Milk Hill and Milk Hill White Horse are owned by Natural England. Natural England requires £5 Million third party insurance cover to access these sites. A list of BHPA members with appropriate insurance cover is available on the TVHGC website. If you DO NOT have this level of insurance cover YOU are not allowed to fly on either of these sites. As a member of the BHPA you should have the appropriate cover however it's your responsibility to check.
For visiting pilots flying with a IPPI card must also have third Party Liability Insurance up to £5 Million. You can also find details here: http://www.bhpa.co.uk/sport/bhpa/visiting_pilots.php