COMSTOCK TOWNSHIP -One year after the largest oil spill in the Midwest's history, representatives from three state environmental groups called on U.S. Reps Fred Upton, R-St. Joseph, and Tim Walberg, R-Tipton, to support the regulatory powers of the U.S. Environmental Protection Agency.

"Last year's tragedy continues," said Cyndi Roper, Michigan director of Clean Water Action, an advocacy group.

That tragedy, Roper said, was that the two lawmakers supported the Clean Water Cooperative Federalism Act of 2011, which would take away the EPA's oversight of water standards.

Currently, if a new building or project violates federal water regulations the EPA can step in and regulate, said Rita Chapman, clean water program director for the Sierra Club's Michigan chapter.

The EPA has opposed the bill because it would take away the agency's ability to action if a state's water policy would adversely effect public health.

The bill would upset "the CWA's balanced approach to improve water quality across the Nation, risking the public health and economic benefits of cleaner waters," according to an EPA statement.

The bill would put the regulatory power in the hands of the states, which could be a problem for Michigan, advocates said.

The House passed the bill 239 to 184 earlier this month. It still has to be voted on by the Senate.

"Congressmen Upton and Walberg should know better than anyone in Congress that the EPA is critical to protecting the water we drink and the air that we breathe," said Roper.

"The oil spill last year left people ill, destroyed property values and damaged our natural resources in ways that will be felt for years to come," she said. "It is a devastating reminder that the EPA plays a critical role in protecting our land, air and water."

The press conference was held in front of a parking lot for Enbridge contract workers near Morrow Lake. The EPA recently announced that there is 200 acres of submerged oil found during a spring assessment of the areas affected by the oil spill.

The submerged oil is a trait of the diluted bitumen oil that was being transported through the pipeline at the time of the spill. The oil is derived from oil sands in Alberta, Canada, and diluted with natural gas condensates to make it pass through a pipeline.

Enbridge estimates that about 819,000 gallons of heavy crude oil was released from Pipeline 6B. Around 716,000 gallons have been recovered.

At Ceresco Dam, contract crews are stirring up the the bottom of the river to release the trapped oil. It is then collected on the surface of the water.

Beth Wallace, with the National Wildlife Federation's Great Lake Regional Center, said that the oil needs to be studied before new diluted bitumen, or tar sands, pipelines are constructed, such as Keystone XL, a proposed 2,000 mile pipeline from Alberta, Canada to Texas.

Environmentalists attacked Upton earlier in the year for weakening the Clean Air Act by preventing the EPA from regulating carbon dioxide emissions.

In a viewpoint in the Kalamazoo Gazette, Upton said "the Environmental Protection Agency (EPA) has changed course, now seeking to regulate greenhouse gas emissions by bureaucratic fiat."

Chapman said the EPA is being targeted by lawmakers because deregulation helps businesses make more profits.

"Federal oversight is key to keeping out air and water clean," she said. "As incomplete as the cleanup still is today, it would have been far worse without the EPA."

7:30 p.m. update: Meghan Kolassa, a spokeswoman for Upton, there is no correlation between the bill, pipeline safety and the clean up of the Kalamazoo River.

Upton has led the charge for stronger pipeline regulation in the House Committee on Energy and Commerce, which he chairs, she said.