A champagne producer proceeded with the dismantling of a refrigeration installation shut down since 1990 and containing 280 kg of ammonia (45 kW rating). Two technicians from two subcontractors first recovered 250 kg of liquid NH3 in 8 bottles specially intended for this operation. The installation was then degassed by immersing all pipes connected to the unit’s various tapping points in a bucket filled with water. The saturated ammonia solution was then poured, undoubtedly in several sequences, into the manhole of the site’s storm drains. Informed by a neighbour of the presence of ammonia odors in the city’s sewer system, local firefighters solicited the Water Department to notify all personnel potentially working in the area.