Why is mining a big source of pollution ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Mining**: Mining is the process of extracting valuable minerals or other geological materials from the earth. This activity is essential for obtaining resources like metals, coal, and other minerals.

2. **Manmade Activity**: Mining is classified as a manmade activity. Human intervention in natural processes often leads to environmental changes and pollution.

3. **Waste Generation**: During the extraction of metals through mining, a significant amount of waste material, known as slag, is produced. Slag is the byproduct that remains after the desired metal has been extracted.

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