Analytical Methods as of 2004

ION

INSTRUMENT

TECHNIQUE

NH4+, PO4-3

NO3- (WC)

Alpkem Flow Solution III or Lachat QuikChem 8000 FIA

Phenate method (NH4+)1

Phosphomolybdate method (PO4-3)1

SO4-2, Cl-

NO3- (PPT, AQS)

Dionex 500 DX  Ion Chromatograph

Ion exchange chromatography, AS4A and AG4A columns, micro-membrane supressor2

K+, Na+

Perkin-Elmer Aanalyst 300 Atomic Absorption Spectrometer

Flame atomization, direct air3

Ca+2, Mg+2, SiO2

Leeman Labs Profile ICP

Emission spectroscopy

pH

Fisher-Accumet AR20 pH/conductivity meter with Thomas glass electrode, Fisher reference probe (precip. & stream) with Fisher Accu=pHast combination probe (AQ)

Standardization with Fisher 7.00 and 3.00 (precip.), 4.00 (AQ), 10.00 (stream) buffers; samples and buffers at room temperature

Specific Conductivity

Fisher-Accumet AR20 pH/conductivity meter

Direct reading

DOC (Dissolved Organic Carbon)

Shimadzu TOC 5050

High temperature combustion of sample; platinum catalyst C to CO2, NDIR detect.

 1 #00578 Standard Alpkem Methods (NH4+) #00580 (PO4-3), Alpkem Corp, Clakamas OR QuikChem method #10-107-065-1-J (NH4+), #10-115-01-1-M (PO4-3), 2000, Lachat Instruments, Milwaukee, WI 

2 Small, H., Stevens, T.S. and Bauman, W.C.  1975.  Anal. Chem. 47:1801-1809.

3 Slavin, W.  Atomic absorption spectroscopy.  1968.  Wiley-Interscience, New York.

WC=Wappinger Creek Stream Samples

PPT=Precipitation Samples

AQS=Low-Volume Filter Pack Samples