Mandatory fuel conservation measures in Virginia are responsible for layoffs of more than 5,000 workers in two days, the Virginian Employment Commission reported yesterday.

The layoffs occurred in the wake of Gov. Mills E. Godwin's order Saturday limiting retail businesses to a 40 hour week until Feb. 14. Godwin's order, by far the most stringent measure taken for any of the jurisdictions in the Washington metropolitan area, has increased unemployment in a state where some 30,000 to 40,000 workers already are unemployed because of the severe weather and natural gas curtailments.

In Northern Virginia alone, according to a spokesman for the Heavy Construction Contractors Association, about 3,000 workers have been laid off because of frozen ground 18 to 36 inches deep. "You just can't excavate," the spokesman said. The ground normally is frozen to 6 inches at this time of year, a crust thin enough to be broken by trench diggers and bulldozers.

As a result of the weather, all groundbreaking has been halted, association administration director Terry Cook said yesterday.

Maryland officials estimate that 10,000 workers would be laid off because of natural gas cutoffs, in addition to 63,000 to 68,000 workers already unemployed for other reasons.

An official of the Washington Gas Light Company said yesterday that the area's supplies "are in good shape," but that the most critical period is the next two or three weeks. Another severe cold snap, WGL vice president Donald J. Heim said, would mean that "the situation we now find ourselves in could well occur again."

Heim, testifying at a hearing of the District of Columbia Public Service Commission, said gas users in the Washington metropolitan area have "cooperated in an excellent fashion" in reducing their consumption during the present emergency.

The Baltimore Gas and Electric Company, the supplier of gas to the greater Baltimore area, reported an "excellent" reduction of 10 per cent since curtailment measures were instituted Friday.

At the same time, however, an official of the Columbia Gas Transmission Corp. - the major supplier to both Washington Gas Light and to BG & E raised a new warning. With warming trends expected for the rest of the week - local forecasts call for temperatures in the 30s and 40s during the day - gas users may think the problem is over.

"Conservation is as important on a day when the temperature is 30 as it is on bitter cold days," said Thomas L. Ryan, public relations director of Columbia Gas.

A Washington Gas Light spokesman said last night that Columbia Gas Transmission Corp. had just informed its customers that the curtailment in gas supplied through the pipeline had been extended from Feb. 5 until Feb. 9.

The curtailment, which means that local restrictions will almost definitely have to continue, results from colder than normal weather predictions for other regions served by Columbia Gas. The pipeline company also serves Ohio, Pennsylvania and West Virginia.

The D. C. Public Service Commission yesterday approved an extension to fits order to gas users to curtail consumption until Saturday. That action, taken before the new curtailment order from Columbia, now will have to be reviewed.

Gov. Godwin's executive order was a discussion topic in both Maryland and the District of Columbia yesterday.

During his testimony before the D. C. Public Service Commission, Heim was asked about Godwin's order.

"We do not anticipate requesting that type of action in the District or in Maryland," Heim said, adding that the type of action requested by Washington Gas Light on Friday - cutting nonessential commercial comsumption to the bare minimum needed to keep pipes from freezing or to the lowest thermostat reading and reducing essential users to 65 degrees during the day and 55 at night - appeared to be sufficient.

Heim said that the District, Maryland and Virginia were all asked by Washington Gas Light to do the same thing. Godwin, Heim said, " was attempting to expand the request for conservation" to oil as well as gas, " and he chose that vehicle to do it . . . Obviously, we have no control over the governor of a state," Heim said.

Heim said at another point in the hearing that Washington Gas Light has not asked any customer to stop operating. The gas company has asked certain customers to severely curtail use, he siad. "If a customer chooses to operate his business under those conditions, we certainly have no objection," Heim said.

Maryland Gov. Marvin Mandel said in an interview yesterday that he had resisted suggested from private citizens that state employers shift to a four-day work week, that schools be closed and even that the National Guard be called out.

"But why?" shrugged Mandel. "None of that is necessary." Mandel said he was not critical of Godwin's actions because "I don't know what the problems are in Virginia. But I do know about Marylands." More stringent controls might result not only in panic but in excess profits for some businesses, Mandel said.

Although much of the work reduction in Virginia is occurring in the northern part of the state in stores and shopping centers that use only electricity, the State Corporation Commission estimated that peak power demand on the Virginia & Electric Power Co. system on Monday was only about 5 per cent below normal for the prevailing conditions.

Peak demand during the morning and evening period of maximun usage was about 6,400 megrawatts. A megawatt is 1,000 kilowatts - about enough to operate 50 home furnances simulataneously.

Vepco's power reserve for the day was about 31 per cent, approximately twice the reserve recommended by state and federal regulatory agencies.

James Wittine of the State Corporation Commission said that the lower power demand is a result of reduced industrial operations caused by natural gas curtailments and of reduced retail establishment operating hours. He said he cannot estimate how much of the cutback can be attributed to the retail stores' reduced hours.

After questions were raised about the necessity of rationing electricity used by retailers, Godwin asked SCC utility specialists to determine the impact of the orders on oil consumption by Vepco and other electric companies.

Wittin said he told the governor yesterday tha the orders are justified because Vepco uses heating oil to operate generating equipment used to meet peak demands. He said he could not estimate how many gallons of fuel might be saved, however, or whether Vepco sayings will result in fuel transfers to other users.

The overall fuel oil suppy in Virginia remained, in the words of one major distributor, "nip and tuck." Pipeline officials, major oil company supply specialists and Virginia distributors sad in interviews that major storage facilities in the state are occasionally completely out of oil. They said, however, that there have been no reports that residential or business customers are out or oil.

Like the electric utility regulators, the fuel oil specialists could not estimate how much oil is being saved by cutting back business hours. "There is a woeful lack of information on who uses what amount of fuel," said Ralph Roop, president of Petroleum Marketers, Inc., of Richmond, one of the state's largest fuel oil distributors.

Official actions taken in Maryland, Virginia and D. C. widely vary.

In the District, according to Corporation Counsel John R. Risher, the mayor has no emergency powers in the current situation and hence, has issued no orders, Mayor Walter E. Washington has asked businesses and private citizens to lower fuel consumption.

The District Public Service Commission ordered nonessential commercial gas users to cut consumption to the bare minimun and requested private home owners and apartment buildings to lower comsumption.

In Maryland, the governor's excutive order issued Monday requires thermostats cut back to 65 degrees in working areas in all buildings used by the state, counties and municipalities.

The Maryland Public Service Commission was granted authority to allow gas companies to suspend delivery to large customers that fail to curtail use.

A civil penalty of $1,000 may be imposed for each violation.

Godwin's order in Virginia generally limits all retail business and services to 40 hours of operation a week with thermostats set at a maximum temperatuure of 65 degrees.