The Natural Resources Council of Maine released its fifth annual report card on the Legislature on Tuesday, giving lawmakers high marks for their work on environmental issues during the session that adjourned last week.

The report continues a trend of environmentally responsible action, said Pete Didisheim, NRCM spokesman.

“Over the last two years the Legislature has had relatively good grades,” he said. “It’s a strong improvement over four or five years ago, when we were giving D’s and F’s.”

The lowest grade on the 2003 report card was a B, though several issues were labeled incomplete because they have not been fully resolved.

The Natural Resources Council of Maine is the state’s largest environmental lobbying group. Its staff testified on approximately 45 issues during this legislative session.

Among the Legislature’s A-worthy accomplishments, according to NRCM, were reducing mercury pollution by prohibiting the sale of mercury-containing products when alternatives are available, requiring dentists to treat wastewater that could contain traces of mercury amalgam from fillings, and improving the collection system for thermostats that contain the element.

The council also gave lawmakers an A for their defeat of several bills that the lobbying group characterized as bad for the environment, including proposals to block dam removals, to limit land conservation, and to abolish the State Planning Office.

NRCM applauded lawmakers’ efforts on climate change, river and watershed protection, forest conservation, and reducing toxic pollution. For each of these lower-rated issues, however, NRCM laid out the shortcomings of the legislative action and suggested improvements.

Many of the issues that received the B grades, such as funding household hazardous waste programs and reducing arsenic pollution, were addressed by bills that passed, but with far less impact than their sponsors had intended.

The full report is available online at www.maineenvironment.org