Acid Deposition Sampling and Analysis
The following are summaries of the collection and analysis protocols. The complete protocols are detailed in the Quality Assurance Manual of the NYS Acid Deposition Network.
All sampling sites are serviced by the Division of Air Resources. Each site is visited weekly. The operator services the equipment and checks the hyetometer wet-side bucket for precipitation. The target period for this visit is Tuesday between 8 a.m. and 10 a.m.
The bucket installed in the wet-side of the hyetometer is lined with a polyethylene sample bag secured with an elastic cord. During the site visit, the operator activates the roof movement with a small quantity of distilled water to uncover the wet-side bucket.
The operator checks the lined bucket for the presence of precipitation. If enough sample has been collected, the operator removes and seals the old bucket and installs a new lined bucket. Samples are collected only when the operator determines there is enough sample for analysis (about 250 ml). The operator notes any problems or unusual events on the check sheet and in the site log.
The sample is transported into the field station and transferred from the collection bag to a 500 ml amber high density polyethylene bottle. Samples are immediately shipped to the State's laboratory in Albany and stored in a refrigerator until the analysis is performed.
Each precipitation sample is analyzed for conductivity, pH, and anion/cation concentration.
The anion and cation analyses are performed using a Dionex Ion Chromatograph.
The following anions and cations are measured and reported in units of ionic parts per million (ippm) using this method:
HPO4-- hydrogen phosphate