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We study the late-time (t>0.5 days) X-ray afterglows of nearby (z<0.5) longGamma-Ray Bursts (GRB) with Swift and identify a population of explosions withslowly decaying, super-soft (photon index Gamma_x>3) X-ray emission that isinconsistent with forward shock synchrotron radiation associated with theafterglow. These explosions also show larger-than-average intrinsic absorption(NH_x,i >6d21 cm-2) and prompt gamma-ray emission with extremely long duration(T_90>1000 s). Chance association of these three rare properties (i.e. largeNH_x,i, super-soft Gamma_x and extreme duration) in the same class ofexplosions is statistically unlikely. We associate these properties with theturbulent mass-loss history of the progenitor star that enriched and shaped thecircum-burst medium. We identify a natural connection between NH_x,i Gamma_xand T_90 in these sources by suggesting that the late-time super-soft X-raysoriginate from radiation reprocessed by material lost to the environment by thestellar progenitor before exploding, (either in the form of a dust echo or asreprocessed radiation from a long-lived GRB remnant), and that the interactionof the explosion's shock/jet with the complex medium is the source of theextremely long prompt emission. However, current observations do not allow usto exclude the possibility that super-soft X-ray emitters originate frompeculiar stellar progenitors with large radii that only form in very dustyenvironments.

Dust in the wind: the role of recent mass loss in long gamma-ray bursts