A third group is withdrawing its support of Public Service Co. of New Mexico's plan to shut down half of the coal-fired San Juan Generating Station near Farmington.
Western Resource Advocates notified state regulators in a filing Thursday it could no longer support the plan.
The group was one of several organizations that signed off on a settlement agreement last October to back the plan to replace the electricity that would be lost by the closure of two units at San Juan.
Energy Industries Association and New Mexico Independent Power Producers backed out last week over concerns about the costs of PNM's plan.
Attorneys with Western Resource Advocates say they're concerned the utility or one of its affiliated companies could end up acquiring additional coal power to fill the gap.
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