The settlement was reached on July 27, after a third attempt by two judges serving on the state's Mass Litigation Panel. Three other judges had been simultaneously preparing to begin a series of trials on Aug. 1.
Initially, some 700 people sued Massey, claiming it contaminated their aquifer and wells by pumping 1.4 billion gallons of toxic coal slurry into worked-out underground mines between 1978 and 1987.
Slurry is created when coal is washed to help it burn more cleanly. The residents say it seeped out of the old mine workings and into their aquifer, turning their well water varying shades of red, brown and black, and causing ailments ranging from learning disabilities to cancer.
The letter also tells the plaintiffs that besides the medical monitoring program, they are eligible for a health benefits program. The details of how that will work are still being negotiated.
For decades, coal companies in Appalachia have injected slurry into worked-out mines as a cheap alternative to dams and other systems that can safely store or treat it. The industry claims underground injection is safe, but critics say slurry leaches into water tables through natural and man-made cracks in the earth.
The plaintiffs are now mostly served by a public water system, but they argue that chronic exposure to metals and chemicals are to blame for birth defects and other health problems.
The settlement letter says the medical monitoring plan will give the plaintiffs "a fighting chance against potential future diseases" and will be in place by year's end.
The letter also indicates that many plaintiffs are concerned the settlement could jeopardize their Social Security, Medicaid or Medicare benefits.
The attorneys say they're working on creating "special needs trusts," that could shield their settlement money and allow plaintiffs to use it for expenses such as clothing, automobiles or homes.
The plaintiffs will also get financial counseling so they understand the implications. Lien claims by Medicaid and Medicare, for example, must be cleared before funds can be distributed.
Still, the letter says, the goal is to distribute the money within 90 days.