They worked in coal mining and metallurgy. It closed following privatisation of the coal mining industry. A modest amount of opencast coal mining continues. Other significant economic resources include oil, gas, coal, hard rock mining, and lumber. The borough expanded dramatically in population with the development of coal mining. Wollongong has a long history of coal mining and industry. Mining and refining platinum has environmental impacts. There are reported labor shortages in agriculture, mining, and construction. There are a range of hazards present in surface and underground mining operations. They moved to Mexico where Harold worked in gold mining operations. This decline has a significant influence on the mining and refining of strontium. The Chinese companies found business in telecom, mining, and railroads. Canada shows significant growth in the sectors of services, mining and manufacturing. The rivers face problems such as sand mining and pollution. The Group has interests in mining and engineering.