STANDARD OPERATING PROCEDURE
Collection of Lake Specific Samples
and Field Parameters
Mecklenburg CountyLand Use and Environmental Services Agency
Water Quality Program
David Buetow / Sr. Environmental Specialist / Project Officer
Jeff Price / Environmental Analyst / QA/QC Officer
Rusty Rozzelle / Water Quality Program Manager
City of Charlotte
Engineering and Property Management
Storm Water Services
Steve Jadlocki / Sr. Water Quality Specialist
Daryl Hammock / Water Quality Program Manager
Charlotte-Mecklenburg Storm Water Services
Charlotte, NC
Lake Sampling SOP; Rev. 1.2
Effective Date: 1/1/09
Page: 11 of 11
ftp://ftp1.co.mecklenburg.nc.us/WaterQuality/Policies%20and%20Procedures/QAPP/
Standard Operating Procedure
Modification / Review Log
Version / Eff. Date / Author / Summary of Changes / Approved / Date1.0 / 1/23/07 / David Buetow / Original Draft / Jeff Price / 2/26/07
1.1 / 3/2/07 / David Buetow / Formatting changes – minor / Jeff Price / 3/2/07
1.2 / 1/1/09 / Jeff Price / Field Validation, minor formatting changes / Jeff Price / 1/1/09
1.3 / 4/8/09 / David Buetow / Minor formatting changes / Jeff Price / 4/8/09
Lake Sampling SOP; Rev. 1.2
Effective Date: 1/1/09
Page: 11 of 11
ftp://ftp1.co.mecklenburg.nc.us/WaterQuality/Policies%20and%20Procedures/QAPP/
1.0 Scope and Applicability
1.1 This SOP is applicable to the sample collection of representative water at varying depths in lakes, ponds and reservoirs for the analysis of chemical and physical parameters using samplers.
2.0 Summary of Method
2.1 Lake water samples are collected using either a Labline composite sampler or Van Dorn discrete sampler depending on application and dispensed into certified clean, pre-preserved bottles suitable for relevant laboratory analysis. All samples are submitted to a NC State certified laboratory for the analysis and quantification of lake water pollutants.
3.0 Health and Safety Warnings
3.1 Always wear gloves when sampling to protect you from possible contaminants in the water and also the potential spillage of acid preservatives from sample bottles. Decontaminate hands using a no-rinse hand sanitizer.
3.2 Sampling activities conducted from a boat pose additional risks related to boating accidents, hypothermia and drowning. Always obey all boating safety regulations and wear Personal Floatation Devices on-board at all times. When the water temperature is below 15 C, field staff should wear Personal Floatation Devices that also provide protection from cold water such as float coats or one piece hypothermia suits. See Boat Operations and Safety Guidelines for further information.
4.0 Interferences
4.1 Thoroughly rinse the Labline or Van Dorn water bottle between sites to avoid contamination with water from a previous site. Unclean equipment will definitely interfere with the quality of the sample collected.
4.2 Disturbing the bottom at shallow sites is a potential interference. Make sure that the sampler does not stir up bottom sediments as it is lowered into the water column as they might be picked up in the sampler. If it appears this might be the case discard the sample, move the boat and collect another sample.
4.3 Avoid hard hits with the boat on buoys at the forebay locations where buoys are used to tie up to at the sampling site. Hard hits on the buoys may dislodge attached material on the outside of the buoys that may be picked up in the samples.
4.4 Take care not to overfill sample bottles especially those that have preservatives already added. Too much sample in a pre-preserved container can dilute the effectiveness of the preservative.
4.5 Avoid any contact with the sample or with the sample container as that can potentially contaminate the sample. Protective gloves are used to protect the sampler and the gloves themselves are not certified clean or sterile.
4.6 Cross-contamination of samples during transport is also a potential interference. Always place filled samples collection bottles (samples) upright in the cooler so that the neck and cap are above the level of the ice. Drain ice melt-water from coolers periodically to ensure that sample bottles are not submerged.
5.0 Equipment and Supplies
5.1 The following equipment is generally needed for Sample Collection of representative lake water:
· CMU Lab Chain of Custody Form (Attachment 1)
· Certified clean, pre-preserved sample collection bottles appropriate for intended parameter analysis (provided by CMU)
· Sample bottle self-adhesive labels
· 4-liters of lab distilled/de-ionized reagent grade water in a certified clean plastic jug (8-liters or two jugs if both samplers used)
· Sterilized bacteriological buffer blank solution
· Labline sampler with marked rope
· Van Dorn sampler with marked rope (if necessary)
· Secchi disk with marked rope
· YSI 6600 Multiprobe with YSI 650 Hand held datalogger and 125’ cable
· pH standards for in field calibration checks
· Lake Log book
· Sharpie, pen
· GPS unit with sampling locations marked and/or Map Book
· Coolers with ice
· Gloves and hand sanitizer
6.0 Lake Sample Collection – Preparation
6.1 Notify the CMU Laboratory of the date of the sampling run and provide them with the number of sites and parameters for analysis.
6.2 Print the appropriate Chain of Custody (COC) forms required for the sampling event.
6.3 Edit bottle label forms for lake runs with all known information for the sampling run (Staff Initials, Date, Parameters, and Preservative). Leave the Sample Collection Time blank on the label as this will be completed at the site by hand at the time of collection.
6.4 Preprint the self-adhesive bottle labels using the Bottle Label Printer.
6.5 Assemble required sample collection bottles for each site to be sampled and put the preprinted labels on the appropriate bottle.
6.6 Include extra bottles in case of accidents, defective bottles or in case environmental conditions on the run warrant the collection of additional samples.
6.7 When required by a project or program element, assemble additional set(s) of sample collection bottles for QC blanks.
6.8 If QC blanks are required, secure sterilized bacteriological buffer blank solution from the CMU lab, or distilled/de-ionized reagent grade water (for chemical/physical parameters) for each blank sample set from the Hal Marshall Lab.
6.9 Calibrate the YSI 6600 multiprobe utilizing the YSI SOP.
6.10 Fill coolers (as many as needed) approximately ¼ full of ice.
7.0 YSI Multiprobe Depth Profiles (Lake Field Parameters)
7.1 At the first lake site set up the YSI 6600 as follows.
7.1.1 Fill the bucket about 2/3 full of lake water.
7.1.2 Remove the plastic calibration cup covering the probes on the YSI and replace with the slotted probe guard with attached weight.
7.1.3 Submerge the YSI sensors in the lake water in the bucket.
7.2 Turn on the YSI and press the Enter key at the 650 Main Menu to enter Sonde run mode. (This will establish the connection between the YSI 650 and the Sonde.) Allow the unit to warm up for several minutes.
7.3 When ready, lower the YSI multiprobe over the side of the boat into the lake near the surface (0.2 m). (Note: depth is read directly off the 650 screen from the depth sensor on the sonde.)
7.4 Wait for the unit to stabilize and for the two wiped optical sensors to finish wiping the sensors before taking any readings.
7.5 After the unit has stabilized, store the YSI reading in the 650 data logger.
7.5.1 While in Sonde Run mode first hit the Enter key when “Log One Sample” is highlighted on the left side of the screen under 650. (Note: Data may also be stored to the sonde if the memory in the 650 is full.)
7.5.2 Scroll through the site list and highlight the correct site name that is being sampled. (Note: The 650 unit will return to the previously highlighted site name.)
7.5.3 Press the Enter key to store the data.
7.5.4 Press the Escape key on the keypad to return to the Sonde run screen where the data is displayed.
7.6 Record the surface (0.2 m) YSI readings in the lake log book in ink. (See Example in Attachment 3).
7.7 Lower the sonde at 1 meter intervals (1.0, 2.0, 3.0, 4.0, etc.) and repeat Step 7.5 to record the data at each depth.
Note: For deeper sites during midwinter runs (December, January or February), increase depth by 5m increments below 10m.
7.8 Discontinue recording field measurements when the sonde touches the bottom of the lake. Pull the YSI 6600 sonde back up to the surface, coiling the cable in the transport bin.
7.9 Immerse the YSI multiprobe in the bucket of lake water when not being used to take field measurements. Leave unit powered on between sites.
8.0 pH Field Check
8.1 At least once during the run, check the pH probe calibration using the pH 7.0 standard.
8.2 Remove the probe guard and rinse the sensors and calibration cup with distilled/de-ionized water.
8.3 Pour pH 7.0 Rinse Standard into the Calibration Cup and immerse the sensors.
8.4 Pour the pH 7.0 Rinse Standard back into the stock bottle and pour pH 7.0 Standard into the Calibration Cup.
8.5 Let the unit stabilize for about one minute and take a reading.
8.6 If the unit reads +/- 0.1 units from 7.0 note this in the lake log.
8.7 If the unit reads more than 0.1 unit from the pH 7.0 Standard recalibrate using the pH 7.0, pH 4.0 and pH 10.0 standards. (Note: Doing a two point calibration to pH 7.0 and pH 10.0 standards is also acceptable for lakes.)
9.0 Secchi Depth (Lake Field Parameter)
9.1 Avoiding any shadows from the boat lower the Secchi disk into the water until you can no longer see it. Using the attached measured rope, slowly pull the Secchi disk up and down several times to confirm the depth where the disk is no longer visible.
9.2 Read the depth where the disk disappears from the measured rope to the nearest tenth of a meter (e.g., 2.2 m).
9.3 Record the Secchi depth in the lake field log book.
10.0 QC Bacteriological Blank Collection
10.1 At the first site of each run, label the blank bottles with the approximate Sample Collection Time (+/- 5 minutes).
10.2 Remove the cap from the sterilized buffered bacteriological blank solution as appropriate.
10.3 Remove the blank collection bottle cap(s).
10.4 Place the blank collection bottle(s) on level, stable surface. Fill the blank collection bottle(s) to the indicated mark with the buffered blank solution.
10.5 Replace the sample collection bottle cap(s) and place the sample bottles in coolers on ice.
11.0 QC Equipment Blank Collection (Labline / Van Dorn)
11.1 At the first site of each run, label the blank bottles with the approximate Sample Collection Time (+/- 5 minutes).
11.2 Remove the cap from the distilled/de-ionized reagent grade water.
11.3 Rinse the Labline and/or Van Dorn Sampler with the distilled/ de-ionized water.
11.4 Pour enough distilled/de-ionized water into the Labline and/or Van Dorn Sampler for required analyses.
11.5 Dispense the water in the Labline and/or Van Dorn Sampler into the blank sample bottles and fill the bottles as in Step 10.4.
11.6 Replace the sample collection bottle caps and place the sample bottles in coolers on ice.
12.0 Sample Collection (Lake Depth Composite and Discrete Samples)
12.0 Label the sample collection bottles with the approximate Sample Collection Time (+/- 5 minutes) using an indelible ink pen.
12.1 Lake specific samples are collected as a euphotic zone composite and/or as a discrete sample typically collected just off the bottom.
12.1.1 Collect the Euphotic Zone composite sample by using the LabLine sampler. (Note: The Euphotic Zone is the approximate depth of light penetration where algae can grow in the reservoir. It is defined as twice the Secchi Depth.)
12.1.1.1 Make sure both plugs are removed from the top of the Labline sampler.
12.1.1.2 Rinse the Labline sampler several times with lake water at the site to be sampled.
12.1.1.3 Quickly lower the sampler to twice the Secchi depth and slowly pull to the surface. Pull the sampler at a steady speed so as to fill it just as it hits the surface. If the sampler has not completely filled at the surface repeat lowering and raising the Labline sampler within the euphotic zone until it is full. If the sampler clearly fills up completely before it hits the surface (bubbles stop coming out the top of the sampler), dump the sample and start again.
12.1.1.4 Pour the contents of the Labline sampler into the appropriate sample bottles.
12.1.2 Collect discrete bottom samples using the Van Dorn sampler.
Note: Discrete bottom samples are generally only collected during the summer months when the lake is stratified, or as directed by the Project Officer.
12.1.2.1 Pull the two ends with the elastic connector out from the sampler and hook the metal loops attached to the ends onto the pins sticking up from the tripping mechanism in the center of the sampler.
12.1.2.2 Lower the Van Dorn Sampler to the desired depth, usually about 1 or 2 meters above the bottom. (Note: Be careful not to disturb the bottom in any way.)
12.1.2.3 Rotate the top of the metal messenger to open the groove to fit on the rope.
12.1.2.4 Slide the metal messenger onto the rope, lock in place and drop the messenger.
12.1.2.5 After you feel the messenger engage the tripping mechanism on the sampler pull the sampler and sample to the surface.
12.1.2.6 Pour the contents of the Van Dorn sampler into the appropriate sample bottles.
12.1.3 Place all collected samples on ice in the coolers.
13.0 Post-Sample Collection
13.1 Periodically check the ice in the coolers for melting. Drain excess melt water out of the coolers to prevent sample bottles from becoming submerged if necessary.
13.2 Complete the COC per the COC Procedure.
13.3 Deliver all sample bottles in the cooler on ice to the CMU Lab for analysis.
14.0 References
14.1 YSI Environmental Monitoring Systems 6 – Series Operating Manual
14.2 YSI Multiprobe Calibration and Field Data Collection (Short-Term Deployment) SOP
15.0 Attachments
15.1 CMU Chain of Custody Form (Example)
Lake Sampling SOP; Rev. 1.2
Effective Date: 1/1/09
Page: 11 of 11
ftp://ftp1.co.mecklenburg.nc.us/WaterQuality/Policies%20and%20Procedures/QAPP/