Well, if you go online and search out a definition for "impact," this is what you get:
1. the striking of one thing against another; forceful contact; collision: The impact of the colliding cars broke the windshield.
2. an impinging: the impact of light on the eye.
3. influence; effect: the impact of Einstein on modern physics.
4. an impacting; forcible impinging: the tremendous impact of the shot
5. the force exerted by a new idea, concept, technology, or ideology: the impact of the industrial revolution.verb (used with object)
6. to drive or press closely or firmly into something; pack in.
7. to fill up; congest; throng: A vast crowd impacted St. Peter's Square.
8. to collide with; strike forcefully: a rocket designed to impact the planet Mars.
9. to have an impact or effect on; influence; alter: The decision may impact your whole career. The auto industry will beimpacted by the new labor agreements.verb (used without object)
10. to have impact or make contact forcefully: The ball impacted against the bat with a loud noise.
11. to have an impact or effect: Increased demand will impact on sales."
"NO Impact" clearly means the opposite.
Which lands us upon "No Impact Man."
"No Impact Man" was a movie, documentary, experiment on NOT making an impact on the environment. Like I said: it's a book, it's a movie, it's a blog. It could even be called a way of life.
There's even a follow-up with "How To Be Alive: A Guide to the Kind of Happiness that Helps the World"
It even made its way to the world of podcast (and a very good one at that): "The Good Life Podcast, Colin Beavan: No Impact Man on How to Be Alive"
You can buy the movie from the website, or rent or buy it from Amazon.
Dictionary definition from http://dictionary.reference.com/browse/impact; Images from http://noimpactproject.org/experiment/ and http://envs1010f11.bgsu.wikispaces.net/Alex+Hoffman; video from https://www.youtube.com/watch?v=Z9Ctt7FGFBo