What is the preferred material for grouting?

Neat cement is commonly preferred for grouting due to its strength, durability, and ability to provide an impermeable seal. It consists of a simple mixture of Portland cement and water, which creates a strong bond when it hydrates and cures. This bonding is essential in applications like well sealing and stabilizing surrounding soils, preventing contaminants from entering groundwater resources.

The ability of neat cement to expand slightly as it cures also helps in filling voids effectively, ensuring better contact with the well casing and surrounding materials. Additionally, it has a proven track record in the industry, making it a reliable choice for various grouting applications.

Other materials mentioned, such as gravel mixtures, sandy clay, and plastic resins, have specific applications or drawbacks that may make them less suitable depending on the scenario. Gravel mixtures may not provide a thorough seal and could allow water to flow, while sandy clay may not achieve the necessary bonding or impermeability. Plastic resins, although useful in some contexts, may not offer the same level of structural support or compatibility with traditional cementing procedures.