Transaction Log 16GB on 2MB database
Was the database in FULL recovery but no backups being taken previously? Paul Randall's article Running Out of Transaction Log Space covers the other likely scenarios.

The DMV query below will tell you why the log cannot be truncated. If you're unsure how to interpret the output, add the response to your question.

SELECT
    db.[name] AS [Database Name]
  , db.recovery_model_desc AS [Recovery Model]
  , db.log_reuse_wait_desc AS [Log Reuse Wait Description]
  , ls.cntr_value AS [Log Size (KB)]
  , lu.cntr_value AS [Log Used (KB)]
  , CAST(CAST(lu.cntr_value AS FLOAT) 
    / CAST(ls.cntr_value AS FLOAT) AS DECIMAL(18,2)) * 100 AS [Log Used %]
FROM
    sys.databases AS db
INNER JOIN
    sys.dm_os_performance_counters AS lu
ON  db.name = lu.instance_name
INNER JOIN 
    sys.dm_os_performance_counters AS ls
ON  db.name = ls.instance_name
WHERE
    lu.counter_name LIKE N'Log File(s) Used Size (KB)%'
AND ls.counter_name LIKE N'Log File(s) Size (KB)%'
AND ls.cntr_value &gt; 0
OPTION (RECOMPILE);