2024 Iowa Code 208.21 – Political subdivision engaged in mining

2023 Iowa Code 208.21 – Political subdivision engaged in mining

2022 Iowa Code 208.21 – Political subdivision engaged in mining

2020 Iowa Code 208.21 – Political subdivision engaged in mining

2018 Iowa Code 208.21 – Political subdivision engaged in mining

2016 Iowa Code 208.21 – Political subdivision engaged in mining

2014 Iowa Code 208.21 – Political subdivision engaged in mining.

2009 Iowa Code 208.21 – Political subdivision engaged in mining