Protocol in Use:
1997-01-01 - current
Data Manager, Global Institute of Sustainability, Arizona State University,
Laboratory Sample Preparation and Analyses
Sample splitting and filtration
Set up the Dekaport cone splitter on a bench top; check it with the level bubble (a level splitter is critical to performance). All Teflon tubes leading off the splitter should be approx. the same length.
Rinse the splitter with some of the appropriate rinse water, then place 10 x 500ml bottles under the outlet tubes and rinse once again, including the collection bottles.
Agitate the sample (for 10 to 15 seconds) to resuspend the sediments. Invert the bottle and rapidly pour into the cone splitter reservoir. Maintain a head of water above the stand pipe to prevent air from entering the splitting block. If the sample consists of more than one bottle full of water, pour all additional bottles through the splitter before finishing. This way the sample is both composited and split into equal components.
The splitting procedure generates 10 equal sub-samples. These are processed as follows:
i) one unfiltered for laboratory specific conductivity (using meter)
ii) three filtered (using 47 mm diameter GF/F ashed at 500 o C) for total suspended solids TSS(gravimetric determination on 104 oC air-dried filter)
total dissolved solids TDS (using pan evaporation method)
total volatile solids TVS (using ashing of the remains from the pan evaporation)
DOC (40ml of filtrate are placed glass vials and analyzed within 24 hours on the Shimadzu TOC 5000)
iii) three filtered (using 47 mm diameter Supor membrane disc filters, filtrate collected in 125ml bottles and analyzed for anions:
TDN (25 ml for persulphate digestion and spectrophotometer)
TDP (25 ml for persulphate digestion and spectrophotometer)
nitrate, phosphate, chloride, (10 mls each for TRAACS) plus ammonium (non-preserved TRAACS method)
major ions e.g. sulphate, chloride (100 ml for IC)
iv) three filtered (using 47 mm diameter Supor membrane disc filters, filtrate collected in 125 ml bottles and analyzed for cations and metals:-
major cations (Ca, Mg, Na, K) analyzed using FAA
metals (Cu, Pb, Zn) remaining filtrate is transferred to nitric acid washed 125 ml bottles and stored in the cold room for eventual analysis by ICP-MS.
Samples should be measured at lab temperature. On returning to the lab take the sample syringes out of the cooler and allow them to warm up to room temp.
Then follow the procedure outlined on the attached sheet.
General Lab. Procedures
A. General Glassware Washing (Stream Lab. protocol).
1. All water chemistry glassware is to be washed with 10% HCL on the same day that it is used. Wear protective clothing.
a) REMOVE ALL REP. NUMBERS WITH ACETONE PRIOR TO WASHING (this does not include labels specifically marked NH4-N, NO3-N, or SRP).
b) Wet all surfaces with acid--check for any residue, scrub if necessary with test tube scrubber.
c) Rinse in bin filled with DISTILLED WATER (keep a constant flow of distilled water into bin).
d) Rinse under stream of distilled water 4X.
e) Drip dry in "clean acid washed glassware" cart--only small objects should be dried on Kimwipes.
f) Return glassware to acid wash cabinet in LSC026.
2. If same day acid washing is impossible, rinse all glassware and fill all vessels with distilled water. Place all glassware to be washed in acid wash room.
3. All glassware is to be washed (rinsed and scrubbed if necessary) in DISTILLED WATER ONLY. NO SOAP EVER!!
4. All pipets and burets should be submerged in 10% HCL in pipet canister, then rinsed with distilled water in the pipet washer 6X.