Drain help!

[PiafPilaf]

This photo is of our hopefully-soon-to-be pantry. It now opens onto the new kitchen extension but when the house was built (1930s) it was an external cupboard. When we moved in it was used to house the washing machine, and the waste went into the hole near the back wall in the photo.

It all smells a bit damp but doesn't look any worse now than when we moved in so I'm hoping it was historic. Can we block up the hole? What do we need to do to it? Any ideas welcomed - thank you!

[BennyTheBall]

Yes, you can block the hole.

Is there any ventilation in there? Window, air brick?

[PiafPilaf]

No none at all. Presumably it didn't need any when built as it was an outside cupboard.

[PiafPilaf]

Hmm.... Spare bit of vinyl we put down 2 years ago is mouldy underneath too.