Moving to the area... advice on 'ground heave' rating in environmental search

Hello everyone,

I'm in the process of buying a place on Hampden Road and I'm really, really excited about it. I've been looking all over London but I've had my heart set on north (my family live a few stops up the train line). So when this place came up I couldn't believe my luck: the flat is lovely, the area is great and the price is... well... just about doable.

But - I've just had the environmental search returned and it's raised a potential problem: it's received a 'moderate' rating for 'potential for natural ground instability in the area within 50m of the property.' The rest of the information in this section is frustratingly ambiguous and basically recommends purchasing a further search or contacting a structural engineer.

So I was wondering - has anyone else in Hampden Rd/the nearby area experienced the same rating when buying? Past experience with subsidence issues has made me less jumpy and increasingly skeptical about 'potential' ratings such as this, but it's also taught me that if I go down the route of engaging a structural engineer it can make it really difficult to take out insurance in the future. 

I'd be really grateful if anyone with a similar experience would be prepared to share it with me, and/or offer any advice.

Many thanks in advance.