FIG 1 .
Map of the sampling locations, indicated with blue arrows. WWTP, wastewater treatment plant. Data in the left panel were taken from Google Maps (Map data ©Google 2017).
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.