As organizers pledged to open Herndon's site for day laborers by November, angry officials in neighboring Loudoun County threatened yesterday to use zoning laws to block the town's decision to build it.

Two Loudoun supervisors whose residential districts abut the hiring center -- which was approved Wednesday night by the Herndon Town Council -- accused Herndon leaders of circumventing them in a decision that they said will affect their constituents. The 12-acre property on Rock Hill Road where Latino workers will wait for construction jobs sits along the town-county border.

"All they did was take the problem from downtown Herndon and put it in Loudoun," Supervisor Stephen J. Snow (R-Dulles) said, referring to the unruly gathering of workers each day at a 7-Eleven that the town hopes to replace with a formal, carefully monitored site. "We feel there was not adequate cooperation and coordination" from the Town Council, he said.

Snow and Supervisor Eugene A. Delgaudio (R-Sterling) said yesterday that they believe their nine-member board would oppose the site if it were to come to them for a vote.

The site, at Rock Hill and Sterling roads, is flanked by townhouse developments.

Several dozen Loudoun residents testified against a designated gathering spot during two nights of hearings this week. The Town Council voted 5 to 2 to approve the site and use $175,000 in public money to create it.

Many of the day laborers are immigrants in the United States illegally. Council members said that although they do not sanction illegal immigration, they feel a responsibility to resolve a community quandary over where the workers should congregate.

Officials with Project Hope and Harmony, the social services agency that received a permit to build and operate the hiring hall, said they hope to have the center running in 90 days. A bilingual staff will oversee the workers and offer English classes at the center, which will operate from 6 a.m. to 11 a.m. weekdays and 7 a.m. to noon weekends. No more than 150 workers will be allowed on the property at once. The town specified that prospective employers -- the majority of them construction contractors -- must be notified that hiring undocumented workers is illegal. But Project Hope leaders said they do not plan to ask the workers to reveal their immigration status.

The leaders acknowledged that they must win over many skeptics in Herndon and Loudoun and said that they will not be an isolated presence in the community.

"We want to reach out to those neighborhoods close to the site and reassure them that we respect what they have said," said Joel Mills, a member of Project Hope and Harmony's executive board. "We are going to make some strong efforts to address traffic, nuisance and crime issues."

But the pledge did not placate Loudoun officials, who said they are reviewing the permit approved by Herndon to determine whether the site needs zoning approval from the county. Loudoun Zoning Administrator Melinda Artman has said that using the property for a day laborer center would require a county permit.

Herndon officials said they will offer to use Sterling Road in town, rather than Rock Hill Road in the county, as the way in and out of the site. Mayor Michael L. O'Reilly said the day laborers would congregate on less than a half-acre of the land.

"I'm not concerned about the viability of the project," O'Reilly said of Loudoun's opposition. "I do hope that Loudoun does not take steps to cause their relationship with us to deteriorate."

Virginia gubernatorial candidate Jerry W. Kilgore (R) jumped into the debate over day laborers this month, saying he opposes public funding for any activity that would help people in the United States illegally. His campaign reiterated those concerns yesterday in response to the Herndon decision.

The issue continued to divide Herndon residents. Some said they were relieved to see the town finally address their worries about the scene at the 7-Eleven, even as they described uneasiness with the workers' legal status.

"Our police, our towns and our cities have to help them understand that certain behavior is acceptable and certain behavior is not," Laury Blakley, a legal assistant who lives in Herndon, said of the workers. "The reality is most of them come here to do work that most Americans will not do" at much lower pay, she said.

Christy Bull, a town resident for 26 years, said the council had little choice but to set up a formal gathering spot. "There's nothing we can do outside of creating a site for them. . . . Either we create an official site for them to hang out, or they'll hang out on the corner."

Jose Rivera, 28, a day laborer who has lived in Herndon for two months and is a regular at the 7-Eleven, said he is elated by the town's decision.

The center "is going to be much better than here," Rivera said outside the store.

Dennis and Mary Drum of Herndon, who live next to the site of the planned day labor center, attend the final hearing before the vote on the permit.Sarah Ince, left, Elizabeth Hagg, Ellen Kaminsky and Joel Mills rejoice after the Herndon Town Council voted 5 to 2 to approve the day labor center.Said Hmamoch, 25, who works near the 7-Eleven, said he agrees with the decision to allow the site. The 12-acre property on Rock Hill Road where workers will gather is near the county line. Two Loudoun supervisors say county approval might be needed.