A formation treatment method for a borehole, the method comprising: isolating a borehole annulus of the borehole around an assembly into a plurality of isolated zones, the assembly in each isolated zone having a port and a screen communicating a through-bore of the assembly with the borehole annulus; positioning a workstring in the through-bore of the assembly; treating the borehole annulus of each of the isolated zones by: opening a first valve at the port of the isolated zone with the workstring; sealing an outlet of the workstring at the port of the isolated zone, flowing slurry as the treatment down the workstring, out the outlet, and to the port, gravel packing the borehole annulus of the isolated zone with gravel in the slurry, filtering fluid returns of the slurry from the borehole annulus of the isolated zone into the through-bore of the assembly through the screen and through a second valve at the screen, preventing flow of the fluid returns in the through-bore from flowing back to the borehole annulus out the first and second valves (652, 645) of the other isolated zones on the assembly; and removing excess of the treatment from the workstring by: sealing the outlet from the open first valve of the port, reverse circulating down the through-bore of the assembly and into the outlet of the workstring, and preventing the reverse circulation in the through-bore from communicating to the borehole annulus through the first and second valves (645, 625) of the screens and the ports of the isolated zones. isolating a borehole annulus of the borehole around an assembly into a plurality of isolated zones, the assembly in each isolated zone having a port and a screen communicating a through-bore of the assembly with the borehole annulus; positioning a workstring in the through-bore of the assembly; treating the borehole annulus of each of the isolated zones by: opening a first valve at the port of the isolated zone with the workstring; sealing an outlet of the workstring at the port of the isolated zone, flowing slurry as the treatment down the workstring, out the outlet, and to the port, gravel packing the borehole annulus of the isolated zone with gravel in the slurry, filtering fluid returns of the slurry from the borehole annulus of the isolated zone into the through-bore of the assembly through the screen and through a second valve at the screen, preventing flow of the fluid returns in the through-bore from flowing back to the borehole annulus out the first and second valves (652, 645) of the other isolated zones on the assembly; and removing excess of the treatment from the workstring by: sealing the outlet from the open first valve of the port, reverse circulating down the through-bore of the assembly and into the outlet of the workstring, and preventing the reverse circulation in the through-bore from communicating to the borehole annulus through the first and second valves (645, 625) of the screens and the ports of the isolated zones. opening a first valve at the port of the isolated zone with the workstring; sealing an outlet of the workstring at the port of the isolated zone, flowing slurry as the treatment down the workstring, out the outlet, and to the port, gravel packing the borehole annulus of the isolated zone with gravel in the slurry, filtering fluid returns of the slurry from the borehole annulus of the isolated zone into the through-bore of the assembly through the screen and through a second valve at the screen, preventing flow of the fluid returns in the through-bore from flowing back to the borehole annulus out the first and second valves (652, 645) of the other isolated zones on the assembly; and removing excess of the treatment from the workstring by: sealing the outlet from the open first valve of the port, reverse circulating down the through-bore of the assembly and into the outlet of the workstring, and preventing the reverse circulation in the through-bore from communicating to the borehole annulus through the first and second valves (645, 625) of the screens and the ports of the isolated zones.