Use a DELETE in batches.

DECLARE @i int = 1

WHILE @i > 0

BEGIN

DELETE TOP (1000000) work.dbo.WRK_FACT

where month >= @I and year = @year

SET @i = @@ROWCOUNT

BEGIN END

Or if you have a trigger on the table that might alter @@ROWCOUNT value.

WHILE EXISTS (

SELECT TOP 1 1

FROM work.dbo.WRK_FACT

where month >= @I and year = @year

)

BEGIN

DELETE TOP (1000000) work.dbo.WRK_FACT

where month >= @I and year = @year

BEGIN END