How should cement grout be introduced when plugging a flowing well?

When plugging a flowing well, introducing cement grout from the bottom up is the preferred method. This approach is effective because it allows for better sealing of any voids and ensures that the grout can properly displace any water or output from the well. When the grout is introduced from the bottom, it pushes existing water or flow upward and out of the well, which reduces the likelihood of creating gaps that could allow water to continue flowing.

Introducing grout from the top down, or from the surface only, does not guarantee that it will fill the entire wellbore effectively. These methods may lead to incomplete plugging, as water may push the grout back up before it can adequately settle and fill the voids, especially in a flowing well where pressure can complicate proper placement. Therefore, the method of introducing cement grout from the bottom up is crucial for achieving a secure and effective seal in the well.