At proving grounds and training ranges across the planet, hundreds of thousands of US Army bullets litter the landscape. Difficult to remove, and a groundwater and soil hazard as they corrode, this discarded metal is an environmental concern. In November, the Department of Defense (DoD) posted a call for proposals titled “Biodegradable Composites with Embedded Seeds for Training Ammunition” through the Small Business Innovation Research (SBIR) federal program. The call emphasizes the issue:

The projectiles, and in some circumstances the cartridge cases and sabot petals, are either left on the ground surface or several feet underground at the proving ground or tactical range. Components of current training rounds require hundreds of years or more to biodegrade. Further, civilians (e.g., farmers or construction crews) encountering these rounds and components do not know if they are training or tactical rounds.

DoD specifically cites “low velocity 40mm grenades; 60mm, 81mm, and 120mm mortars; shoulder launched munitions; 120mm tank rounds; and 155mm artillery rounds” as needing biodegradable substitutes, adding that the US Army Corps of Engineers’ Cold Regions Research and Engineering Laboratory has “demonstrated bioengineered seeds that can be embedded into the biodegradable composites and that will not germinate until they have been in the ground for several months.”

Bullets that contain seeds might seem like a silly design challenge, but ecological destruction by the military is serious. A 2014 article by Alexander Nazaryan for Newsweek noted that the “US Department of Defense is one of the world’s worst polluters,” with “4,127 installations spread across 19 million acres of American soil,” including over 140 Superfund sites. And this problem of tactical waste extends beyond the military. A 2004 report from Virginia Tech reported that there were “20 million metric tons of lead bullets fired in the United States in the 20th century,” with results including large amounts of lead discovered in trees near shooting ranges. Currently, Providence, Rhode Island, is planning to spend a million dollars to extract lead bullets and other fragments from a police shooting range located a few hundred feet from a reservoir.

This DoD call, albeit speculative, offers a sliver of hope for federal environmentalism in areas of the government unlikely to be limited under the Trump administration, which is promoting Scott Pruitt, who has actively challenged regulation of pollution and carbon emissions, to lead the EPA, while the president has signed an executive action to advance the Dakota Access Pipeline. DoD has, in the past, released reports like the one in 2015 that considered the security implications of climate change, acknowledging its reality, and not as a Chinese hoax.

Of course, there is a lot to consider here, such as whether invasive species would be used (if, perhaps, the bullets focus on plants adept at remediation rather than native flora), and if mass seeding would have a negative impact on the area’s biodiversity. Nevertheless, it’s improbable that the United States will be cutting back on its military training anytime soon, and considering the longterm consequences of this ammunition is necessary for a country that values the future of its lands.

Read more about the “Biodegradable Composites with Embedded Seeds for Training Ammunition” call for proposals at SBIR. Proposals are open through February 8.