Before starting 1st circulation of driller’s method, you have this following information
Original Shut in Drill Pipe Pressure = 500 psi
Shut in casing pressure = 800 psi
After complete the 1st circulation, you shut down pumps and you see the drill pipe pressure and the casing pressure as this figure below
What do you think about this well?
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Answer: Everything is perfect. After the kick is circulated out of hole, once you shut down circulation, you should see both gauges reading the same number which is equal to the original shut in drill pipe pressure.
You can read more explanation here > https://www.drillingformulas.com/drillers-method-quiz-no-1
Reference books: 
Well Control Books
