In the Southern Hemisphere, where the June solstice is known as the shortest day of the year, it marks the first day of astronomical winter, but the middle of winter in meteorological terms.
Backfill refers to products or materials used to fill excavations. The most common form is composed of a mixture of gypsum and calcium bentonite. Apart from filling holes, one of the primary purposes is to mantle sacrificial anodes under the ground.
7 - 1. SECTION 7. EXCAVATION AND BACKFILL FOR PIPELINES. 7.1 GENERAL. The work covered by this specification consists of furnishing all labor, tools, materials, equipment, and performance of all operations in connection with the excavation, trenching, and. backfilling for underground pipelines and appurtenances.