Eric, I don't know if you have the full screen version of the KATU video but it shows two different levels in the dig where a piece was found. again, this video does not document everything going on. towards the end the reporter is in the hole and it's not 18" deep. not much was found at the 3 foot level. most of the pieces were 2 feet and above.
Yes I have the larger full-screen version.
At the beginning the reporter even states that they're digging "maybe a foot and a half down, two feet at the most." And the footage of the agents in the background substantiate that estimate. The footage also clearly shows the plaid-shirt agent--the guy who finds the shard while filming--in the background too.
Baring in mind that sand is also piled immediately adjacent to the digging all over the place it may appear that the holes are deeper. However, when I looked closely at all of the footage and pictures I estimated that the great majority of what we are looking at is within 18". Nonetheless, we can casually watch the footage and clearly see there is no one waist-deep in some hole.
Also consider this question: If the shards were found 3' deep and these pieces were found on top of the 1974 dredge spoil layer, where did all of this additional sand (at least top 3') come from? Someone shipped it in and piled over 3' feet of sand on top of the dredge spoil layer--which by the way is over 300 feet away--after 1974? Remember, this is after 6 years of constant erosion (1974 dredge to 1980 money find). That suggests that perhaps as much as 5 feet of fresh sand somehow ended up on top of the 1974 dredge spoils. That makes no sense.