Sigma Delphi

Description of Site
The Sigma Delphi binary white dwarf system's innermost planet is an ice world with methane oceans and a great deposit of woznium, a super-dense element used principally in warp core reaction chambers. Its eccentric orbit periodically takes it between the binary stars’ orbit. The materials interact with the tremendous gravitational forces and generate a spur of space-time curvature that that extends out into passing space lanes. Discovered by the Lexington in 2322.Q1.M1.

Other Notes
The mining site will have to be periodically abandoned whenever the planet's orbit takes it between the binary stars, something that fortunately occurs only every 5.2 years or so and for a period of 3 months (including safety margin). Not that anyone will be too sorry to leave an ice world with methane oceans; there's nowhere to go and nothing to do but hang around the hab-domes when you're off-shift.