PEL-PLUG TR30 (TR60 & TR90) – Time-Release Coated Bentonite Pellets â High swelling bentonite with a time-release, biodegradable, non-stick coating. The coating allows the pellets to be poured through standing water without sticking together for up to 30 minutes allowing for deeper settings. Available in 1/4 , 3/8 and 1/2 sizes. Can be tremmied into place or placed through a hollow stem auger. TR60 allows up to 60 minutes and the TR90 up to 90 minutes.