Many households in areas where mining or drilling takes place are outside of the service of public water supplies. These property owners rely on water wells for the production of their water. When underground mining occurs beneath a property, some subsidence and settlement should be expected. If the mine is below the aquifer tapped by the well, subsidence of the mine could damage the aquifer, causing its water to drain into deeper rock units. This can cause a temporary or permanent loss of the water supply. It can also ruin the quality of the water. The value of a rural property without a water supply is a lot lower than the same property with a water supply.