Check EPAs web site for suggestion on cleaning up mold. More important stop future growth of mold in your crawlspace. Monitor the %RH in the crawlspace during the high moisture time of the year. A $15 %RH electronic meter will work. If the %RH is above 60% when warm wet outside, you must lower the humidity in the space. Plastic vapor retarder on the earth and closed vents is a start. Dehumidification may be necessary depending on the outdoor conditions.