2024 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2023 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2022 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2021 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2020 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2019 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2015 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2014 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2010 30 CFR 817.15 – Casing and sealing of underground openings: Permanent

2009 30 CFR 817.15 – Casing and sealing of underground openings: Permanent