Is thatn the site just outside Abbeville. I am not at home and have not got my site book with me but it sounds familiar. If so, then we have used it 2 years in a row. It tends to be a bit shady and the electric may folow French fashion but it is a nice site for a stopover. You get delivered croissants in the morning if you so wish and they do remeber you from previous visits which is nice. The younger memebers of the team speak English although 'Madam' plays it. Out of the main season only 1 toilet block may be in operation, so get up early if you need to use the showers.
Cost was about 16 euros for the 2 of us and outfit if I remember
We use it to visit St valerie sur Somme, a lovely port only about 10 miles away.