An Indiana regulatory panel passed new rules Wednesday aimed at protecting the quality of the state's waterways.

The Indiana Water Pollution Control Board met Wednesday afternoon in Indianapolis to approve the state's new anti-degradation rules. The new rules are aimed at lowering the levels of pollutants released into waterways by companies.

Kim Ferraro of the Hoosier Environmental Council said that under the previous system, when someone applied for a permit to release wastewater into Indiana waterways, there were blanket limits on the levels of pollutants companies could release. The rule didn't take into account what may have already been in the waterway.

The new rule will require the Indiana Department of Environmental Management to consider whether what's discharged will push levels of the chemical in the waterway to a dangerous or polluting level.

Ferraro said her group was pleased with IDEM's proposed rule.

"It's rare for environmentalists to rally behind something backed by IDEM," Ferraro said.

After months of public comment and board consideration, the approved rule now heads to the attorney general's office for review before being sent to Gov. Mitch Daniels to be signed.

The rules have been in the works since IDEM issued a permit allowing BP to increase its discharges of pollutants after expanding its Whiting oil refinery. Daniels then ordered an independent review, which found Indiana's anti-degradation rules were too vague.

After the uproar over the permit, BP said it would keep the expanded plant's discharges to the same limit of the previous permit. The $3.8 billion Whiting expansion is expected to open next year.

IDEM Commissioner Thomas Easterly said, however, the state has been trying to create an anti-degradation rule for decades.

"For 37 years, Indiana has been required to have these rules but has not had them," Easterly said.

Board chairman Gary Powdrill said the effort to create clearer anti-degradation rules is akin to what he says the state was trying to accomplish with its right-to-work legislation this year — making the state more attractive for businesses that wish to relocate here.

Before this clearer standard, Powdrill said, companies may have looked to states with better permitting procedures.

Easterly received written comments on the rule from 15 different groups prior to Wednesday's meetings. Many criticized the rule as vague, though Easterly said IDEM opted to keep the language less specific to allow regulators to adapt it to a range of permit applicants.

He said the rule was far from perfect, but was a good starting point for the state.

"We're going to find something to change, but we're getting closer," Easterly said.

But Dennis Wene, of aluminum manufacturer Alcoa, said he worried the language was too vague, which he said would make it ineffective. He introduced two amendments to add more specific language and definitions, but both were struck down by the board.

"We want to ensure the rule is applied correctly," Wene said. "There's a lot more work that needs to be done."

Ferraro said ambiguous language in anti-degradation rules can also make them targets for litigation, but she said IDEM's years of consideration were a sign that all the issues had been thoroughly considered.

"This is what can happen when all the stakeholders come together and talk about something," Ferraro said. "This is a really good rule. That doesn't happen often."