Faced with a 10 percent surge in enrollment and the opening of four new campuses, Loudoun County public schools must have 400 additional teachers on board before school resumes next month.

School officials already have hired 332 full-time teachers and plan to hire 60 more in the next month. New teachers--almost all of them licensed in Virginia--are due to report for orientation Aug. 17, said Matthew D. Britt IV, assistant superintendent for personnel services, who said he expects to fill nearly every job opening before then.

"Normally, we're down to about eight vacancies by then," he said. "This year, it may be even less."

Last year, Loudoun received 2,222 applications and hired 373 teachers. The number of applicants for the upcoming school year hasn't been tallied.

Britt recalled that when he joined the growing Loudoun school system in 1992, his boss warned him about the work that lay ahead: " 'I don't know how you're going to do it. We've never hired this many teachers before,' " Britt said he was told.

That year, he needed to fill 83 positions.

Seven years later, the number has increased fivefold, applications are scanned on computer and some members of Britt's staff travel as far away as California and Texas in search of great teachers.

One new teacher, Amy Harris, said Loudoun was the only school district to which she applied. After her parents moved from Minnesota to Lincoln about two years ago, she heard reports of the county's stunning growth while she was getting a master's degree in elementary education at the University of Minnesota.

"My first response was, 'They've got to be hiring,' " said Harris, who worked in a Minneapolis brokerage firm before returning to school. "Then it was the opportunity to be living near my parents."

Harris, who will be teaching fifth grade at Cool Spring Elementary School in Leesburg, said she also thought that the school district must be good if so many young families are moving to Loudoun.

Britt said Loudoun's rapid growth helps school officials attract teachers, who have more career opportunities in an expanding district that continually builds new campuses.

"In lots of school districts, it's very stable, and there is little turnover," Britt said. "Here there is constant movement."

The third fastest-growing school district in the nation and the fastest in Virginia, Loudoun schools will enroll an estimated total of 29,000 students in the 1999-2000 school year, up from 26,000 students last year.

Four new schools will open next month: Cedar Lane Elementary in Ashburn, Horizon Elementary in Cascades, Round Hill Elementary School and Harper Park Middle School in Potomac Station in Leesburg. About 49 new teachers will be hired to staff those schools, and 87 current teachers will transfer to the new campuses.

Loudoun's need for teachers is expected to only increase. County officials have said they need to build 22 schools during the next six years to accommodate the additional students.

Neighboring jurisdictions also are feeling the pressures of a teacher shortage. About 1,600 new teachers will join Fairfax County public schools in September. D.C. public schools need to hire 1,100 full-time instructors, and in Prince George's County, 1,300 new teachers are needed.

Several hard-to-fill subject areas include advanced math and science, special education and tech education (once known as industrial arts). Minority applicants, particularly Asians and Latinos, also are in high demand as the school district seeks to create a more diverse group of instructors.

But the biggest obstacle to hiring teachers in Loudoun is pay, some officials said. The county's starting salary for a beginning teachers who has a bachelor's degree is $29,038--the lowest among all Northern Virginia school districts.

Some seasoned Loudoun teachers are quitting to teach in Fairfax County public schools because of the higher pay scale there--although administrators do not have an exact count of how many teachers they lose. For some teachers, moving to Fairfax would mean a raise of as much as $10,000.

"We need to be completely competitive, I believe, with Fairfax from the top of the scale to the bottom of the scale," said Loudoun Superintendent Edgar B. Hatrick III.

Hatrick and Britt both said they plan to lobby the School Board and the Board of Supervisors for higher teacher salaries and a separate pay scale for teachers who have doctorate degrees.

The brunt of hiring has fallen especially on principals of the four new schools, who must build a staff from scratch.

In the last few months, Horizon Elementary School Principal William Raye has hired 17 teachers--a mix of beginners and experienced instructors. Twelve more teachers have transferred from other Loudoun campuses.

"It was time-consuming, to say the least," he said. The last hire accepted Raye's job offer Wednesday.

But he said he feels confident that he can take pride in his new staff.

"I didn't look at this as being a hurdle," Raye said. "I knew that this was going to be part of" opening a new school.