Enlarge / Even though this stream bed is dry much of the year, it still may qualify for regulation under the Clean Water Act. (credit: Wild Horizon / Getty Images )

The latest legal decision in a years-long fight over how to implement the Clean Water Act has set rules back to where they were in the 1980s. The reversion is the product of the Trump Administration's haste to get rid of Obama-era regulations, leading to action that produced rules running counter to the Environmental Protection Agency's own scientific findings. As a result, a judge has decided that the rules cannot remain in place for the time that will be needed for the Biden Administration to formulate replacements.

Defining water

The long-running saga is the product of the Clean Water Act's remarkably vague protections. The act seeks to control pollution via a permitting process that applies to the “waters of the United States," but it doesn't define what constitutes said waters.

While the process would clearly apply to a flowing river, it's less clear whether the act would regulate the pollution of a stream bed only filled seasonally or following heavy rains—even though the stream bed can flow directly into a river that is active year-round. Similar issues apply to items like man-made ponds that connect to other bodies via groundwater flow.

Enlarge / The average car or light truck on US roads is 11.8 years old. (credit: Harvey Schwartz | Getty Images )

The last few years have seen a rather bitter fight over vehicle pollution between the federal government and California, with automakers taking sides. In August 2012, during the Obama administration, the US Environmental Protection Agency announced new standards aiming to reach a target of 54.4mpg (4.3l/100km). But with the change of administration at the beginning of 2017 came a change in those priorities.

At the time, I described the new target as "pathetic." But here's the truly scary thing—as unambitious as it was, it would still represent a 50 percent increase in efficiency compared to the existing US light vehicle fleet. According to a new analysis at Green Car Congress , if you analyze the average miles driven per gallon of fuel each year, the US has made almost no progress between 2008-2019.

The Environmental Protection Agency versus California

Shortly after the beginning of the Trump administration, the EPA gave notice that it was less interested in cleaning up vehicle emissions . Additionally, the EPA called out California , which has a waiver that gives its California Air Resources Board the power to regulate air pollution from vehicles within the state's borders. (Colorado, Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Rhode Island, Vermont, and Washington also participate in the so-called Zero Emissions Vehicle program, taking their lead from CARB.)

Enlarge / BARATARIA BAY, Lousiana - JULY 14: A young seagull rests on a boom used to contain the oil spill July 14, 2010. In the future, should this bird be killed by the oil, nobody could be held responsible. (credit: Mario Tama / Getty Images )

With the days counting down to the inauguration of President-elect Joe Biden, the Trump administration has been undertaking a series of actions that will make it more difficult for its replacements to reverse any of its policies or pursue new ones. This is especially true in the area of environmental regulations, where both the Environmental Protection Agency and the Department of Interior have recently issued decisions.

Over the last few days, Interior has issued new rules that will allow industries to kill migratory birds with impunity, and the department has moved ahead with plans to lease portions of the Arctic National Wildlife Refuge for drilling tomorrow. Meanwhile, the EPA has finally pushed through a new rule that could severely limit the ability of the agency to establish future regulations. The only small bit of consolation is that the EPA's final rule is less awful than some earlier drafts.

Only the science we like

The EPA's new rule , which will be formally published tomorrow, is an attempt to set additional standards for the evidence it considers when establishing new regulations for pollutants. In principle, the rule sounds great: it wants the data behind the scientific papers it uses to be made publicly available before it can be used to support regulatory decisions. In reality, the rule is problematic, because many of these studies rely on patient records that need to be kept confidential. In other cases, the organizations with the best information on some environmental hazards are the companies that produce or work with them, and they may not be interested in sharing proprietary data.

Enlarge / A thoughtful soul decides to poison the air as he drives through the infield at Daytona International Raceway during the 2016 Rolex 24 race. (credit: Jonathan Gitlin)

I remember the first time someone rolled coal on me. It was 2006, and I was driving to work at the University of Kentucky. It was a bright, sunny day in Lexington, and I had the roof down and was stopped in traffic behind a large pickup truck with decidedly non-standard exhaust pipes exiting straight up behind the cab. Whoever was driving the pickup evidently noticed the Miata in his mirror and enveloped me in a thick cloud of soot when the lights changed.

As automotive subcultures go, intentionally modifying your truck's diesel engine to make extra pollution is one of the more antisocial ones out there. According to the US Environmental Protection Agency, diesel trucks with disabled emissions controls are far more widespread than you might think and emit more pollution than the diesel engines that got Volkswagen such hefty fines.

In 2016, Volkswagen agreed to a pair of court settlements totaling nearly $16 billion after it was caught selling diesel vehicles fitted emissions defeat devices. In total, the VW scandal affected more than half a million cars and SUVs sold in the US, which produced up to 40 times the legal limit of nitrogen oxides (NO _x ) when in daily operation.

Enlarge / A 1980s Mercedes-Benz diesel belches exhaust fumes in London. People expected diesel engines of this vintage to be dirty, but we had a right to expect that diesel engines sold over the past decade complied with emissions laws. Turns out, they don't. (credit: Richard Oliver/Getty Images)

In 2020 it seems more usual to read about the US Environmental Protection Agency rolling back pollution laws or arguing that big business should be allowed to do what it wants . But apparently the agency does occasionally work as intended. Earlier this week, together with the US Department of Justice and the California Air Resources Board, it held Daimler AG—parent company to Mercedes-Benz—accountable for selling diesel vehicles fitted with emissions defeat devices.

EPA and CARB found that all was not right with the Daimler's diesel engines in the wake of the 2015 Volkswagen emissions scandal . EPA told Daimler it was going to conduct some additional tests of the company's four- and six-cylinder diesel engines "using driving cycles and conditions that may reasonably be expected to be encountered in normal operation and use, for the purposes of investigating a potential defeat device."

In doing so, it discovered several auxiliary emission control devices that were not described in the homologation paperwork submitted by Daimler. In total, about 160,000 Sprinter vans and about 90,000 Mercedes-Benz vehicles are affected, between model years 2009 and 2016.

Enlarge / A natural gas flare from an offshore oil drilling rig in Cook Inlet, Alaska. (credit: Paul Souders | Getty Images )

The Environmental Protection Agency this week finalized a rule that kills off Obama-era limitations on how much methane, a potent greenhouse gas, oil and natural gas producers are allowed to emit into the atmosphere—even though industry leaders didn't want the changes.

The changes to the rules, known as the New Source Performance Standards (NSPS), remove some segments of the industry from being covered under the existing standards at all, and these changes also lift the methane caps on other segments, the EPA announced on Thursday.

The oil and gas industry basically splits into three big buckets of activity: upstream, meaning the actual drilling for oil or gas; midstream, which is the world of storage and pipelines; and downstream, that last mile where products are refined and sold. The current changes apply to the downstream and midstream segments, as the EPA broke down in a graphic ( PDF ).