The U.S. Army has posted a solicitation for biodegradable ammunition to be used during training exercises.

In the solicitation, the Army notes the branch manufactures and consumes hundreds of thousands of rounds for training events that may require 100 years or more to biodegrade.

By replacing existing ammunition with biodegradable alternatives, the Army says it can reduce potential environmental hazards. The long-term effects of current training rounds can include pollution and corrosion of soil and nearby water.

To remedy the situation, the Army is seeking biodegradable alternatives for low-velocity 40mm grenades, various mortar shells, shoulder-launched munitions, 120mm tank rounds and 155mm artillery rounds.

"The biodegradable materials identified can be utilized by private industry to manufacture biodegradable water bottles, plastic containers, or any other composite or plastic product(s) on the market today," the Army said in the solicitation.

The U.S. Army Corps of Engineers has bioengineered seeds to withhold germination for several months until the new materials naturally degrade. The seeds can also consume contaminants as they grow.

Once a contract is awarded, the work will be divided into three phases. During the first phase, the contractor will develop a process to produce biodegradable composites with remediation seeds for 40mm and 120mm training rounds. In the second phase, the contractor will manufacture prototypes and perform ballistic tests. For the third and final phase, the contractor will collaborate with PEO Ammunition and other contractors to establish a transition path.

Contractors have until Feb. 8 to submit proposals.