Protocols

Protocol for the Collection of Total Phosphorus (TP) and Total Nitrogen (TN) Samples

Materials needed:

1. Concentrated sulfuric acid (H2SO4, ~18M)
   
   1. Stored in glass scintillation vial (20 ml)
   2. Scintillation vial stored in 500 ml wide mouth Nalgene filled with pure baking soda (NaHCO3) – not available from grocery stores.
2. Glass or plastic Pasteur pipettes (one for each sample).
3. PPE: protective eye wear (sunglasses okay and gloves (nitrile)

Methods:

The following methods follow the BLM’s Lotic AIM National Aquatic Monitoring Framework: Field Protocol for Wadeable Lotic Systems, TR1735-2.

1. Obtain a pair of new nitrile gloves, and place them on both hands, being careful not to contaminate the outside of the gloves with substances such as sunscreen. 
2. Use a new 125 ml HDPE Nalgene bottles or one that has been acid washed in 10% HCl.  Rinse bottle and top five times with stream water. Be careful not to disturb the stream bottom.
3. Fill the bottle halfway with stream water directly from the stream.
4. Stabilize the sample using concentrate sulfuric acid solution.
5. Ensure that one always follows proper safety precautions when handling the H2SO4.  
6. Immediately following collection, sample is stabilized in the following way:
   
   1. Remove new Pasteur pipette from its storage container.
   2. Draw a small amount of concentrated sulfuric acid into dropper.
   3. Add 3 drops (0.15 ml) to the ~60 ml water quality sample, but do not touch the pipette to the water. If pipette touches water sample, discard sample and start from Step 2 again using same sample vial. 
   4. Firmly replace water quality bottle top and shake vigorously for 5 seconds.
7. Dip used end of pipette into baking soda and place in discard bin.
8. Safely close acid vial and baking soda storage container.
9. Clearly label sample using brightly colored tape with “Acid Stabilized” written on it.  In addition, include all other labeling per 1735-2.2 (section 5.2).
10. Although storage temperature of acid stabilized samples does not alter the TN/TP final values, once back in office environment, sample can be stored in freezer.

Protocol for the Collection of Specific Conductance

Materials needed:

Water quality sondes used to obtain in-situ water quality measurements must meet the following requirements: Specific conductance: accuracy of ±2 μS/cm or ±10% of the measured value, whichever is greater, and resolution of 0.1 μS/cm 

Methods:

The following methods follow the BLM’s Lotic AIM National Aquatic Monitoring Framework: Field Protocol for Wadeable Lotic Systems, TR1735-2.

1. Data collectors should maintain a calibration log documenting when and how water quality sondes were calibrated.
2. Review the calibration log to ensure the sonde was calibrated for specific conductance following manufacturer recommendations or within the last 7 days, whichever is shorter.
3. Record the most current calibration date.
4. If the sonde has not been calibrated in the last 7 days or within the manufacturer’s recommended timeframe, the sonde will need to be calibrated following the manufacturer’s directions. Prior to calibration, ensure that calibration standards are not expired.
5. Standing in the thalweg at in the middle of the reach and in flowing water, if present, lower the probe to a depth of 0.5 m below the water surface, taking care to avoid contacting the stream bottom. If water depth is < 1 m, take measurements at mid-depth.
6. Wait for the readings on the screen to stabilize (this could take up to a few minutes).
7. Record specific conductance (μS, not mS). 
8. Ensure the sonde is set to take measurements in the appropriate units and that temperature-corrected conductivity (i.e., specific conductance) is being measured. It is not acceptable to take these measurements later from a grab sample.
9. Record the model number and serial number of the instrument used so that any issues with the device can be tracked.
10. Note any odd water smells, surface films, or water discoloration observed during sampling.