Peter Klevberg is a Civil Engineer affiliated with Creation Ministries International, and hence a hardcore young earth creationist. In fact, Klevberg appears to be affiliated also with Answers in Genesis, and has written or contributed to several articles for their house journal Answers Research Journal. To volume 1, for instance, Klevberg coauthored (with Michael Oard) “Green River Formation Very Likely Did Not Form in a Postdiluvial Lake”, which looks at the data that fits their concluion and disregards the rest, which they are apparently allowed to do because of Jesus. The article, of course, appears to assume the most recent developments in Flood Geology, developments that have made Flood Geology just as respectable as it was before.
Apparently flood geology is something Klevberg considers an area of expertise, and his work is sometimes cited by other creationists in lieu of anything better that doesn’t completely contradict whatever they want to believe in.
Diagnosis: Stock denialist fundamentalist. His personal influence is probably limited, though he does add momentum to the denialist movement by sheer deadweight.