In my hypothetical situation, we're producing PLA for the sole and expressed purpose of sequestering CO2. My reasoning was that PLA degrades less readily than

In my hypothetical situation, we're producing PLA for the sole and expressed purpose of sequestering CO2. My reasoning was that PLA degrades less readily than plant matter, so less likely to release CH4. But I hadn't thought of the fact that if you bury plant matter deep enough, CH4 emissions likely aren't as high a concern.