Construction has begun on one of the largest single-family home developments in the Salt Lake area in recent years.

Work got under way this week on the first phase of what developers OMN Development Corp. say will be a 250-lot single family home community at 2590 E. 7000 South on land that formerly housed the 117-acre Monroc-Cottonwood gravel plant.With the groundbreaking for the development, the gravel plant has closed after 42 years of operation. The developers said Monroc is scheduled to cease active rock crushing operations at the site by the end of this year.

Christopher K. McCandless, a partner in the development firm, said the complex will be called Mill Hollow Estates and will include a 26-acre park.

Construction of the complex is planned in seven phases with completion of the last phase expected by 1996.

The site is just below the Mill Hollow Ridge subdivision, a 42-lot single family subdivision that OMN also developed and which sold out to various home builders in less than a year. The new project is also located just to the west of Old Mill Estates, the single-family community that was the site of this year's Parade of Homes.

Phase 1 will be located immediately west of Mill Hollow Ridge subdivision and will be accessed from 7000 South. Following phases will be located to the south - all the way to 6485 South - and to the east at the base of the ridge and to the south of the planned park.

McCandless said first-phase construction of houses at Mill Hollow Estates is expected to begin as early as November with the second phase set for launch next spring.

Development of Mill Hollow Park, which sits at the base of a steep gravel ridge immediately below Mill Hollow Ridge subdivision, "will require extensive planning and interrelated involvement between the public, community councils and Salt Lake County government," said McCand-less.

He said the preliminary plan for the park is currently being scrutinized by various government entities and construction is not expected to get under way for two or three years.

OMN has plans for extensive grading, reclamation and landscaping to be completed with each of the seven development phases of Mill Hollow Estates, said McCandless. As part of the revegetation plan, he said OMN and the various homebuilders in the development intend to plant 50-60 trees during each phase of construction.

Additional common landscaped areas will include "an impressive entrance," said McCandless, incorporating the old Monroc stone wall located at 2590 E. 7000 South.

McCandless said the development will offer unobstructed city views, close proximity to the new I-215 interchange at 6200 South and 2900 East and to the Cottonwood Heights Recreation Center and the nearby canyon/ski areas.

Negotiations between the buyer and seller were handled by Mansell and Associates through Ken Schef-ski. Marketing of the complex is also being handled through Mansell and Associates.