ABSTRACT: Many inactive rock quarries are deep, abandoned, water-filled pits with near-vertical walls. Reclaiming a quarry site or investigating a quarry bottom may require draining the quarry. However, rapid drawdown of the quarry water level may reduce the stability of the quarry walls to their lowest level ever experienced. Therefore, there is a risk of quarry wall failure. If a wall failure would have serious consequences, then a detailed stability evaluation must be done to assess the conditions before drawdown and the expected reduction in stability during drawdown. A case history of a successful drawdown at an abandoned quarry is presented. In this case, the quarry wall was 230 feet high with an overhanging face. Failure of the quarry wall was unacceptable, because a criminal investigation required access to the quarry bottom below the overhanging wall. The geotechnical approach used to maintain wall stability while maximizing the drawdown rate is described. Factors that controlled the drawdown rate are discussed.

This content is only available via PDF.
You can access this article if you purchase or spend a download.