In the absence of such new statutory authority, the Fed has indicated it might need to alter the way it implements monetary policy, in the event that required reserve balances fell further and the volatility of the funds rate increased. To date, because the volatility of the funds rate has not increased, moving in this direction has not been necessary.
However, if the volatility of the funds rate did increase, one possibility would be to introduce a regime of floors and ceilings that would limit the fluctuation in the federal funds rate to an acceptable range.