27924 Seco Canyon Rd Santa Clarita, CA 91350. Phone: 661-513-2100. Hours: Mon-Fri: 8 a.m. - 5 p.m. Special priority lab hours for senior patients: 8 a.m. - 10 a.m. Extended hours for pediatric patients: 2nd & 4th Tuesday of each month until 7 p.m..