If you cannot or do not want to utilize the chlorine in your pool, then it should be taken to a hazardous waste facility. Usually, such a facility is located at the same place as your garbage collector / recycler "dump". It's the same place that would take your partially or fully empty paint cans, motor fluids, etc.

Such facilities know how to handle various wastes. In the case of chlorine, they will likely neutralize it by dissolving it and adding a reducing agent turning the chlorine into salt. Just be sure to tell them exactly what it is or have it in its original container with its label.

Richard