The age of some San Dieguito artifacts at the C. W. Harris Site is shown stratigraphically to be older than 9,030 (11,222 to 9,322) B.P. The artifacts associated with dates of 8,490 (10,561 to 8,540) B.P. may have been redeposited with the gravel and sand in which they were found, and may be older than 8,490 (10,561 to 8,540) B.P. The San Dieguito-bearing deposit, Stratum E, is divided into three Units: EI, EII, and EIII. EI contains undisturbed San Dieguito artifacts and features located in coarse and ne sands overlaying gravel and sand deposits. Unit EII is composed of the fill of Channel 1, which cuts through the undisturbed San Dieguito level in Unit EI. Channel I ll consists of gravel and sand strata containing redeposited San Dieguito artifacts. A radiocarbon date of 9,030 (11,222 to 9,322) B.P. was obtained from a stratum in coarse sands overlying the stream deposits of Channel 1. Unit EIII is Channel 2, cut into the edge of Channel 1 in Unit EII. The boundary between EII and EIII is an erosion surface which rises toward the east, just 20 cm. above the location where the date of 9,030 (11,222 to 9,322) B.P. was obtained. Channel 2 was cut to bedrock and lled with three gravel and sand strata containing San Dieguito artifacts. Two dates of 8,490 (10,561 to 8,540) B.P. were obtained on charcoal from the middle stratum. Warren and True (1961) believed a charcoal lens from this stratum was a hearth, evidence of human occupation at 8,490 (10,560 to 8,540) B.P., but this now seems unlikely. The San Dieguito occupation at the C. W. Harris Site began sometime prior to 9,030 (11,222 to 9,322) B.P. and may have persisted to ca. 8,540 (10,561 to 8,540) B.P.