It's a total headache to get to but the best way is to take line 13 to Xierqi station. From there, try to hail down a cab to take you there and ask him to wait for you. I've done this before and the driver was willing to wait. However, I've also been during rush hour when there weren't any available legal cabs and ended up getting a black cab. It cost me 15 kuai each way and he also waited for me but you need to be able to speak Chinese.

The other way to get there is getting bus no. 333 to Xialinyuan 夏霖园 and from there walk west for 150 metres. Look out for the grey building that says 中国检验检疫。