The conclusion was found in a consultant's report released Monday by the county. The report, presented by The Brendle Group of Fort Collins, capped a three-month survey to identify the sources and levels of greenhouse gases. Findings are based on 2005 as a baseline year.

But an accompanying letter by Christi Zeller, executive director of the La Plata Energy Council, said the study so distorts the reality of her industry that it should be discarded or completely revised.

"We believe the Climate Mitigation Services report to The Brendle Group for the natural-gas industry emissions is so flawed that it must be completely revised or simply precluded from being used," Zeller said. "We suggest partnering to create a protocol with other regional initiatives - notably the Western Climate Initiative - and working to construct a credible inventory."

Zeller said the report extrapolates from New Mexico emissions to calculate La Plata County statistics. The regions produce the same gases, but the chemical compositions are different, she said. Calculations aren't specific to La Plata County.

Zeller's appeal to eliminate Appendix • related to specific emissions of the natural-gas industry was honored. In its place is a single-sheet statement by Erick Aune, the county's director of community development, saying that the county and the energy council will work together to derive greenhouse gas estimates that more accurately reflect the behavior of the natural gas industry in La Plata County."

Greenhouse-gas inventories give governments and policy-setting agencies a basis to calculate trends and develop strategies to reduce greenhouse-gas emissions. Since 1990, the federal Environmental Protection Agency has maintained an annual greenhouse-gas inventory.

The Brendle Group report estimates that total greenhouse-gas emissions in La Plata County by industrial and related sources is the equivalent of slightly more than 5 million tons of carbon dioxide. Natural-gas production is responsible for 2.47 million tons, industrial energy use (mainly the natural-gas industry) accounts for 1.2 million tons and all other uses, 1.3 million tons.

Among the sources of the 5 million tons are natural-gas production, mining and agricultural activities, on-road and stationary fuel consumption, solid waste disposal, railroads, wastewater treatment and medical waste incineration. The on-road and stationary category included greenhouse gases from vehicles.

It's calculated that emissions from natural-gas production and energy use will decrease to a little more than 3.5 million tons by 2020, mainly because of reduced production of natural gas. The 1.3 million tons of carbon dioxide equivalent attributed to all other sources will increase to 2 million tons in 2020.

Patrick Cummins, director of air quality and climate programs for the Western Governors Association, said the report is a good first effort. Emission inventories are fraught with uncertainties, he said.

But, Cummins said, while all data is included in the initial part of the report, it inexplicably is not used in all calculations. He cited the three categories of emissions used early in the report - followed by the caveat that from then on references to total La Plata County greenhouse-gas emissions would include only the energy-use segment and the "all other" category.

The omission of the category for the amount of natural-gas production emissions in ranking La Plata County with other areas, skews the results, Cummins said. The report says La Plata County emits the equivalent of 52 tons of carbon dioxide per capita, compared with 28 tons per capita for Colorado as a whole, 18 tons per capita in Boulder County and 29 tons per capita in Denver.

If the emissions of natural-gas production were counted, La Plata County would emit double the 52 tons per capita cited in the report, Cummins said.

daler@duangoherald.com