I just put my baby daughter down in the garden and saw two 'drill' holes in the lawn (patchy). They each had a tiny pile of earth shovelled outside and I saw a wasp crawl in (the hole was wasp sized). The wasp was then 'waiting' at the entrance, and I saw another wasp hovering nearby. Is this a wasp nest? I'm alarmed as I not only put my daughter down there earlier and didn't notice, but we have friends with small children coming for the weekend. Is there anything I can do? Are there likely to be more or would they be together? Thank you!
Sounds like it could be a nest - have a look (from a distance) at midday when it's more likely to be sunny. However as a precaution. you can buy some wasp killer (powder form) from homebase or similar.
Go out at night time (so wasps are not active) and sprinkle carefully around and in the holes. Don't inhale the powder. After 24-48 hours the wasps should take the powder into the nest (it'll brush on them) and kill the lot). In the mean time, stay out of the garden and check once the sun has gone down.
We had a wasp nest in our compost bin and did this. Worked well and cheaper than getting someone from the council out - just be careful.