Controlling odour is a major challenge affecting expansion of the livestock industry in Western Canada. Manure-storage facilities account for about 30 percent of the
complaints about livestock odours. Covering these facilities can reduce odour and gas emissions by 70 to 95 percent. This report describes the results of:
1. Field tests on a full scale prototype that demonstrated the concept of a negative air pressure (NAP) cover for earthen manure storages 2. A survey of neighbours living around two earthen storages covered with NAP covers 3. Monitoring of the manure quality in a NAP covered earthen storage.

Project Goals
The project goals were to: 1. Demonstrate and evaluate the performance of the negative air pressure cover system under field conditions; 2. Evaluate different ways to anchor the covera