Many year ago undersigned was a member of the sub sea drilling committee based in Aberdeen to investigate what about 10000ft (3000 mtr) drilling ,ie drilling and a accident that time there was under construction an super sub sea BOP stack and nothing can happen! We already proposed a DOME ( up site down Bad-tub) which could be lowered and placed around and on top of the Xmas tree or BOP . After the big disaster in the Gulf of Mexico ,ie leaking BOP sinking Semi and 11 people died ,old team members from Lyon asking where is your Bad-tub,the British Oil company got to pay 7,5 Billion USd , our DOME-CATCHER is cheaper The ST DC can be stored nearby drilling fields our DC can be supported to a submersible carrier, unloading II on location. right positioned with assistance of 3 -4 tugs an large winches for the right tethering, During lowering min. 6 flexible lines (10 or 20 inches ) are connected to a surface ship or tanker ,the reel & manifold are located on top of the Dome. Power source via a Umbilical line with standby assistance from a ROV . The Dome can be constructed from twin hull steel plates or concrete ,different volumes are possible ,herewith our middle sized Dome type STK.DC.7045.128M. 

Outer diameter : 70 mtr. 
Dome height : 45 mtr.
Volume :128.000.000 liters (830.150 barrels)
Lowering water depth up to : 3000 mtr.
Lowering speed : 1 m/min (3000 min.= 50 hrs.)
Reels average diameter : 15 meters. storage 3100mtr.
Weight of Dome : 6600 Ton.

Note : ON top we have our Swedish design for a oil skimmer ,ie the surface waste can be loaded into the skimmer by given the ship a large Roll angle, advantage is 20000 T capacity (see V).