Water industry, clean water pipelines.

Before man entry into the pipe, it is a requirement to chloros wash footwear & tools to be used in the pipe (aside from confined space procedures). Upon completion of the job I am trying to determine the best course of action in regard to the disposal of the chlorinated water (around 15-20 litres).

Option 1 - Decant, bring back to base and dispose down foul water drain

Option 2 - Use sodium thiosulfate crystals to neutralise and dispose at point of work

Just wondered if anyone on here has a procedure for a similar process that they care to share to enable me to develop a best practice?

Thanks.

Yes, I have this document which states both of the above options are good practice but just wondered what others find the best solution is. Decanting and transporting and further handling has its risks as does carrying additional chemicals for option 2.....................