We present compact three-generation F-theory GUT models meeting in particular
the constraints of D3-tadpole cancellation and D-term supersymmetry. To this
end we explicitly construct elliptically fibered Calabi-Yau fourfolds as
complete intersections in a toric ambient space. Toric methods enable us to
control the singular geometry of the SU(5) GUT model. The GUT brane wraps a
non-generic del Pezzo surface admitting GUT symmetry breaking via hypercharge
flux. It is contractible to a curve and we demonstrate the existence of a
consistent decoupling limit. We compute the Euler characteristic of the
singular Calabi-Yau fourfold to show that our three-generation flux solutions
obtained via the spectral cover construction are consistent with D3-tadpole
cancellation.Comment: 22+12 pages; v2: minor clarifications on decoupling limi