Renaldo Nehemiah continued his assault on the record book today in the sixth annual United States-U.S.S.R. junior track and field meet at the University of Richmond.

The 18-year-old Scotch Plains, N.J. hurdler, who will attend the University of Maryland this fall, clipped 0.4 seconds off the meet record with a blazing 13.5 clocking in the 110-meter high hurdles.

Unfortunately, the Accutrack automatic timing device malfunctioned, depriving Nehemiah of another record. Two weeks ago, he set an automatic-timed mark of 13.89 in the U.S. Junior Nationals in Knoxville, Tenn.

The soft-spoken Nehemiah was not disappointed. "I just wanted to win," he said. He had four yards to spare on runner-up Dan Lavitt of Kansas City, Mo.

Nehemiah hit at least three hurdles en route to his 13.5. "I wasn't concentrating on that as much as I was on what I did between hurdles," Nehemiah said. "I wanted to make sure I took 2 1/2 steps between so I could attack each hurdle."

In today's early events, the U.S. swept the men's 100 meters and the women's 100 meters and 400 meters. Randy Smith of Jackson, Mich., and Stanley Young of Detroit went one-two in the men's event in 10.55 and 10.76, respectively.

Val Boyer of Albuquerque, N.M., and Kim Robinson of Los Angeles were hand-timed in 11.3 and 11.4 for first and second place in the women's 100. Edna Brown of Philadelphia and Marian Franklin of San Francisco ran 54.65 and 54.91, respectively, in outdistancing their Soviet counterparts by 10 yards.

The U.S. men picked up another sweep in the 400 meters as Baltimore's Keith Brown, a Villanova freshman, overtook Anthony Tufariello, a Villanova frosh-to-be, in the final straightaway to win in 46.6 (hand timed). Tufariello, who is from Hewlett, N.Y., clocked 46.9.