WASHINGTON -- While the "fiscal cliff" dominated political discourse in Washington in recent weeks, some business groups and Republicans suggest the next political precipice may be a "regulatory cliff."

For months, federal agencies and the White House have sidetracked dozens of major regulations that cover everything from power plant pollution to workplace safety to a further crackdown on Wall Street.

The rules were largely put on hold during the presidential campaign as the White House sought to quiet Republican charges President Barack Obama was an overzealous regulator, killing U.S. jobs.

But since the election, the Obama administration has quietly reopened the regulations pipeline.

In recent weeks, the Environmental Protection Agency has proposed rules to update water quality guidelines for beaches and other recreational waters and deal with runoff from logging roads.

The National Highway Traffic Safety Administration has proposed long-delayed regulations requiring automakers to include event data recorders -- better known as "black boxes" -- in all new cars and light trucks beginning in 2014.

The administration also has initiated several rules to implement its health care overhaul, including a new fee to cushion the cost of covering people with pre-existing conditions.

Some GOP lawmakers fear the worst.

Obama has spent the past year "punting" on a slew of job-killing regulations that will be unleashed in his second term, says Sen. James Inhofe, R-Okla. It's now "full speed ahead" for federal rules limiting greenhouse gas emissions, requiring cleaner gasoline and putting controls on drilling for oil and natural gas, said Inhofe, the senior Republican on the Senate Environment Committee.

"Under an Obama EPA that has earned a reputation for abuse, American families will be subjected to a regulatory onslaught that will drive up energy prices, destroy millions of jobs and further weaken the economy," he wrote in a 14-page report on expected EPA regulations for 2013.

The report predicts an influx of regulations that "spell doom for jobs and economic growth."

Environmental groups say fears of a second-term regulatory deluge are overstated.

"At this point it still has the appearance of being more of a trickle than a flood," said Frank O'Donnell, president of the environmental group Clean Air Watch. "I don't see the hard evidence" of an avalanche of rules.

He said the EPA is principally focused on meeting court-ordered deadlines, such as the deadline for a rule intended to reduce the amount of soot that can be released into the air. Other high-profile rules and initiatives are being rolled out more slowly, if at all, he said.

Randy Rabinowitz, director of regulatory policy at OMB Watch, a private group that tracks federal rules, said regulations now being released are long overdue - in some cases months or even years after federal guidelines say they should have been published.

"We've been disappointed that Obama has been a tepid regulator" in his first term, Rabinowitz said, adding that she hopes the administration "moves more vigorously to protect the public from harm" in a second term.

A spokeswoman for the White House Office of Management and Budget, the gatekeeper for federal regulations, said the administration is focused on protecting public health and safety while avoiding unnecessary burdens on business.

"We intend to continue that approach moving forward, including careful analysis of costs and benefits, as well as a commitment to protecting the health, welfare and safety of the American people at the same time that we promote economic growth," OMB spokeswoman Moira Mack wrote in an email.

Economy at risk?

Some Republicans and business groups say new regulations, on top of rules already issued by the administration, could strangle the economy just as it begins to grow.

A new study by the National Association of Manufacturers claims major new EPA rules could cost manufacturers hundreds of billions of dollars and eliminate millions of American jobs.

The report, issued in late November, said compliance costs for six major EPA regulations, including rules limiting air and water pollution from coal- and oil-fired power plants, could total up to $111 billion by government estimates and up to $138 billion by industry estimates. Construction costs could total $500 billion, it said.

Jay Timmons, president and CEO of the manufacturing group, warned of a "devastating ripple effect" that could be felt throughout the U.S. economy if federal rules are not relaxed or delayed. Some manufacturers are likely to "close their doors for good" because of EPA rules, Timmons said.

Susan Dudley, director of the Regulatory Studies Center at George Washington University and the former head of a Bush administration regulatory office, said she has not seen a post-election surge in federal rule-making.

"It doesn't look like the floodgates are opening," she said, adding that with four more years in office, Obama is in no rush to implement rules that could damage a fragile economy.

The slowdown fits a pattern, Dudley said. During his first two years in office, Obama published a "record-setting" average of 63 economically significant final rules per year, she said, a pace that slowed to about 50 major rules in 2011 and fewer than two dozen last year.

Dudley said she expects a second Obama term to be more like his first two years in office than his third and fourth years - in part because so many federal rules that have been started have been put on hold.

One of the most high-profile delays was on a pledge to set stricter limits for lung-damaging smog. President George W. Bush had shunned the advice of independent scientists who said the current ozone standard was too weak.

Under Obama, the EPA had promised to change that, only to have the White House put on the brakes in September 2011, explaining it was acting to reduce regulatory burdens and uncertainty in a shaky economy. A new ozone rule is now likely to be finalized this year.

Other environmental regulations, including a rule to reduce greenhouse gas emissions from refineries and to lower the sulfur content in gasoline, are far behind schedule. EPA officials have said not to expect them anytime soon.

Closer to home

For the over-the-road bus and truck industries, much of the regulatory focus will be on the implementation of last years highway law, Moving Ahead for Progress in the 21st Century.

The $105 billion transportation funding law kick-starts 29 safety-related initiatives, including the electronic onboard recorder mandate. The law requires the Federal Motor Carrier Safety Administration to develop a final EOBR rule by October, with the rule taking effect in 2015.

However, several ground transportation lobbyists are predicting the final regulation wont be in place until late next year because of the amount of work involved in the rulemaking process. The final rule would be followed by a four- or five-year implementation process.

While Congress was able to pass a highway bill last year, the measure provided funding for only two years and contained no new revenue to help fix deteriorating roads and bridges and to fund new infrastructure projects.

The unwillingness of elected officials to increase fuel taxes raised the prospect of more toll roads or, worse, a system that assesses taxes on every mile traveled, some ground transportation officials worry.

U.S. Rep. Earl Blumenauer, D-Ore., has introduced legislation in the House that would fund a vehicle miles traveled pilot program to examine the proposed new source of funding that would help make up for the Highway Trust Fund deficit.

The legislation calls on the Secretary of the Treasury to undertake a series of studies to demonstrate the viability of a VMT revenue source in every state, and it reflects a pilot program that has been ongoing in Oregon.

"We must invest now in our nation's roads, bridges, and public transit to prevent enormous costs in the future," said Blumenauer. "With the Highway Trust Fund facing a 21 percent reduction revenue by 2040, based on current driving patterns and projected increases in fuel economy, we need innovative solutions to close this gap."

Over the past four years, Congress has transferred more than $48 billion from the General Fund into the Highway Trust Fund, Blumenauer notes. Estimates suggest that, when the current transportation authorization expires, the Trust Fund will require almost $15 billion a year in addition to current fuel tax receipts simply to maintain 2009 funding levels.

Early VMT testing

"Oregon and other states have successfully tested a vehicle miles traveled fee, and it is time to test this model systematically, across the country," Blumenauer says. "While evaluating mileage-based revenue sources, this legislation will ensure the system protects privacy and is simple to administer.

"It will also convene working groups to address the most complex aspects of this transition, including road use, demand management, climate change, and technology needs."

In Oregon, the U.S. Department of Transportation is testing three privately manufactured devices. Two use GPS technology, including a smartphone app, while a third simply counts miles.

Two blue ribbon commissions have suggested that transitioning to a VMT system, rather than a fuel tax, will provide the most stability to the Highway Trust Fund, and will most accurately reflect the user-fee concept it is based upon.

The National Surface Transportation Policy and Revenue Study Commission noted that a VMT charge is "the most promising alternative revenue measure" to the existing gas tax, while the National Surface Transportation Infrastructure Financing Commission reported that "a charge for each mile driven . . . has emerged as the consensus choice for the future."

The National Surface Transportation Infrastructure Financing Commission, which was chartered by Congress to prepare an objective, in-depth analysis of highway funding, urged Congress to begin to address the issue in last summer's highway bill.

Both commissions found that the system was efficient at raising revenue, closely linked system demand to revenues, and could win broad public support, Blumenauer says.

In March 2011, the Congressional Budget Office released a report saying such a program is a "practical option" for raising new funds. Shortly afterward, the USDOT proposed a study of the concept, but President Obama has resisted switching to a VMT fee.

Lingering concerns

Meanwhile, the trucking and bus industries continue to voice concerns about several aspects of the Federal Motor Carrier Safety Administrations Compliance, Safety, Accountability program, including a plan to delay the implementation of a program that would assess responsibility for accidents when considering penalties involving carriers Behavior Analysis and Safety Improvement Categories scores.

Armed with studies that showed CSA scores didnt accurately predict crash risk, the trucking industry convinced lawmakers on Capitol Hill that BASIC alterations were needed, and FMCSA made "modest" changes to the program.

Truckers expect prioritization of truck and bus safety rulemakings to be driven by the Obama administrations "overarching political agenda to champion labor issues and consumer protections."

Truckers expect a push to raise minimum insurance levels and more enforcement actions against carrier executives with a pattern of safety violations.

Driver pay and health and wellness issues, including problems such as sleep apnea, also could be the focus of more regulatory activity.