  In this paper, we describe a future electron-ion collider (EIC), based on the
existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two
intersecting superconducting rings, each 3.8 km in circumference. A new ERL
accelerator, which provide 5-30 GeV electron beam, will ensure 10^33 to 10^34
cm^-2 s^-1 level luminosity.
