Abstract: In developing countries, it is common to cite industries without carrying out environmental impact assessment. This is the case of the 2 industries audited in this study. It becomes necessary, therefore, to audit food processing industries in Nigeria to determine their impact on geology, soil and ecology. This will enhance a cleaner and healthier environment. In this study, the impact of food processing industries on geology, soil and ecology of their environments were reported. The method adopted is the Investigative Survey Research Approach (ISRA), which involves the collection of baseline and screening data. The effects of pollution on geology, soil and ecology include depletion of natural reserves, endangered terrestrial habitats leading to migration of arboreal animals to safer places and loss of them in the host communities, increased compaction due to increased vehicular and human traffic and reduction in yield of lands within the vicinity of the industries. The reduced soil fertility could be attributed to leachate from chemical wastes from NAS. The need for environmental impact auditing and the importance of impact auditing as a project management tool were highlighted. It was concluded, that the food processing industries do have positive and negative impacts on their environments and recommendations towards alleviating negative impacts on the environment were made.