THE ENVIRONMENTAL Protection Agency wants a consultant to review its guidelines for environmental-impact statements for nuclear power plants. The Department of Transportation wants a consultant to determine how better to spur employers to promote carpooling. Recently, several federal agencies hired consultants to rewrite their nearly impenetrable regulations in plain English. These are just a few examples of the literally thousands of tasks performed for federal agencies by consultants, who during the past two decades have become a ubiquitous and integral part of the federal structure. But, incredibly, according to a recent government, at what cost, and for what purposes."

The conclusion of the Government Accounting Office study, dismaying as it is, comes as no surprise. Last summer a congressional subcommittee, after a year-long investigation, reached the same conclusion. According to both reports, the way consultants are hired is extremely loose, confused by varying and often conflicting regulations of different agencies and subject to little or no comprehensive review by a single authority. In fact, there isn't even a government-wide definition of what consultant services are. It has been estimated that government agencies last year spent $1.3 billion for consultant services. Some think that figure is a very conservation guess.

Fortunately, President Carter is lending a hand to congressional efforts - namely those of the Senate subcommittee on reports, accounting, and management - to get a handle on the consultant business. The Office of Management and Budget is trying to work out some guidelines that would propose a definition of consultant services for all federal agencies, set out the government's policy on the use of consultant services and create management controls that OMB officials claim will largely eliminate abuses of the consultant-agency relationship. Federal officials also are planning two separate data-gathering systems to keep track of government consultants hired by contract and by individual appointment.

There may be, as some critics allege, flaws and gaps in these proposals; we'll have a better measure of their value in several months. But they do show, finally, movement toward imposing some order on the farming-out of government business to private consultants.