Ten years ago, Questar Gas Co. began adding radio transponders to its meters so they could be read remotely. Installation was completed two years ago. Unfortunately, there were avoidable errors.

Transponders could be installed so they would report exactly half the gas used. A few were. And actual meter readings could have been compared with transponder-reported numbers. Apparently that didn't happen until June and July 2007, when Questar checked 26,000 meters and found problems with 22. In November 2007, new software was loaded on computers in the 20 meter-reading trucks, identifying undermetering of about 500 customers.

Questar sent out bills asking them to pay for the difference for periods ranging from a few months up to two years. The bills varied from $30 to $7,000 and averaged $1,000, for a total of $500,000.

People weren't happy. It was hardly their fault that they had been underbilled. Some were in new homes, others had installed new furnaces or insulation or had other reasons to think their bills were reasonable. If they had received accurate bills all along, they could have trimmed their usage; too late now.

(Supermarket managers don't chase customers into the parking lot for the difference if an item is undercharged at the checkout. They want you to come back.)

The way Questar's rates are set raises another hackle. About 73 percent of our bill payments are for the actual gas the company delivers to us (the rest is infrastructure, labor, etc.). That money goes on one side of a balancing account; what Questar spends to buy the gas goes on the other. As gas costs and revenues rise and fall, rates are adjusted to keep the account in balance.

If revenues from 500 customers are short because of undermetering, rates for all 874,000 customers go up very slightly. It's reasonable to suppose that a small proportion of transponders have always been incorrectly installed; maybe for 10 years we've all been paying a bit more to compensate for Questar's failure to manage this program effectively.

If a transponder can transmit half the actual consumption, might it not be able to transmit double? Could there also be hundreds of customers who, over the past 10 years, have been billed for twice the gas they actually used?

It needs investigation.

The Public Service Commission is going to kick one off at 9:30 a.m. on Thursday, April 17, with a procedural conference to discuss the scope and time of the investigation and the manner and timing of adjudicating individual complaints.

To participate, come to Room 403, fourth floor, Heber Wells State Office Building, 160 E. 300 South, Salt Lake City, or call 801-530-6716 (toll-free 1-866-772-8824) at least two days before to obtain a call-in number.

The Utah Ratepayers Association has asked to be allowed to participate in the investigation. We want to help individual ratepayers navigate the commission's arcane processes and ensure that everybody gets a fair deal eventually. We invite you to contact us if you received a back-bill due to a faulty Questar transponder or if you are concerned that you may have been overcharged over the past 10 years.

E-mail us at [email protected] or call 801-998-8511.

Roger Ball, former director of the Committee of Consumer Services, is moderator of the Utah Ratepayers Association.