Which of the following is NOT a source of cyanide waste streams?

Cyanide is a toxic compound often associated with specific industrial processes. In this context, cooling tower treatment does not typically involve cyanide, making it the correct choice as a source that is NOT associated with cyanide waste streams.

In contrast, electroplating involves the use of cyanide baths to adhere metal plating onto surfaces, making it a significant source of cyanide waste. Tanning also uses chemicals that can include cyanide in the process of treating animal hides. Similarly, wood preservation may involve the use of cyanide compounds to protect wood against decay or pests. Therefore, cooling tower treatment stands apart as it primarily deals with the management of water used for cooling machinery or processes, and does not contribute to cyanide contamination.