Fifteen of the state's largest utility, mineral and transportation companies will get tax breaks from $130,000 to $5.2 million annually should voters approve the property-tax-limiting Initiative A, initiative opponents say.

And homeowners and small-business owners will subsidize those corporate tax breaks, which would total $24 million yearly, say state tax commissioners and Utah Association of Counties officials.But a spokesman for the Utah Taxpayers Association, the architects of Initiative A, said it's "patently false" for the Tax Commission to imply that corporations would get proportionally greater tax relief than would homeowners.

In a Wednesday press briefing called in response to news media requests to identify the relative winners and losers if Initiative A passes, officials named corporations that would gain a windfall from passage. (See accompanying chart.) The initiative would cap property taxes at 1 percent of fair market value, 0.75 percent for residential property.

Among the big winners: Utah Power & Light, which would save an estimated $5.2 million in taxes annually; Intermountain Power Agency, an estimated $3 million savings; Kennecott Copper, $1.7 million; Mountain Bell, $1.3 million, Mountain Fuel Supply, $1.3 million; Union Pacific Railroad, $730,000; and Delta Airlines, $300,000.

Those estimated savings are based on 1987 property valuations and tax rates compiled from public records on file with counties and the Tax Commission.

But Howard Stephenson, assistant director of the taxpayers association, said corporations would get bigger tax cuts from Initiative A because they pay more taxes.

"Initiative A gives the same proportional cuts to all property owners, regardless of whether they are big business or a residential owner," Stephenson said. "If they pay 10 percent of the tax in one county, they will get 10 percent of the cut."

These companies named are not necessarily the state's biggest taxpayers or the corporations that would stand to save the most money from passage of Initiative A, said Brent Gardner, association of counties executive director.

But they are among the 15 largest corporations that have the value of their property assessed directly by the state - rather than by local counties as homeowners, small-business owners and other corporations do.

Gardner said it should be understood that the corporations named did not initiate or request the tax breaks that Initiative A would give them. Some of those companies are actually opponents of the initiative, he said.

Passage of Initiative A would shift a greater portion of the tax burden from state-assessed utility, mineral and transportation companies to the locally assessed homeowners and small-business owners, tax commissioner Roger Tew said.

Under current law, the fair market value - the value on which property taxes are assessed - of locally assessed property, both residential and commercial, is 80 percent of the property's actual value.

Initiative A would make fair market value of locally assessed property 100 percent of actual value, eliminating the 20 percent allowance, Tew said.

Initiative proponents dispute the tax commission's interpretation of fair market value under the initiative. They maintain fair market valuation would be unchanged by passage of the measure, with the 20 percent allowance left intact.

Using the tax commission interpretation, the automatic 20 percent increase in valuation of locally assessed property in some cases would more than offset the tax rate reduction property owners would get if the initiative passes.

The result in those cases would be an actual property tax increase, rather than the tax relief promised by initiative proponents, Tew said. In other cases, property owners would see a slight tax decrease, perhaps as little as $6 annually.

The impact passage of Initiative A would have on individual homeowners depends on where they live, the value of their home and which interpretation of fair market value is used.

Big winners

These businesses would benefit most from passage of Tax Initiative A. Their annual estimated tax savings are also listed:

UP&L $5.2 million

IPA $3 million

Kennecott $1.7 million

US WEST $1.3 million

Mountain Fuel $1.3 million

Union Pacific $730,000

Delta Airlines $300,000