How can I ensure that I have clean topsoil for my gardening project?

To ensure clean topsoil for your gardening project, you can start by purchasing topsoil from a reputable source that is free from contaminants. You can also test the soil for any pollutants or chemicals before using it in your garden. Additionally, consider using organic compost or creating your own compost to enrich the soil naturally. Regularly monitoring and maintaining the soil quality will help ensure a healthy environment for your plants to grow.