Chemical monitoring is a very important aspect of being a Blue Thumb Monitoring Volunteer, since it can offer a snapshot look into what their creek is doing. Once a month, these volunteers perform chemical tests on their stream site. This involves completing a data sheet about the creek at that point in time, as well as obtaining creek water to perform these tests. Our volunteers measure dissolved oxygen (DO), pH, ammonia nitrogen, nitrates and nitrites, chloride, orthophosphate phosphorus, temperature, and water clarity (using a secchi disk). These results are recorded on a Blue Thumb data sheet and emailed to Blue Thumb headquarters, where they are entered into a database for upload into the Environmental Protection Agency's STORET program.