A director of the Alameda County Transit District in Oakland has apologized for using a district credit card to charge more than $4,000 in purchases since 1986. "My conduct . . . was inexcusable," Linda Shepard, a director representing the Fremont area, said about her purchases of clothes, records, a manicure and hairdo, rental car and other items. She has since paid for all her personal expenses. Lawrence Rosenberg, district secretary, said he should have examined more closely bills for $427 worth of clothing for Shepard. The items appeared on her expense forms as dinner or lunch costs. Rosenberg said he tried to persuade district officials to use public funds to pay off Shepard's $3,381 balance last month because he and accountants could not agree how much money she owed. "She promised us that she would pay the district back as soon as we determined how much she owed. No one had any malicious intent," he said.