Abstract: An antifreeze gel composition is provided which is particularly useful in preventing ice formation and in dissolving ice already formed in a cable conduit line. The composition includes a water soluble antifreeze agent such as an alkylene glycol, a thickening agent, and water. A two-part chemical duct block kit for use in a cable conduit is also provided which includes the above antifreeze gel composition containing additional alkylene glycol in a first container, and a solid absorbing agent powder for aqueous liquids in a second container. When the powder is added to the antifreeze composition, a solid composition is formed which can block liquids and gels from passing through a conduit.