A dozen Maryland and District citizen groups plan to attend a D.C. Zoning Commission hearing today to protest a development proposal that could permit more intensive commercial growth in the Friendship Heights area.

The hearing will be held at 1 p.m., in Room 11-A of the District Building, 1350 E St. NW. The citizen groups are expected to testify against phase two of the Friendship Heights sectional development plan, claiming that it will lead to encroaching commercialism in residential neighborhoods, greater air and noise pollution and more traffic on already congested streets. Phase two was drafted by the D.C. municipal planning office.

"This is the final battle," said John Engel, head of the Friendship Neighborhood Coalition (FNC), which has led a six-year fight to assure that the area's development is compatible with neighborhood values. Friendship Heights includes the intersection of Western and Wisconsin Avenues, long considered by developers as one of the nation's prime commercial sites.

After an FNC meeting last week, Engel said he was "sort of pessimistic" about defeating phase two, which deals with elements such as traffic patterns, buffer zones between commercial and residential properties and density. The FNC feels that the municipal planners' draft favors developers and that the zoning commissioners disregard residential interests in an effort to bring more business into the city.

Engel said his group has widespread citizen support, however, and that representatives from areas like Capitol Hill, Georgetown and Chevy Chase Village, Md., planned to testify in the FNC's behalf today.

City council member Polly Shackleton of Ward III told the group that "it will be impossible to live pleasantly in this area" if the draft proposal is approved. She said the FNC had the support of "so many other citizen groups because the city made a commitment, then turned around and backed off."

The consensue of the FNC was that in drafting phase two, the city had violated the intentions and spirit of the original sectional development plan.

The two-part plan was first proposed in 1973 by cooperating citizen and government groups in the District and Maryland to assure balanced growth that would protect the integrity of residential neighborhoods. Phase one was approved by the zoning commission in 1974 and, in a victory for the FNC, the area's heavily commerical areas were "downzoned" to both residential and commerical zoning.

A hearing on phase two was held in December 1975 but no decision was reached. The muncipal planning office drew up another phase two plan in 1976, but it was unsatisfactory to both residents and developers.

Former FNC president Helen Woods last week scored the District . . . All the work over the years is thro Friendship Heights, the cooperation between Maryland and the District . . . . All the work over the years is thrown on the historical scrap heap."

Calling the draft a "deceptive document," Woods said that, for example, the original version required buildings to be set back "a minimum of 10 feet" from the street to allow the wide sidewalks and plantings. The new version, she said, "crossed all that off and put in 'up to 10 feet.' So if you have 11 feet, you're in violation."

Woods said the new 60-store Mazza Gallerie was allowed to substitute "arcaded interior space for setbacks," disregarding intentions of the sectional development plan. "The Mazza was built to their (the city planners) specifications for the future. I can't exactly prove it but the standards didn't fit before, so they fixed them to fit," she said.

By putting so many commercial properties in Friendship Heights, "it is much more difficult to revitalize downtown. And they (the planners) don't consider what all the traffic jams will do to the retailers here," Woods said.

Traffic generated by the area's growth has been a central concern of the FNC. Margaret McDermott, head of the group's transportation committee said her calculations showed that if development were permitted to achieve the levels suggested in the phase two draft, resulting traffic volume "would reach the E level, just one stop below a parking lot. Traffic would move at 15 miles an hour."