May this helps
CREATE TABLE BCounts
(ID INT IDENTITY,Bcon VARCHAR(10), Val1 INT, Val2 INT)
INSERT BCounts VALUES('OC',1,1),('BC-a',4,5),('BC-b',2,3),('BC-c',1,2)
SELECT LEFT(B.Bcon,2) Col1, SUM(B.Val1) Col2 ,SUM(B.Val2) Col2 FROM BCounts B
GROUP BY LEFT(B.Bcon,2)
Col1 Col2 Col3
BC 7 10
OC 1 1