Based solely on this information, you would expect to find a few SQL statements dominating block read consumption. Looking at the SQL statements, sorted by block reads, you see that two statements clearly are consuming the majority of block read requests. The connection between the Oracle and the application subsystems has been made.

Notice that you have not pointed a finger at anyone; therefore, it's unlikely that you have offended members of any group and caused them to take an immediate defensive posture. There is a very high likelihood that performance-improving changes can be made to both the SQL and Oracle. So right away, two teams can get involved in solving the problem!

From an operating system perspective, because Oracle processes are waiting for blocks outside Oracle's buffer cache and on average take 22 ms8 to be received from the IO subsystem, you can clearly expect an IO bottleneck. You have not implied that there is a problem with the IO subsystem or that the SQL is poorly written, but the fact remains that it takes 22 ms to complete a multiple-block IO call.