In a confusing and potentially far-reaching decision last week, the U.S. Environmental Protection Agency reaffirmed the state’s authority to establish water quality standards for “waters in Indian lands.” But the agency then told the state that some of its water quality standards are not protective enough of tribal members.

State regulators were told they must rewrite some of the state’s water quality standards, dating from 2004 to 2013, for “waters in Indian lands” to ensure they are clean enough to allow tribal members to continue sustenance fishing, as guaranteed by the Maine Indian Land Claims Settlement Act.

The lands in question were purposely set aside by the Settlement Act so the tribes could continue sustenance living, including fishing, the EPA said. “To adequately protect that sustenance fishing use, the State must revisit two aspects of its analysis supporting the human health criteria that determine how clean the waters must be to allow the Tribes to safely consume fish for their sustenance,” the EPA wrote in the analysis supporting its decision. Fish consumption among tribal members may be more than 10 times that of the average Mainer, the agency said.

The state’s tribes hailed the Feb. 2 EPA action as good news, but it leaves unanswered questions that must quickly be addressed in order for the state’s water quality standards to be effective — for the tribes and the rest of the state.

The first issue is that the EPA did not define “waters in Indian lands,” so state regulators are left to guess what this means. Does it includes rivers, such as the Penobscot and St. Croix, that flow along or around tribal land? Or does it refer just to streams that flow through Indian lands? The decision applies to the Penobscot Nation, Passamaquoddy Tribe, Houlton Band of Maliseet Indians and the Aroostook Band of Micmacs.

Second, the EPA decision seems to set up two sets of standards, one for waters in Indian lands and another for the rest of the state. Is this feasible, or does it mean that the Indian land standard becomes the de facto standard for those upstream, or even downstream, from Indian lands? Is this necessary?

The state has 90 days to comply with the EPA’s decision, which appears to run counter to a 2007 federal court decision giving the state full authority to regulate water quality in rivers that run through tribal territory. As a result, the state is likely to sue the EPA — again — to seek clarity on what it can and can’t do with regard to waters in Indian lands.

The EPA’s action does nothing to bring the needed clarity to an issue that has been unresolved for more than 15 years.

In 1999, the state applied to the EPA for authority to issue federal wastewater discharge permits under the Clean Water Act. Indian tribes in Maine objected, saying they thought the federal government should retain oversight in tribal territories because the state was too lax.

In 2001, the EPA gave the state Department of Environmental Protection permitting authority in most of Maine, but said it needed to study further what to do in Indian territory.

Two years later, the EPA decided that the federal government would retain jurisdiction over the treatment plants while the state would control the issuance of permits for other discharge sites. Both the tribes and state sued the EPA.

A federal appeals court in 2007 rejected the tribes’ appeal of EPA’s delegation of authority to the state and went further to say that the state should also regulate treatment plants.

Eight years later, the EPA is now saying Maine has jurisdiction to issue discharge permits, but its human health standards aren’t strong enough for “waters in Indian lands.”

The EPA and Maine DEP have a responsibility to protect the health of everyone in Maine, including tribal members. This unexpected decision that could undo a decade of permits is unlikely to rebuild the trust needed for the state and tribes to work together on water quality and other contentious issues.

The BDN Editorial Board

The Bangor Daily News editorial board members are Publisher Richard J. Warren, Editorial Page Editor Susan Young, Assistant Editorial Page Editor Matt Junker and BDN President Todd Benoit. Young has worked...