The first admission can be found in the first part of his testimony.
"I back tracked and then as I was coming up towards the ditch I walked a little farther down, so I could come up around, as I came up on the ditch I was looking down on, it sort of sloped down and I noticed something shiny. So I stopped and it was a little, it wasn’t very level, so I braced myself, and I leaned down and I could just see a top part of, well, I just saw one part, I wasn’t sure if it was a top part or whatever, so I reached down and I grabbed it, and then when I stood up and I looked closer at it, I realized what I had picked up."
Even though at the time of his testimony the officer knows what he had found was a pipe bomb, as he tells his story he should be telling it as he lived it. What he wants us to believe is that he saw a shiny object in the ditch and did not know what it was until he got closer to it and picked it up. The problem is he tells us "I could just see a top part of....." How did he know it was the top part he was looking at? It is because he knew what it was before he walked over to it. He realizes his mistake and tries to correct himself by saying "well, I just saw one part, I wasn’t sure if it was a top part or whatever." However, the damage was done. He told us he saw the top part because he knew what he was looking at.