Suchergebnisse

In Australia, all states and territories in Australia have maintained their own and separate set of laws for regulating health and safety. The difference has been more pronounced in the mining sector. The main reason for maintaining these separate regimes in mining has been based on an old-age argument that the hazards, culture and circumstances of the mining industry are somewhat different to those existent in other industries. As a result there are at least three different structures of the health and safety law in Australia. In recent years, however, there has been push by industry and government to drive some consistency and harmonization in regulating health and safety. To address this disparity the Federal Government has, in consultation with the states and territories, developed and issued the Model Work Health and Safety Act (WHSA) and the Model Work Health and Safety Regulations (WHSR) which is expected to become a uniform set of health and safety laws for the country. For the mining sector, a draft set of Regulations and Codes of Practice aimed at harmonizing health and safety has been issued. It is expected this will provide the country's first ever set of standards and benchmarks for the mining sector. This paper compares and contrasts the existing and the proposed set of laws in the three states of Victoria, Queensland and Western Australia. It concludes with a discussion on what the proposed laws mean for managing risks associated with ventilation in underground mining

Changzhou City, underlain by a multi-layered aquifer system in Quaternary sediments in the Great Yangtze River Delta region, experienced a maximum land subsidence rate of 147 mm/year in the early 1980s due to excessive groundwater extraction. A large-scale monitoring station of 11 borehole extensometers was established in the city in 1983 to investigate land subsidence. Nine strata were predetermined in the Quaternary depth interval and monitored by borehole extensometers. Presented in this paper are the long-term observations of land subsidence, strata compression and groundwater level in four aquifers from 1984 to 2002, and discussion on strata compression based on the measured data with reference to the stratigraphy, soil properties, groundwater withdrawn and literature of similar situations. The compression of strata varies significantly and is strongly influenced by groundwater drawdown in the second confined aquifer, or CA2. The groundwater level in CA2 declined from - 55 m in 1981 to - 76 m in 1994 and the land subsidence rate remained high. After the city government enforced restrictions on groundwater extraction in 1995, the extraction rate sharply reduced, the groundwater level in CA2 steadily recovered to - 56 m until 2003, and the land subsidence rate declined to 10 mm/year in 2002. From 1984 to 2002, the land subsidence was mainly attributed to the consolidation of the thick aquitard overlying CA2. In the future, to prevent the subsidence rate from rising, it is vital to stop groundwater drawdown in aquifers. © 2008 Elsevier B.V. All rights reserved.

Changzhou City, underlain by a multi-layered aquifer system in Quaternary sediments in the Great Yangtze River Delta region, experienced a maximum land subsidence rate of 147 mm/year in the early 1980s due to excessive groundwater extraction. A large-scale monitoring station of 11 borehole extensometerswas established in the city in 1983 to investigate land subsidence. Nine stratawere predetermined in the Quaternary depth interval andmonitored by borehole extensometers. Presented in this paper are the long-term observations of land subsidence, strata compression and groundwater level in four aquifers from 1984 to 2002, and discussion on strata compression based on the measured data with reference to the stratigraphy, soil properties, groundwater withdrawn and literature of similar situations. The compression of strata varies significantly and is strongly influenced by groundwater drawdown in the second confined aquifer, or CA2. The groundwater level in CA2 declined from −55 m in 1981 to −76 m in 1994 and the land subsidence rate remained high. After the city government enforced restrictions on groundwater extraction in 1995, the extraction rate sharply reduced, the groundwater level in CA2 steadily recovered to −56 m until 2003, and the land subsidence rate declined to 10 mm/year in 2002. From 1984 to 2002, the land subsidence was mainly attributed to the consolidation of the thick aquitard overlying CA2. In the future, to prevent the subsidence rate from rising, it is vital to stop groundwater drawdown in aquifers.