Yeah, I thought it was unlikely, but the way they phrase it on their website makes it seem like they accept BTEC L3 Applied Science by itself:
"Our requirements for an applicant taking BTEC qualifications would typically be:
BTEC Level 3 Extended Diploma in Applied Science (to include units in Inorganic Chemistry and Organic Chemistry)
BTEC Level 3 Diploma in Applied Science (to include units in Inorganic Chemistry and Organic Chemistry) plus 1 A-level
BTEC Level 3 Foundation Diploma in Applied Science (to include units in Inorganic Chemistry and Organic Chemistry) plus 2 A-levels (one of which must be Biology, Physics or Mathematics)
BTEC Level 3 Extended Certificate or Subsidiary Diploma in Applied Science plus 2 A-levels (one of which must be Chemistry)".
It's just the way they make provisions for the Foundation Diploma, saying you have to take biology as well, which I assumed would already be a requirement, as you say.
The way they phrased it threw me off.