The Crooks are unable to move their narrowboat until the testing is complete.
“They want the water to stay as undisturbed as possible. As a first step it seems they want everything to stay still,” Bruce Crook told the PA news agency.
“The locks were closed because of repairs required, but by Monday afternoon, it was a wider stoppage. So we can’t move.”
Experts have described the spill as a “cause for concern” due to risk to the ecosystem and people who come into contact with the toxic water.
“Ingestion of water containing a sufficiently high concentration of sodium cyanide can result in classic poisoning symptoms,” said Dr Jonathan Paul, senior lecturer in Geosciences at Royal Holloway, University of London.
Depending on the amount ingested, people could experience nausea, aches, weakness and loss of consciousness.
A local company has taken responsibility for the spill on Wednesday. Anochrome Ltd, which supplies specialist surfacing coatings, said a “chemical incident occurred” on Monday morning and chemicals were released into a canal in Walsall as a result.
Over a hundred dead fish have been spotted in the canal, poisoned by the toxic chemicals.
Reports claim several agencies have gathered to control the incident including the West Midlands Police and Fire services, Walsall and Sandwell councils, the Environment Agency, the Canal and Rivers Trust and Severn Trent Water.