The phrase 'immense impact on' is correct and usable in written English.
You can use it to describe the significant effect that something has had on something else. For example: "The introduction of this new technology has had an immense impact on the way we work."
For example, when Ali refused to be drafted into the Army, saying, "I have no quarrel with the Vietcong", this had an immense impact on the black soldiers that made up one third of the US military.
These universities have an immense impact on the regional economy.
Wallinger's installation heroically reflects Freud's immense impact on modern culture.
The social excitements of the 1960s had an immense impact on the hard-working writer in his garret.
Her wisdom, humanity and international experience, had an immense impact on strengthening our emergency teams working in disaster situations.
The computer's immense impact on the social and academic lives of college students is just beginning to become apparent.
The change towards new energy systems with hydrogen gas as an energy carrier will have an immense impact on society.
Landslides exert an immense impact on forest ecosystems and substantially change soil properties; understanding these changes is crucial to facilitating subsequent forest revegetation and management.
After the Arsenal defeat, Clough acted swiftly and brought in two players who would have an immense impact on the team.
It has also had an immense impact on our understanding of medicine, leading directly to such developments as stem cell research, PGD, and many other fields.
The discovery of RNAi has already had an immense impact on biomedical research and will most likely lead to novel medical applications in the future.
