to use discretion in setting fines -- to consider the size of the business and the employer's familiarity with the law.

The practical result: The average fine assessed by the department increased from $212 in 1990 to $887 last year -- nowhere near the maximum set by law.

A ``Child Labor Civil Money Penalty Report,'' which the department tried to withhold but the AP obtained, may explain why.

The secret report is used by compliance officers to set fines -- fines almost always discounted significantly from the recommended maximum set by Congress.

Among the reduced fines:

--$275 for poor record-keeping.

--$500 for a farmer who employs a 12- or 13-year-old during school hours.

--$600 for the same violation at other businesses.

--Fines are reduced 30 percent for businesses with 20 or fewer employees.

The maximum fine, $10,000, is used only when a child working illegally is seriously injured or killed. Other fines are far lower, despite congressional intent to use the maximum fine as a deterrent.

The schedule is the work of mid-level Labor Department administrators. Top administrators professed to know little about what it said.

"That couldn't be right,'' Corlis Sellers, a program administrator, said when told the sheet gives farmers a $100 break over other employers.

Then she took a closer look.

"There's a $100 difference,'' she said quietly. Asked why, she seemed puzzled. ``I don't know, off the top of my head.''

Ms. Herman said she was unaware of the fine schedule until the AP inquired about it. She said she was concerned both by the difference between industry and agriculture and by the low amounts of the fines it recommends.

"Just on the face of it, after consultation with our legal team, it looked inappropriate and it was not clear to me there was justification,'' she said. ``I intend to act on it.''

Late last week, Ms. Herman's staff had begun to order changes in the fine schedule.

In addition to civil fines, the law allows repeat offenders of child labor laws to be charged with criminal misdemeanors. Penalties include up to six months' imprisonment for a second conviction.

But no one has gone to jail for federal child labor violations in seven years. Generally, it happens about once a decade.

One reason: The Labor Department doesn't seem to know which law breakers are repeat offenders.

Labor Department spokeswoman Rae Glass said investigators are supposed to check department computer files to see if an employer has been in trouble before.

However, many district offices don't have access to the computer files. And even if they did, the files often wouldn't tell them much.

Names of violators are often misspelled or entered in slightly different ways. For example, McDonald's shows up as McDonald's, McDonalds, Mc Donalds, MacDonald's, McDonald's Restaurant and more. As a result, a multiple violator can appear to be a string of single violators. A McDonald's spokeswoman said the corporation abides by federal and state child labor laws and requires franchisees to do the same.

When the AP searched the database using variations in spacing, punctuation and spelling, it found 129 different recurring violators for last year alone.

Not one was prosecuted as such.

Perhaps the toughest enforcement tool available to the Labor Department is the ``hot goods'' provision. This 60-year-old clause allows authorities to seize products that are made with illegal child labor.

Under this law, the taint of such labor stays with a dress from the moment a child trims its threads in a New York City sweatshop until it enters a department store. The taint stays on a cucumber from the moment a child picks it in Ohio to the day it sits in a jar of pickles inside a supermarket warehouse.

Furthermore, if that cucumber is tossed in with a large batch of other cucumbers picked by adults, the entire batch is subject to seizure as hot goods.

In Dallas, the Labor Department's regional administrator, M. J. Villarreal, said seizing goods to discourage illegal child labor ``is a goal of ours.''

But the department rarely gets around to seizing anything; some department officials seem unaware that they can. Ms. Herman said she has asked department lawyers to look into using the hot goods law.

Ms. Echaveste recalled arguing the point with Labor Department lawyers, who would tell her: ``You can't use hot goods on manufacturers, or even retailers.''

"I literally took the law and read it to them,'' she said.

She is "still waiting'' for someone to use it.