Every year, we hear about the same struggles when it comes to passing environmental laws.

On the one hand, there are clean-air, clean-water and open-space advocates pushing their case. They want de-nitrifying septics, stormwater controls, renewable energy.

On the other, there are the real-estate agents, the local government officials, farmers and organized labor. They talk about lost jobs, unfunded mandates, higher real-estate prices, unfair tax burdens, burdensome regulations.

Often it’s easy to see why each side takes the position it does. Denitrifying septics are great for helping to clean the wastewater in places that don’t have sewage treatment plants. But they’re going to add thousands of dollars to the price of a home, and that home is harder to sell, so  homebuilders don’t like them. Stormwater is a problem and needs to be cleaned up, but if you’re a county councilman, and your constituents are complaining they can’t afford the fees needed to support the work, you’ll do what you can to make it affordable for them.

But there are some bills where it’s really hard to determine the constituency. Who, exactly, wants arsenic in our chicken? It’s unclear, but it took years to get arsenic out of the chicken feed that poultry companies use. And even then, the bill exempted one drug that contains arsenic, so it’s unclear did anything to protect consumers.

Environmental groups worked for years to get the arsenic ban passed, with a group called Food and Water Watch among the most vocal. The General Assembly asked for a study on how bad it was to have arsenic in poultry feed, and the University of Maryland Center for Agro-Ecology produced one. The answer? It was not good, and its presence in feed puts a burden on consumers who have to figure out which brands use the additive and which do not. (Perdue, the largest producer in Maryland, has not used arsenic since 2007.)

The study concluded that arsenic was not only bad for meat-eaters, it was also bad for waterways,  particularly on the Shore, where millions of birds are grown. Once the study was completed, the ban passed.

Another bill that’s taken a long time to get traction is a pesticide database bill. This bill would not ban the use of pesticides. It simply would create a database of what farmers are spraying and when. With many chemicals, like atrazine, suspected to be responsible for sex organ mutations in amphibians and fish; catastrophic deaths in bee and butterfly populations around the state; and the real possibility that pesticides can damage well-water, it seems like a sensible idea. Why not know what’s being sprayed? Farmers are so busy spraying that they don’t have time to enter this information into a computer, the Farm Bureau has contended. Really? How long would such data-entry take? Isn’t it worth it so the public knows what’s being released into the environment?. The pesticide bill has lost the past several years, despite wide public support, and the Maryland Pesticide Network is making another go of it this year.

Then there is the Black Liquor Bill.

In 2004, a group of environmentalists pushed for a renewable energy standard to ensure that a portion of our state’s energy came from renewable sources. Paper company lobbyists inserted a provision to burn black liquor, a byproduct of making paper. As the years went on, black liquor accounted for a growing shared of the required renewables, though it wasn’t environmentally better than wind or solar and it wasn’t cheaper. In 2013, legislators introduced a bill to take black liquor out of the renewables portfolio. Not stop paper companies from burning it - they still could - but just not consider it renewable energy worthy of credits. The one paper company in Maryland would be exempted in perpetuity, and it initially supported the bill.

Who didn’t support it? The steelworkers and other labor unions, and the paper industry. It would not affect Maryland jobs or the lone Maryland paper plant, and still advocates could not get it passed. Paper companies were afraid, perhaps, that Maryland would set a standard that other states would copy. And labor, perhaps, wanted to stand with its brethren in other states. But really, it’s hard to say why it failed, just as it is hard to explain legislators’ opposition to arsenic-free chicken or pesticide records.

“It’s the mother of all incomprehensible bills,” said Mike Tidwell, executive director of the Chesapeake Climate Action Network. “The only constituency for black liquor are interests out of state.”

But Tidwell is fighting for it again this year, and he has hopes he will win.

“It’s a specific thing, and it sounds a little wonky, but it has a huge impact on clean energy,” Tidwell said. “We’ve assumed, and I think we’re correct, that we’re going to take care of this business this year.”