【中文版】

衰竭期煤矿是指开采时间较长、资源枯竭的煤矿。这类煤矿具有以下特点：

首先，资源储量逐渐减少，甚至已经没有可采储量。煤矿的开采时间较长，经过多年的开采，资源逐渐枯竭，可采储量越来越少，开采难度越来越大，开采成本越来越高，经济效益逐渐下降。

其次，安全风险越来越大。随着资源储量的减少，开采深度的增加，以及开采难度的加大，煤矿面临的安全风险也越来越大，矿难事故发生的概率逐渐增加。

此外，环境污染问题也日益严重。煤矿在开采过程中会产生大量的废气、废水、废渣等污染物，对周边环境造成严重的污染。随着资源枯竭，废弃的矿坑和尾矿库也成为了环境污染的重要来源。

最后，社会问题也逐渐凸显。煤矿的开采需要大量的人力资源，但是随着资源的枯竭，很多矿工面临着失业的问题。同时，由于环境污染等问题，周边居民的生活质量也受到了很大的影响。

综上所述，衰竭期煤矿的特点是资源储量逐渐减少直至枯竭、安全风险越来越大、环境污染问题日益严重以及社会问题逐渐凸显。对于这类煤矿，应该采取相应的措施，如关闭、转型等，以保障安全和环境。

【英文版】

A depleted coal mine refers to a mine that has been mining for a long time and its resources are exhausted. This type of coal mine has the following characteristics:

Firstly, the resource reserves are gradually decreasing, or even no more recoverable reserves. The mining time of the coal mine is long, and after years of mining, the resources are gradually depleted, the recoverable reserves are getting smaller and smaller, the mining difficulty is increasing, the mining cost is getting higher and higher, and the economic benefits are gradually decreasing.

Secondly, the safety risks are getting higher and higher. With the decrease of resource reserves, the increase of mining depth, as well as the increase of mining difficulty, the coal mine faces more and more safety risks, and the probability of accidents such as mine disasters is gradually increasing.

In addition, environmental pollution issues are also becoming increasingly serious. During the mining process, coal mines will generate a lot of pollutants such as waste gas, waste water, and waste residue, which will cause serious pollution to the surrounding environment. With the exhaustion of resources, abandoned mines and tailings ponds have also become important sources of environmental pollution.

Finally, social problems are gradually emerging. The mining of coal mines requires a large number of human resources, but with the exhaustion of resources, many miners are facing unemployment problems. At the same time, due to environmental pollution and other issues, the quality of life of周边居民 is also greatly affected.

In summary, the characteristics of depleted coal mines are that resource reserves are gradually decreasing until exhausted, safety risks are getting higher and higher, environmental pollution issues are becoming increasingly serious, and social problems are gradually emerging. For these coal mines, corresponding measures should be taken, such as closure, transformation, etc., to ensure safety and the environment.