PNM: Closer look at coal silo collapse is not necessary

Further probing into the collapse of a coal silo in March that put a power generating unit temporarily out of commission is unnecessary, the Public Service Company of New Mexico argued in a filing Tuesday.

Corrosion and a faulty weld holding two sections of the silo together were at fault for the collapse March 17 at the San Juan Generating Station near Farmington, which released 614 tons of coal, according to PNM. Coal dust in the falling coal exploded, damaging nearby equipment associated with the No. 1 power-generating unit, one of two in service at the plant.

No one was injured in the incident, but damage to the generation unit amounts to between $15 million and $20 million in repair costs, according to PNM.

The electric utility reported the damage in a filing required in April by the New Mexico Public Regulation Commission. Nine advocacy groups led by New Energy Economy, a Santa Fe-based organization that advocates for reduced use of power generated by nuclear plants and fossil fuels, petitioned the commission in April to force PNM to explain the cause behind the incident and justify its repair costs.

PNM argued that opening a formal investigation into the collapse would delay repairs and possibly add to customers’ bills the cost of finding power elsewhere to meet demand.

New Energy Economy in its petition April 12 argued PNM could use the collapse to make costly improvements to the unit and argue later for increasing consumer rates to pay for them.

PNM, which splits ownership of unit No. 1 with Tucson Electric Power Co., said insurance will cover most of the repair costs. The PNM share of the deductible comes to $1 million, according to its filing.

“It is clear that the most effective path forward is to complete the repairs to the damaged unit and get it back into service,” PNM spokesman Dan Ware stated in an email Tuesday. He said PNM during the outage is doing scheduled maintenance on the unit, which should be back in service in June.

Mariel Nanasi, executive director of New Energy Economy, on Wednesday said she had not seen the PNM response and would not comment.