BP scientists offer only two possible explanations:
1. There is a significant underground leak from the well.
2. The oil reservoir pressure has dropped due to depletion from 80 days of spill.
I believe the pressure deficiency clearly indicates there is a big leak underground. Almost every one fail to notice to another data which is more important, and more disturbing: Why it is so slow for the pressure to approach its final equilibrium level. It's been more than two days and the pressure still hasn't fully stabilized yet! If the well has no leak, since the volume of oil in the well is small, and the liquid oil is hardly compressible, the well pressure should promptly raise to equilibrium level and stabilize within a few minutes after the sealing cap is shut off.
How fast the pressure builds up to equilibrium level depends on three things:
1. How fast the reservoir oil can gush in under the pressure difference. The faster the oil gushes, the faster the pressure builds up.
2. How big a volume the oil in the well is confined to. The more room there is, the longer it takes to squeeze in extra oil to build up the pressure.
3. How compressible is the oil. The less compressible the oil is, the harder it is squeeze extra oil into the volume and therefore the faster the pressure reaches equilibrium.
Based on the estimate that reservoir oil was gushing into the well at a flow rate of 50,000 barrels per day, the total confined volume of oil the well is no more than 6500 barrels. And the compressibility of that amount of oil (liquid is not very compressible!) gives no more than 50 barrels extra space under full pressure. It takes roughly 3 * 50/50,000 of one day, or roughly 5 minutes, for the pressure in the well to build up to equilibrium level.
But now it's taking much longer than 5 minutes, and the pressure is far from stabilized yet. At the start the pressure was at 5000 feet deep water pressure level, or 2250 PSI. After the first 24 hours it reached 6700 PSI. After 48 hours it was 6745 PSI. After 72 hours it was 6775 PSI. Now after 4 days it's nearly 6800 PSI. The fact it is raising so slowing, and the pressure fails to stabilize, is a very troubling sign.
The data tells us that the oil is confined in a volume way much bigger than just the well itself. As the oil gushes into the well, it simutaneously leaks out of the well, through a pierced opening, into a way much bigger pocket of storage within the seabed rocks. This is why the pressure builds up extremely slowly. Lots of oil is being squeezed out through the leak point into the giant pocket in the seabed, to build up the pressure there slowly over time.
There is no question that the well casing is compromised and there is a huge leak some where in the well casing.
So why can't BP spot any seepage of oil out of the sea floor, if the oil is leaking out of the well into the seabed? That's because the well itself is 3 miles deep under the sea floor. If the oil seeps through the seabed and leak out from sea floor, it does not necessarily come out of the vicinity of the well site. It can come out at ANY spot within a roughly 3 miles radius from the well site. That is a pretty wide area to look for leaks. It is also pitch dark at the sea floor, the ROV video camera must use artificial lighting and can not see more than a living room's area of sea floor at at time.
if there is one single leak out of the sea floor within a 3 mile radius, it will take forever for BP to discover it using those under-sea ROVs. If BP find one leak, that means there must be hundreds of un-discovered leaks out of the sea floor!