# **ADP Bucket Inspection/Rinsing, Bagging and New Bucket Prep**
Updated July 2020
### **Inspection:**
* Wipe any moisture, dirt, or debris off the outside of all buckets and lids with a dry paper towel.
* Inspect buckets/lids for cracks, chips, stains, and rust on the bucket handle. If the weight appears to have changed by these means but the buckets/lids are still good, be sure to reweigh the buckets/lids with the 12kg balance in GWC 681, relabel with a Sharpie, and circle any defects. The buckets also change weight over time due to outdoor exposure. It is useful to reweigh any used buckets every few months to make sure the weights are accurate; relabel with a Sharpie if necessary.
* Check that the ID and weights are still visible and legible. If necessary, rewrite with a Sharpie.
### **Rinsing:**
* Put on a pair of nitrile gloves and thoroughly rinse them with nanopure water.
* Rinse the exterior of the bucket/lid with nanopure water to loosen any contamination. Use a small scrub brush if necessary.
* Rinse the interior of the bucket/underside of the lid with nanopure water.
* Rinse a natural sponge thoroughly with nanopure water then wipe the interior surface. Use a small scrub brush if necessary.
* Rinse the bucket interior surface with nanopure water four times, 1/4 turn between each rinse.
* Set the bucket upside down on the drying cart or on paper towels on the counter. Place the lid similarly on the drying cart/paper towels with the underside facing downward.
* Buckets/lids will dry within 24hr if air is allowed to circulate inside (e.g., by leaning on a neighboring bucket/lid or overhanging a counter's edge a bit).
### **Bagging:**
* Using 13gal garbage bags for buckets and 4gal garbage bags for lids, place the buckets/lids into new plastic garbage bags by using the outside of the bags as gloves.
* Buckets should have the open end towards the bottom of the bag.
* Squeeze the air out of the bag and close with a twist tie.
### **New bucket prep:**
* Clean new buckets/lids as described above under "Rinsing".
* Fill the bucket with distilled water. While filling, add 1mL of 0.6N HNO<sub>3</sub> solution (38.2mL concentrated HNO<sub>3</sub>/L) using a rinsed pipet tip. Fill the bucket to 2cm below the rim.
* Place a clean lid on top of the bucket and set aside for 7 days to leach.
* After 7 days, clean the bucket/lid again as described under "Rinsing".
* Weigh the bucket/lid with the 12kg balance in GWC 681, recording the ID and weight with a Sharpie twice on the side and once on the bottom of the bucket/twice on the side and once on the top of the lid.
# **ADP Bulk Deposition Funnel Collector**
Updated July 2020
Bulk deposition samples are collected along with ADP wet buckets. If there has been no precipitation during the month, then the funnel and sample bottle should be inspected for damage and, if necessary, replaced with clean ones when the ADP dry bucket is collected. During periods of heavy rainfall, the sample bottle should be collected before it overflows.
Funnels are acid washed with 10% HCl prior to installation. Sample collection bottles are 1gal bottles that have been acid washed with 10% HCl. Once clean and dry, weigh the sample bottle with its cap on on the 12kg balance in GWC 681. Write its weight and ID on the side of the bottle with a Sharpie. The collected sample is routed through looped Tygon tubing between the funnel and bottle and forms a vapor trap to prevent evaporation of the sample. Tygon tubing running from the sample bottle to a 4oz bottle containing nanopure water provides a second vapor trap but allows the sample bottle to breathe during precipitation collection.
In order to prevent bird droppings or insects from entering the funnel and contaminating the sample, a 17in x 17in piece of 10% HCl-washed fiberglass screen is tied to the top of the funnel using thin wire. Additionally, a small 2cm square of 10% HCl-washed blue aquarium filter is placed in the bottom of the funnel on top of the stopper.
Clean funnels are placed in 13gal garbage bags and stored with ADP buckets. Clean 1gal sample bottles are stored in the same area. Other supplies (thin wire, 4oz bottles, Tygon tubing, stoppers, cable ties, Velcro, nanopure water rinse bottle, spare quick connects, screens, and aquarium filters) are stored in a sweater box in the cabinet where the ADP backpack is kept in GWC 639.
The bulk deposition funnel collector is located on the roof of LSA. Access is via a locked gate. The key to the roof lock is kept in the desk drawer in GWC 681 and is labeled "LSA Roof" with white lab tape.
### **Sample collection:**
Inspect funnel for contamination (e.g., bird droppings, insects). If present, continue with the sample collection and funnel/bottle replacement procedures, but discard the contaminated sample. Do not prepare it for analysis.
Replace the screen-covered funnel with a clean one that has been acid washed. Wear nitrile gloves when handling replacement funnels to minimize Na contamination. Also, replace the aquarium filter and rubber stopper in the neck of the funnel with ones that have been acid washed.
Disconnect the tubing from the funnel at the quick connect (on the 1gal bottle cap) and pour about 250mL of nanopure water into the funnel to rinse the tubing. Reconnect the tubing when finished.
Unscrew the cap of the replacement 1gal bottle; put the cap from this bottle on the sample bottle. Put the new bottle on the stand and replace the cap. The easiest way to do this is to screw the bottle onto the cap, making sure the seal is tight. Record the sample bottle number and weight on the ADP field datasheet under "Buckets" under site "Fun". The "Lid" portion of the field sheet will not be used. Note any contaminants on the funnel (e.g. bird droppings, insects) under "Contaminants" on the field sheet. Remember to discard contaminated samples.
Inspect the 4oz bottle and replace with a new one half-filled with nanopure water if necessary. Reuse the holed cap. Make sure the Tygon tubing extends down into the water.
When replacing tubing, bring one 18in-long piece to connect from the funnel to the 1gal bottle and another 23in-long piece to connect from the 1gal bottle to the 4oz bottle. Make sure the tubing that connects the funnel and the 1gal bottle is looped to form a vapor trap. Secure both pieces of tubing to the PVC frame.
Weigh the capped 1gal sample bottle on the 12kg balance in GWC 681 and record the weight on the ADP field datasheet.
Samples should be refrigerated if not processed right away.
Process samples the same as an ADP wet bucket sample.
### **Maintenance:**
Funnels and bottles may become brittle and crack due to repeated acid washings and outdoor exposure. They should be discarded and replaced with new ones.
Tygon tubing will become yellowed and start to break down from outdoor exposure. Dirt may accumulate along the walls of the tubing and algae may also start to grow and discolor the tubing. Replace the tubing at the first sign of any of the above.
### **Ordering information:**
* 311mm diameter LDPE funnels: Fisher #10-349B
* One-hole No. 1 rubber stoppers: Fisher #14-135C
* Tygon tubing 3/16in inside diameter x 1/16in wall thickness: Fisher #15-315-6a
* 1gal bottle: Fisher #02-911-992
* 4oz bottle: Fisher #02-911-958
* 18-24in bonded blue and white pre-filter (coarse): Pure-flo
* Roll of grey fiberglass screen: Home Depot
# **ADP Sample Collection Protocol**
Updated July 2020
### **Supplies:**
* Buckets (weighed, bagged, and labeled)
* Lids (weighed, bagged, and labeled)
* Backpack with ADP field datasheets and instructions, cleaning cloths/sponges, sandpaper, wire brush and/or water bottle, screwdriver, mineral oil, and Vaseline
### **Field Procedure/Sampling Schedule:**
Dry buckets are changed monthly, all on the same day (the third Tuesday of each month).
Wet buckets are collected/changed according to the following rules:
* Collect a sample after EVERY rainfall event.
* If a series of storms is expected over a period of days, wait until the storms are over to collect.
Once collected, the buckets should be prepped right away. If this is not possible, then the buckets may be placed in the cold room in GWC 675 to wait for prepping.
Be careful not to contaminate the old or new bucket. If the sample is spilled or the bucket is dropped at any time, especially if the rim of the bucket or lid contacts any surfaces, make a note.
### **Changing the wet side bucket:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, amount of rain in the rain gauge, lid label and weight, old bucket label and weight, new bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
While the roof is still covering the dry side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, if necessary, waiting until the roof moves back to the wet side.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing the dry side bucket:**
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, lid label, old bucket label, new bucket label, and contaminants.
Inspect the battery in its housing and check the voltage with a volt meter and record on the datasheet. The voltage should be above 13V. If not, it may be time to replace the battery with a new one.
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. See the troubleshooting section below if there is a problem.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Before replacing the dry bucket and with the roof covering the wet side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing both buckets:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record initials, time, date, amount of rain in rain gauge, lid label and weight, old wet bucket label and weight, new wet bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record the lid label, old dry bucket label, new dry bucket label, and contaminants.
Now that both buckets have been removed, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample buckets.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Again, short out the sensor with a few drops of water or wire brush, and then using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Place the securely closed buckets into the garbage bags the clean buckets were in.
If the sensor, motor, or battery is not working and the roof has stuck allowing water in the dry or both sides, pour all samples into the dry bucket, record on the field datasheet that this is a "bulk" sample (i.e., wet and dry composition combined), and then put the collector in "bulk" sample mode (wet bucket is exposed). If the collector motor box will not move the lid, reach under the main frame of the collector and push the clutch arm counter-clockwise. The clutch will disengage and the lid mechanism will be free of the drive system. Manually position the lid over the dry side bucket and use the bucket retaining springs to secure the lid. Disconnect the collector from the power supply.
### **Troubleshooting Tips for ADP Collector:**
If the collector fails to operate, try the following:
* Check the power source.
* Battery: Check for corrosion of the battery cable connections at the battery and at the motor. Many times the connectors at the battery become corroded, resulting in a bad connection. Sanding the connectors clean will solve this problem. Check the battery voltage; the battery may be dead. If the connectors at the motor are the problem, sand clean, apply Vaseline and reconnect.
* Check the wet sensor. Replace with a spare and see if the collector operates. If not, then the motor is bad and must be replaced. A faulty motor box is usually indicated by one of four things:
* Upon a "wet" sense, the roof cycles continuously back and forth.
* Upon a "dry" sense, the roof cycles continuously back and forth.
* The motor does not run at all, even when the crank arm is placed in a vertical position by hand.
* The temperature of the sensor plate is HOT when the collector is in the "dry" collection state.
All of these conditions indicate that one of the mercury wetted switches within the motor is faulty. Unfortunately, Aerochem Metrics, the company that manufactured the ADP collectors, no longer exists and collectors of this type are no longer made. The only remedy is to remove the motor, which comes off as a unit, and replace it with a spare. If no spares are available, then it may be necessary to purchase the new-type collector manufactured by N-CON Systems [here](http://www.n-con.com/Products/ads.html).# **ADP Sample Processing Protocol**
Updated July 2020
Upon returning from the field, remove the buckets from garbage bags and wipe any soil/debris off the top, bottom, and sides of each bucket. When necessary, buckets can be left in the cold room for up to a week before weighing.
## **Dry collection:**
Wearing nitrile gloves, open the dry bucket and remove any contamination (insects, bird droppings, etc.) with 10% HCl-washed and nanopure-rinsed forceps. Ensure contaminants are noted on the field datasheet.
Using a Nanopure-rinsed 500mL graduated cylinder, add 500mL of nanopure water to the bucket.
With the lid off, swirl the water around the inside of the bucket as high as possible without any risk of spillage. Rest the lid loosely on top of the bucket (do not push lid down).
Place the bucket on the reciprocal shaker in GWC 681 for 10 minutes.
Rinse a 500mL plastic 10% HCl-rinsed bottle with a small amount of sample (~5-10mL), then pour the remaining sample from the bucket into the bottle. Record the HCl bottle number on the field datasheet.
Replace the lid on the bucket and set aside to be cleaned.
### **For ammonium (NH<sub>4</sub><sup>+</sup>) and nitrate (NO<sub>3</sub><sup>-</sup>) analysis:**
Label an ammonium centrifuge tube with "ADP", "site-D" (for dry collection, "site-W" for wet collection), and date.
Rinse the tube with a small amount of sample and then fill and cap.
Centrifuge at 8000rpm for 10min (make sure rotor is balanced).
Place the tubes in a tube rack labeled with the date and "ADP-N", then store the tubes in the freezer in GWC 630 for analysis on the Lachat flow-injection analyzer.
### **For Dissolved Organic Carbon (DOC) analysis:**
Using a clean, Nanopure-rinsed 25mm filter apparatus with an ashed GF/F 25mm filter, filter a small amount of sample (~5mL) to rinse and then discard.
Label a 40 mL glass DOC vial with ‘ADP’, ‘site-D’ (for dry collection; ‘site-W’ for wet), and the date.
Filter ~50 ml of sample. Rinse the vial with filtered sample, then discard the rinse and fill the DOC vial with the remaining filtrate until almost full.
Rinse the filter apparatus with nanopure before beginning the next sample.
Acidify each sample with 2 drops of concentrated HCl.
Place the samples in a tube rack labeled with the date and "ADP DOC-Acidified" on a strip of tape, then store the vials in the cold room in GWC 675 until the samples can be run (preferably within 24hr).
### **For anion and cation analysis:**
Label two sterile 50mL centrifuge tubes with "ADP", "site-D" (for dry collection, "site-W" for wet), and "anions" or "cations" (one of each).
Using a clean, Nanopure-rinsed 47mm filter apparatus with a Supor-450 47mm membrane filter, filter a small amount of sample (~15mL) to rinse and then discard.
Filter enough of the remaining sample to rinse and fill the two 50mL centrifuge tubes.
Fill the anion tube with filtrate, then cap. The centrifuge tubes are sterile so do not need to be rinsed with sample prior to filling.
Repeat with the cation tube.
Rinse the filter apparatus with Nanopure before beginning the next sample.
Place the anion samples in a Styrofoam tube holder labeled with the date and "ADP Anions" on a strip of tape, then store the tubes in the cold room in the freezer in GWC669 until samples can be run (preferably within 24-48 hours of collection for reactive species).
Place the cation samples in a Styrofoam tube holder labeled with the date and "ADP Cations-Acidified" on a strip of tape and then acidify the cation samples as follows:
* Place an empty 50mL centrifuge tube on the balance and tare.
* Weigh the cation centrifuge tube on the tared balance and record the sample weight (in grams) on the datasheet.
* Multiply the weight by 20. The result equals the amount (in microliters) of trace metal grade nitric acid to add. Record this volume on the datasheet.
* Under the hood, use an adjustable pipette with a filtered pipette tip to add the acid to the samples.
* Once acidified, the samples are stored on the bench in the storage room in GWC 681.
## **Wet collection:**
Notes:
If there is less than ~10mL of sample in the wet bucket, note this on the datasheet and do not process the sample. If the sample bottle volume is limited (i.e., 10 < 140mL) or lost, note the unprocessed subsamples on the field datasheet.
In cases when there is not enough rain to complete all of the analyses, the sampling priority is as follows: ammonium/nitrate, DOC, anions, cations, pH. See the following table for volume requirements for each analysis:
Remove the wet collection bucket from the garbage bag and wipe any soil/debris off the top, bottom, and sides of each bucket.
Tare the 12kg balance in GWC 681 and weigh each bucket.
Record the total weight (in kg) on the field datasheet. Subtract the lid and bucket weights from the total weight and record the net sample weight (in g) on the field datasheet.
Perform the analyses described above for the dry collection protocol.
After the last step of the dry collection protocol, measure the pH of the sample remaining in the 500mL 10% HCl-rinsed bottle using the pH meter in GWC 677 and record on the datasheet.
## **Lab cleanup:**
Rinse, dry, and 10% HCl-wash any glassware used.
Clean buckets and lids according to the "ADP Bucket/Lid Inspection/Rinsing, Bagging, and New Bucket Prep" protocol.
Ensure an adequate supply of ashed 25mm GF/F filters (4hr in muffle furnace at 500°C).
Filters can be removed from the furnace the following day.
Note: Bulk Samples - If dry buckets have collected rainwater due to a collector malfunction, process this water as a bulk sample (see ADP Sample Collection Protocol). Add the water from the wet bucket to the dry bucket, then weigh and process as a wet bucket EXCEPT swirl the sample as you would a dry bucket before proceeding.
# **ADP Bucket Inspection/Rinsing, Bagging and New Bucket Prep**
Updated July 2020
### **Inspection:**
* Wipe any moisture, dirt, or debris off the outside of all buckets and lids with a dry paper towel.
* Inspect buckets/lids for cracks, chips, stains, and rust on the bucket handle. If the weight appears to have changed by these means but the buckets/lids are still good, be sure to reweigh the buckets/lids with the 12kg balance in GWC 681, relabel with a Sharpie, and circle any defects. The buckets also change weight over time due to outdoor exposure. It is useful to reweigh any used buckets every few months to make sure the weights are accurate; relabel with a Sharpie if necessary.
* Check that the ID and weights are still visible and legible. If necessary, rewrite with a Sharpie.
### **Rinsing:**
* Put on a pair of nitrile gloves and thoroughly rinse them with nanopure water.
* Rinse the exterior of the bucket/lid with nanopure water to loosen any contamination. Use a small scrub brush if necessary.
* Rinse the interior of the bucket/underside of the lid with nanopure water.
* Rinse a natural sponge thoroughly with nanopure water then wipe the interior surface. Use a small scrub brush if necessary.
* Rinse the bucket interior surface with nanopure water four times, 1/4 turn between each rinse.
* Set the bucket upside down on the drying cart or on paper towels on the counter. Place the lid similarly on the drying cart/paper towels with the underside facing downward.
* Buckets/lids will dry within 24hr if air is allowed to circulate inside (e.g., by leaning on a neighboring bucket/lid or overhanging a counter's edge a bit).
### **Bagging:**
* Using 13gal garbage bags for buckets and 4gal garbage bags for lids, place the buckets/lids into new plastic garbage bags by using the outside of the bags as gloves.
* Buckets should have the open end towards the bottom of the bag.
* Squeeze the air out of the bag and close with a twist tie.
### **New bucket prep:**
* Clean new buckets/lids as described above under "Rinsing".
* Fill the bucket with distilled water. While filling, add 1mL of 0.6N HNO<sub>3</sub> solution (38.2mL concentrated HNO<sub>3</sub>/L) using a rinsed pipet tip. Fill the bucket to 2cm below the rim.
* Place a clean lid on top of the bucket and set aside for 7 days to leach.
* After 7 days, clean the bucket/lid again as described under "Rinsing".
* Weigh the bucket/lid with the 12kg balance in GWC 681, recording the ID and weight with a Sharpie twice on the side and once on the bottom of the bucket/twice on the side and once on the top of the lid.
# **ADP Bulk Deposition Funnel Collector**
Updated July 2020
Bulk deposition samples are collected along with ADP wet buckets. If there has been no precipitation during the month, then the funnel and sample bottle should be inspected for damage and, if necessary, replaced with clean ones when the ADP dry bucket is collected. During periods of heavy rainfall, the sample bottle should be collected before it overflows.
Funnels are acid washed with 10% HCl prior to installation. Sample collection bottles are 1gal bottles that have been acid washed with 10% HCl. Once clean and dry, weigh the sample bottle with its cap on on the 12kg balance in GWC 681. Write its weight and ID on the side of the bottle with a Sharpie. The collected sample is routed through looped Tygon tubing between the funnel and bottle and forms a vapor trap to prevent evaporation of the sample. Tygon tubing running from the sample bottle to a 4oz bottle containing nanopure water provides a second vapor trap but allows the sample bottle to breathe during precipitation collection.
In order to prevent bird droppings or insects from entering the funnel and contaminating the sample, a 17in x 17in piece of 10% HCl-washed fiberglass screen is tied to the top of the funnel using thin wire. Additionally, a small 2cm square of 10% HCl-washed blue aquarium filter is placed in the bottom of the funnel on top of the stopper.
Clean funnels are placed in 13gal garbage bags and stored with ADP buckets. Clean 1gal sample bottles are stored in the same area. Other supplies (thin wire, 4oz bottles, Tygon tubing, stoppers, cable ties, Velcro, nanopure water rinse bottle, spare quick connects, screens, and aquarium filters) are stored in a sweater box in the cabinet where the ADP backpack is kept in GWC 639.
The bulk deposition funnel collector is located on the roof of LSA. Access is via a locked gate. The key to the roof lock is kept in the desk drawer in GWC 681 and is labeled "LSA Roof" with white lab tape.
### **Sample collection:**
Inspect funnel for contamination (e.g., bird droppings, insects). If present, continue with the sample collection and funnel/bottle replacement procedures, but discard the contaminated sample. Do not prepare it for analysis.
Replace the screen-covered funnel with a clean one that has been acid washed. Wear nitrile gloves when handling replacement funnels to minimize Na contamination. Also, replace the aquarium filter and rubber stopper in the neck of the funnel with ones that have been acid washed.
Disconnect the tubing from the funnel at the quick connect (on the 1gal bottle cap) and pour about 250mL of nanopure water into the funnel to rinse the tubing. Reconnect the tubing when finished.
Unscrew the cap of the replacement 1gal bottle; put the cap from this bottle on the sample bottle. Put the new bottle on the stand and replace the cap. The easiest way to do this is to screw the bottle onto the cap, making sure the seal is tight. Record the sample bottle number and weight on the ADP field datasheet under "Buckets" under site "Fun". The "Lid" portion of the field sheet will not be used. Note any contaminants on the funnel (e.g. bird droppings, insects) under "Contaminants" on the field sheet. Remember to discard contaminated samples.
Inspect the 4oz bottle and replace with a new one half-filled with nanopure water if necessary. Reuse the holed cap. Make sure the Tygon tubing extends down into the water.
When replacing tubing, bring one 18in-long piece to connect from the funnel to the 1gal bottle and another 23in-long piece to connect from the 1gal bottle to the 4oz bottle. Make sure the tubing that connects the funnel and the 1gal bottle is looped to form a vapor trap. Secure both pieces of tubing to the PVC frame.
Weigh the capped 1gal sample bottle on the 12kg balance in GWC 681 and record the weight on the ADP field datasheet.
Samples should be refrigerated if not processed right away.
Process samples the same as an ADP wet bucket sample.
### **Maintenance:**
Funnels and bottles may become brittle and crack due to repeated acid washings and outdoor exposure. They should be discarded and replaced with new ones.
Tygon tubing will become yellowed and start to break down from outdoor exposure. Dirt may accumulate along the walls of the tubing and algae may also start to grow and discolor the tubing. Replace the tubing at the first sign of any of the above.
### **Ordering information:**
* 311mm diameter LDPE funnels: Fisher #10-349B
* One-hole No. 1 rubber stoppers: Fisher #14-135C
* Tygon tubing 3/16in inside diameter x 1/16in wall thickness: Fisher #15-315-6a
* 1gal bottle: Fisher #02-911-992
* 4oz bottle: Fisher #02-911-958
* 18-24in bonded blue and white pre-filter (coarse): Pure-flo
* Roll of grey fiberglass screen: Home Depot
# **ADP Sample Collection Protocol**
Updated July 2020
One collector is currently operating on the roof of LSA. A key is located in GWC 681 in the desk drawer and is labeled "LSA Roof" with white lab tape.
### **Supplies:**
* Buckets (weighed, bagged, and labeled)
* Lids (weighed, bagged, and labeled)
* Backpack with ADP field datasheets and instructions, cleaning cloths/sponges, sandpaper, wire brush and/or water bottle, screwdriver, mineral oil, and Vaseline
### **Field Procedure/Sampling Schedule:**
Dry buckets are changed monthly, all on the same day (the third Tuesday of each month).
Wet buckets are collected/changed according to the following rules:
* Collect a sample after EVERY rainfall event.
* If a series of storms is expected over a period of days, wait until the storms are over to collect.
Once collected, the buckets should be prepped right away. If this is not possible, then the buckets may be placed in the cold room in GWC 675 to wait for prepping.
Be careful not to contaminate the old or new bucket. If the sample is spilled or the bucket is dropped at any time, especially if the rim of the bucket or lid contacts any surfaces, make a note.
### **Changing the wet side bucket:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, amount of rain in the rain gauge, lid label and weight, old bucket label and weight, new bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
While the roof is still covering the dry side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, if necessary, waiting until the roof moves back to the wet side.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing the dry side bucket:**
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, lid label, old bucket label, new bucket label, and contaminants.
Inspect the battery in its housing and check the voltage with a volt meter and record on the datasheet. The voltage should be above 13V. If not, it may be time to replace the battery with a new one.
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. See the troubleshooting section below if there is a problem.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Before replacing the dry bucket and with the roof covering the wet side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing both buckets:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record initials, time, date, amount of rain in rain gauge, lid label and weight, old wet bucket label and weight, new wet bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record the lid label, old dry bucket label, new dry bucket label, and contaminants.
Now that both buckets have been removed, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample buckets.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Again, short out the sensor with a few drops of water or wire brush, and then using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Place the securely closed buckets into the garbage bags the clean buckets were in.
If the sensor, motor, or battery is not working and the roof has stuck allowing water in the dry or both sides, pour all samples into the dry bucket, record on the field datasheet that this is a "bulk" sample (i.e., wet and dry composition combined), and then put the collector in "bulk" sample mode (wet bucket is exposed). If the collector motor box will not move the lid, reach under the main frame of the collector and push the clutch arm counter-clockwise. The clutch will disengage and the lid mechanism will be free of the drive system. Manually position the lid over the dry side bucket and use the bucket retaining springs to secure the lid. Disconnect the collector from the power supply.
### **Troubleshooting Tips for ADP Collector:**
If the collector fails to operate, try the following:
* Check the power source.
* Battery: Check for corrosion of the battery cable connections at the battery and at the motor. Many times the connectors at the battery become corroded, resulting in a bad connection. Sanding the connectors clean will solve this problem. Check the battery voltage; the battery may be dead. If the connectors at the motor are the problem, sand clean, apply Vaseline and reconnect.
* Check the wet sensor. Replace with a spare and see if the collector operates. If not, then the motor is bad and must be replaced. A faulty motor box is usually indicated by one of four things:
* Upon a "wet" sense, the roof cycles continuously back and forth.
* Upon a "dry" sense, the roof cycles continuously back and forth.
* The motor does not run at all, even when the crank arm is placed in a vertical position by hand.
* The temperature of the sensor plate is HOT when the collector is in the "dry" collection state.
All of these conditions indicate that one of the mercury wetted switches within the motor is faulty. Unfortunately, Aerochem Metrics, the company that manufactured the ADP collectors, no longer exists and collectors of this type are no longer made. The only remedy is to remove the motor, which comes off as a unit, and replace it with a spare. If no spares are available, then it may be necessary to purchase the new-type collector manufactured by N-CON Systems [here](http://www.n-con.com/Products/ads.html).
# **ADP Sample Processing Protocol**
Updated July 2020
Upon returning from the field, remove the buckets from garbage bags and wipe any soil/debris off the top, bottom, and sides of each bucket. When necessary, buckets can be left in the cold room for up to a week before weighing.
## **Dry collection:**
Wearing nitrile gloves, open the dry bucket and remove any contamination (insects, bird droppings, etc.) with 10% HCl-washed and nanopure-rinsed forceps. Ensure contaminants are noted on the field datasheet.
Using a Nanopure-rinsed 500mL graduated cylinder, add 500mL of nanopure water to the bucket.
With the lid off, swirl the water around the inside of the bucket as high as possible without any risk of spillage. Rest the lid loosely on top of the bucket (do not push lid down).
Place the bucket on the reciprocal shaker in GWC 681 for 10 minutes.
Rinse a 500mL plastic 10% HCl-rinsed bottle with a small amount of sample (~5-10mL), then pour the remaining sample from the bucket into the bottle. Record the HCl bottle number on the field datasheet.
Replace the lid on the bucket and set aside to be cleaned.
### **For ammonium (NH<sub>4</sub><sup>+</sup>) and nitrate (NO<sub>3</sub><sup>-</sup>) analysis:**
Label an ammonium centrifuge tube with "ADP", "site-D" (for dry collection, "site-W" for wet collection), and date.
Rinse the tube with a small amount of sample and then fill and cap.
Centrifuge at 8000rpm for 10min (make sure rotor is balanced).
Place the tubes in a tube rack labeled with the date and "ADP-N", then store the tubes in the freezer in GWC 630 for analysis on the Lachat flow-injection analyzer.
### **For Dissolved Organic Carbon (DOC) analysis:**
Using a clean, Nanopure-rinsed 25mm filter apparatus with an ashed GF/F 25mm filter, filter a small amount of sample (~5mL) to rinse and then discard.
Label a 40 mL glass DOC vial with ‘ADP’, ‘site-D’ (for dry collection; ‘site-W’ for wet), and the date.
Filter ~50 ml of sample. Rinse the vial with filtered sample, then discard the rinse and fill the DOC vial with the remaining filtrate until almost full.
Rinse the filter apparatus with nanopure before beginning the next sample.
Acidify each sample with 2 drops of concentrated HCl.
Place the samples in a tube rack labeled with the date and "ADP DOC-Acidified" on a strip of tape, then store the vials in the cold room in GWC 675 until the samples can be run (preferably within 24hr).
### **For anion and cation analysis:**
Label two sterile 50mL centrifuge tubes with "ADP", "site-D" (for dry collection, "site-W" for wet), and "anions" or "cations" (one of each).
Using a clean, Nanopure-rinsed 47mm filter apparatus with a Supor-450 47mm membrane filter, filter a small amount of sample (~15mL) to rinse and then discard.
Filter enough of the remaining sample to rinse and fill the two 50mL centrifuge tubes.
Fill the anion tube with filtrate, then cap. The centrifuge tubes are sterile so do not need to be rinsed with sample prior to filling.
Repeat with the cation tube.
Rinse the filter apparatus with Nanopure before beginning the next sample.
Place the anion samples in a Styrofoam tube holder labeled with the date and "ADP Anions" on a strip of tape, then store the tubes in the cold room in the freezer in GWC669 until samples can be run (preferably within 24-48 hours of collection for reactive species).
Place the cation samples in a Styrofoam tube holder labeled with the date and "ADP Cations-Acidified" on a strip of tape and then acidify the cation samples as follows:
* Place an empty 50mL centrifuge tube on the balance and tare.
* Weigh the cation centrifuge tube on the tared balance and record the sample weight (in grams) on the datasheet.
* Multiply the weight by 20. The result equals the amount (in microliters) of trace metal grade nitric acid to add. Record this volume on the datasheet.
* Under the hood, use an adjustable pipette with a filtered pipette tip to add the acid to the samples.
* Once acidified, the samples are stored on the bench in the storage room in GWC 681.
## **Wet collection:**
Notes:
If there is less than ~10mL of sample in the wet bucket, note this on the datasheet and do not process the sample. If the sample bottle volume is limited (i.e., 10 < 140mL) or lost, note the unprocessed subsamples on the field datasheet.
In cases when there is not enough rain to complete all of the analyses, the sampling priority is as follows: ammonium/nitrate, DOC, anions, cations, pH. See the following table for volume requirements for each analysis:
Remove the wet collection bucket from the garbage bag and wipe any soil/debris off the top, bottom, and sides of each bucket.
Tare the 12kg balance in GWC 681 and weigh each bucket.
Record the total weight (in kg) on the field datasheet. Subtract the lid and bucket weights from the total weight and record the net sample weight (in g) on the field datasheet.
Perform the analyses described above for the dry collection protocol.
After the last step of the dry collection protocol, measure the pH of the sample remaining in the 500mL 10% HCl-rinsed bottle using the pH meter in GWC 677 and record on the datasheet.
## **Lab cleanup:**
Rinse, dry, and 10% HCl-wash any glassware used.
Clean buckets and lids according to the "ADP Bucket/Lid Inspection/Rinsing, Bagging, and New Bucket Prep" protocol.
Ensure an adequate supply of ashed 25mm GF/F filters (4hr in muffle furnace at 500°C).
Filters can be removed from the furnace the following day.
Note: Bulk Samples - If dry buckets have collected rainwater due to a collector malfunction, process this water as a bulk sample (see ADP Sample Collection Protocol). Add the water from the wet bucket to the dry bucket, then weigh and process as a wet bucket EXCEPT swirl the sample as you would a dry bucket before proceeding.
# **ADP Bucket Inspection/Rinsing, Bagging and New Bucket Prep**
Updated July 2020
### **Inspection:**
* Wipe any moisture, dirt, or debris off the outside of all buckets and lids with a dry paper towel.
* Inspect buckets/lids for cracks, chips, stains, and rust on the bucket handle. If the weight appears to have changed by these means but the buckets/lids are still good, be sure to reweigh the buckets/lids with the 12kg balance in GWC 681, relabel with a Sharpie, and circle any defects. The buckets also change weight over time due to outdoor exposure. It is useful to reweigh any used buckets every few months to make sure the weights are accurate; relabel with a Sharpie if necessary.
* Check that the ID and weights are still visible and legible. If necessary, rewrite with a Sharpie.
### **Rinsing:**
* Put on a pair of nitrile gloves and thoroughly rinse them with nanopure water.
* Rinse the exterior of the bucket/lid with nanopure water to loosen any contamination. Use a small scrub brush if necessary.
* Rinse the interior of the bucket/underside of the lid with nanopure water.
* Rinse a natural sponge thoroughly with nanopure water then wipe the interior surface. Use a small scrub brush if necessary.
* Rinse the bucket interior surface with nanopure water four times, 1/4 turn between each rinse.
* Set the bucket upside down on the drying cart or on paper towels on the counter. Place the lid similarly on the drying cart/paper towels with the underside facing downward.
* Buckets/lids will dry within 24hr if air is allowed to circulate inside (e.g., by leaning on a neighboring bucket/lid or overhanging a counter's edge a bit).
### **Bagging:**
* Using 13gal garbage bags for buckets and 4gal garbage bags for lids, place the buckets/lids into new plastic garbage bags by using the outside of the bags as gloves.
* Buckets should have the open end towards the bottom of the bag.
* Squeeze the air out of the bag and close with a twist tie.
### **New bucket prep:**
* Clean new buckets/lids as described above under "Rinsing".
* Fill the bucket with distilled water. While filling, add 1mL of 0.6N HNO<sub>3</sub> solution (38.2mL concentrated HNO<sub>3</sub>/L) using a rinsed pipet tip. Fill the bucket to 2cm below the rim.
* Place a clean lid on top of the bucket and set aside for 7 days to leach.
* After 7 days, clean the bucket/lid again as described under "Rinsing".
* Weigh the bucket/lid with the 12kg balance in GWC 681, recording the ID and weight with a Sharpie twice on the side and once on the bottom of the bucket/twice on the side and once on the top of the lid.
# **ADP Bulk Deposition Funnel Collector**
Updated July 2020
Bulk deposition samples are collected along with ADP wet buckets. If there has been no precipitation during the month, then the funnel and sample bottle should be inspected for damage and, if necessary, replaced with clean ones when the ADP dry bucket is collected. During periods of heavy rainfall, the sample bottle should be collected before it overflows.
Funnels are acid washed with 10% HCl prior to installation. Sample collection bottles are 1gal bottles that have been acid washed with 10% HCl. Once clean and dry, weigh the sample bottle with its cap on on the 12kg balance in GWC 681. Write its weight and ID on the side of the bottle with a Sharpie. The collected sample is routed through looped Tygon tubing between the funnel and bottle and forms a vapor trap to prevent evaporation of the sample. Tygon tubing running from the sample bottle to a 4oz bottle containing nanopure water provides a second vapor trap but allows the sample bottle to breathe during precipitation collection.
In order to prevent bird droppings or insects from entering the funnel and contaminating the sample, a 17in x 17in piece of 10% HCl-washed fiberglass screen is tied to the top of the funnel using thin wire. Additionally, a small 2cm square of 10% HCl-washed blue aquarium filter is placed in the bottom of the funnel on top of the stopper.
Clean funnels are placed in 13gal garbage bags and stored with ADP buckets. Clean 1gal sample bottles are stored in the same area. Other supplies (thin wire, 4oz bottles, Tygon tubing, stoppers, cable ties, Velcro, nanopure water rinse bottle, spare quick connects, screens, and aquarium filters) are stored in a sweater box in the cabinet where the ADP backpack is kept in GWC 639.
The bulk deposition funnel collector is located on the roof of LSA. Access is via a locked gate. The key to the roof lock is kept in the desk drawer in GWC 681 and is labeled "LSA Roof" with white lab tape.
### **Sample collection:**
Inspect funnel for contamination (e.g., bird droppings, insects). If present, continue with the sample collection and funnel/bottle replacement procedures, but discard the contaminated sample. Do not prepare it for analysis.
Replace the screen-covered funnel with a clean one that has been acid washed. Wear nitrile gloves when handling replacement funnels to minimize Na contamination. Also, replace the aquarium filter and rubber stopper in the neck of the funnel with ones that have been acid washed.
Disconnect the tubing from the funnel at the quick connect (on the 1gal bottle cap) and pour about 250mL of nanopure water into the funnel to rinse the tubing. Reconnect the tubing when finished.
Unscrew the cap of the replacement 1gal bottle; put the cap from this bottle on the sample bottle. Put the new bottle on the stand and replace the cap. The easiest way to do this is to screw the bottle onto the cap, making sure the seal is tight. Record the sample bottle number and weight on the ADP field datasheet under "Buckets" under site "Fun". The "Lid" portion of the field sheet will not be used. Note any contaminants on the funnel (e.g. bird droppings, insects) under "Contaminants" on the field sheet. Remember to discard contaminated samples.
Inspect the 4oz bottle and replace with a new one half-filled with nanopure water if necessary. Reuse the holed cap. Make sure the Tygon tubing extends down into the water.
When replacing tubing, bring one 18in-long piece to connect from the funnel to the 1gal bottle and another 23in-long piece to connect from the 1gal bottle to the 4oz bottle. Make sure the tubing that connects the funnel and the 1gal bottle is looped to form a vapor trap. Secure both pieces of tubing to the PVC frame.
Weigh the capped 1gal sample bottle on the 12kg balance in GWC 681 and record the weight on the ADP field datasheet.
Samples should be refrigerated if not processed right away.
Process samples the same as an ADP wet bucket sample.
### **Maintenance:**
Funnels and bottles may become brittle and crack due to repeated acid washings and outdoor exposure. They should be discarded and replaced with new ones.
Tygon tubing will become yellowed and start to break down from outdoor exposure. Dirt may accumulate along the walls of the tubing and algae may also start to grow and discolor the tubing. Replace the tubing at the first sign of any of the above.
### **Ordering information:**
* 311mm diameter LDPE funnels: Fisher #10-349B
* One-hole No. 1 rubber stoppers: Fisher #14-135C
* Tygon tubing 3/16in inside diameter x 1/16in wall thickness: Fisher #15-315-6a
* 1gal bottle: Fisher #02-911-992
* 4oz bottle: Fisher #02-911-958
* 18-24in bonded blue and white pre-filter (coarse): Pure-flo
* Roll of grey fiberglass screen: Home Depot
# **ADP Sample Collection Protocol**
Updated July 2020
One collector is currently operating on the roof of LSA. A key is located in GWC 681 in the desk drawer and is labeled "LSA Roof" with white lab tape.
### **Supplies:**
* Buckets (weighed, bagged, and labeled)
* Lids (weighed, bagged, and labeled)
* Backpack with ADP field datasheets and instructions, cleaning cloths/sponges, sandpaper, wire brush and/or water bottle, screwdriver, mineral oil, and Vaseline
### **Field Procedure/Sampling Schedule:**
Dry buckets are changed monthly, all on the same day (the third Tuesday of each month).
Wet buckets are collected/changed according to the following rules:
* Collect a sample after EVERY rainfall event.
* If a series of storms is expected over a period of days, wait until the storms are over to collect.
Once collected, the buckets should be prepped right away. If this is not possible, then the buckets may be placed in the cold room in GWC 675 to wait for prepping.
Be careful not to contaminate the old or new bucket. If the sample is spilled or the bucket is dropped at any time, especially if the rim of the bucket or lid contacts any surfaces, make a note.
### **Changing the wet side bucket:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, amount of rain in the rain gauge, lid label and weight, old bucket label and weight, new bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
While the roof is still covering the dry side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, if necessary, waiting until the roof moves back to the wet side.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing the dry side bucket:**
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, lid label, old bucket label, new bucket label, and contaminants.
Inspect the battery in its housing and check the voltage with a volt meter and record on the datasheet. The voltage should be above 13V. If not, it may be time to replace the battery with a new one.
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. See the troubleshooting section below if there is a problem.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Before replacing the dry bucket and with the roof covering the wet side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing both buckets:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record initials, time, date, amount of rain in rain gauge, lid label and weight, old wet bucket label and weight, new wet bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record the lid label, old dry bucket label, new dry bucket label, and contaminants.
Now that both buckets have been removed, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample buckets.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Again, short out the sensor with a few drops of water or wire brush, and then using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Place the securely closed buckets into the garbage bags the clean buckets were in.
If the sensor, motor, or battery is not working and the roof has stuck allowing water in the dry or both sides, pour all samples into the dry bucket, record on the field datasheet that this is a "bulk" sample (i.e., wet and dry composition combined), and then put the collector in "bulk" sample mode (wet bucket is exposed). If the collector motor box will not move the lid, reach under the main frame of the collector and push the clutch arm counter-clockwise. The clutch will disengage and the lid mechanism will be free of the drive system. Manually position the lid over the dry side bucket and use the bucket retaining springs to secure the lid. Disconnect the collector from the power supply.
### **Troubleshooting Tips for ADP Collector:**
If the collector fails to operate, try the following:
* Check the power source.
* Battery: Check for corrosion of the battery cable connections at the battery and at the motor. Many times the connectors at the battery become corroded, resulting in a bad connection. Sanding the connectors clean will solve this problem. Check the battery voltage; the battery may be dead. If the connectors at the motor are the problem, sand clean, apply Vaseline and reconnect.
* Check the wet sensor. Replace with a spare and see if the collector operates. If not, then the motor is bad and must be replaced. A faulty motor box is usually indicated by one of four things:
* Upon a "wet" sense, the roof cycles continuously back and forth.
* Upon a "dry" sense, the roof cycles continuously back and forth.
* The motor does not run at all, even when the crank arm is placed in a vertical position by hand.
* The temperature of the sensor plate is HOT when the collector is in the "dry" collection state.
All of these conditions indicate that one of the mercury wetted switches within the motor is faulty. Unfortunately, Aerochem Metrics, the company that manufactured the ADP collectors, no longer exists and collectors of this type are no longer made. The only remedy is to remove the motor, which comes off as a unit, and replace it with a spare. If no spares are available, then it may be necessary to purchase the new-type collector manufactured by N-CON Systems [here](http://www.n-con.com/Products/ads.html).
# **ADP Sample Processing Protocol**
Updated July 2020
Upon returning from the field, remove the buckets from garbage bags and wipe any soil/debris off the top, bottom, and sides of each bucket. When necessary, buckets can be left in the cold room for up to a week before weighing.
## **Dry collection:**
Wearing nitrile gloves, open the dry bucket and remove any contamination (insects, bird droppings, etc.) with 10% HCl-washed and nanopure-rinsed forceps. Ensure contaminants are noted on the field datasheet.
Using a Nanopure-rinsed 500mL graduated cylinder, add 500mL of nanopure water to the bucket.
With the lid off, swirl the water around the inside of the bucket as high as possible without any risk of spillage. Rest the lid loosely on top of the bucket (do not push lid down).
Place the bucket on the reciprocal shaker in GWC 681 for 10 minutes.
Rinse a 500mL plastic 10% HCl-rinsed bottle with a small amount of sample (~5-10mL), then pour the remaining sample from the bucket into the bottle. Record the HCl bottle number on the field datasheet.
Replace the lid on the bucket and set aside to be cleaned.
### **For ammonium (NH<sub>4</sub><sup>+</sup>) and nitrate (NO<sub>3</sub><sup>-</sup>) analysis:**
Label an ammonium centrifuge tube with "ADP", "site-D" (for dry collection, "site-W" for wet collection), and date.
Rinse the tube with a small amount of sample and then fill and cap.
Centrifuge at 8000rpm for 10min (make sure rotor is balanced).
Place the tubes in a tube rack labeled with the date and "ADP-N", then store the tubes in the freezer in GWC 630 for analysis on the Lachat flow-injection analyzer.
### **For Dissolved Organic Carbon (DOC) analysis:**
Using a clean, Nanopure-rinsed 25mm filter apparatus with an ashed GF/F 25mm filter, filter a small amount of sample (~5mL) to rinse and then discard.
Label a 40 mL glass DOC vial with ‘ADP’, ‘site-D’ (for dry collection; ‘site-W’ for wet), and the date.
Filter ~50 ml of sample. Rinse the vial with filtered sample, then discard the rinse and fill the DOC vial with the remaining filtrate until almost full.
Rinse the filter apparatus with nanopure before beginning the next sample.
Acidify each sample with 2 drops of concentrated HCl.
Place the samples in a tube rack labeled with the date and "ADP DOC-Acidified" on a strip of tape, then store the vials in the cold room in GWC 675 until the samples can be run (preferably within 24hr).
### **For anion and cation analysis:**
Label two sterile 50mL centrifuge tubes with "ADP", "site-D" (for dry collection, "site-W" for wet), and "anions" or "cations" (one of each).
Using a clean, Nanopure-rinsed 47mm filter apparatus with a Supor-450 47mm membrane filter, filter a small amount of sample (~15mL) to rinse and then discard.
Filter enough of the remaining sample to rinse and fill the two 50mL centrifuge tubes.
Fill the anion tube with filtrate, then cap. The centrifuge tubes are sterile so do not need to be rinsed with sample prior to filling.
Repeat with the cation tube.
Rinse the filter apparatus with Nanopure before beginning the next sample.
Place the anion samples in a Styrofoam tube holder labeled with the date and "ADP Anions" on a strip of tape, then store the tubes in the cold room in the freezer in GWC669 until samples can be run (preferably within 24-48 hours of collection for reactive species).
Place the cation samples in a Styrofoam tube holder labeled with the date and "ADP Cations-Acidified" on a strip of tape and then acidify the cation samples as follows:
* Place an empty 50mL centrifuge tube on the balance and tare.
* Weigh the cation centrifuge tube on the tared balance and record the sample weight (in grams) on the datasheet.
* Multiply the weight by 20. The result equals the amount (in microliters) of trace metal grade nitric acid to add. Record this volume on the datasheet.
* Under the hood, use an adjustable pipette with a filtered pipette tip to add the acid to the samples.
* Once acidified, the samples are stored on the bench in the storage room in GWC 681.
## **Wet collection:**
Notes:
If there is less than ~10mL of sample in the wet bucket, note this on the datasheet and do not process the sample. If the sample bottle volume is limited (i.e., 10 < 140mL) or lost, note the unprocessed subsamples on the field datasheet.
In cases when there is not enough rain to complete all of the analyses, the sampling priority is as follows: ammonium/nitrate, DOC, anions, cations, pH. See the following table for volume requirements for each analysis:
Remove the wet collection bucket from the garbage bag and wipe any soil/debris off the top, bottom, and sides of each bucket.
Tare the 12kg balance in GWC 681 and weigh each bucket.
Record the total weight (in kg) on the field datasheet. Subtract the lid and bucket weights from the total weight and record the net sample weight (in g) on the field datasheet.
Perform the analyses described above for the dry collection protocol.
After the last step of the dry collection protocol, measure the pH of the sample remaining in the 500mL 10% HCl-rinsed bottle using the pH meter in GWC 677 and record on the datasheet.
## **Lab cleanup:**
Rinse, dry, and 10% HCl-wash any glassware used.
Clean buckets and lids according to the "ADP Bucket/Lid Inspection/Rinsing, Bagging, and New Bucket Prep" protocol.
Ensure an adequate supply of ashed 25mm GF/F filters (4hr in muffle furnace at 500°C).
Filters can be removed from the furnace the following day.
Note: Bulk Samples - If dry buckets have collected rainwater due to a collector malfunction, process this water as a bulk sample (see ADP Sample Collection Protocol). Add the water from the wet bucket to the dry bucket, then weigh and process as a wet bucket EXCEPT swirl the sample as you would a dry bucket before proceeding.
# **ADP Bucket Inspection/Rinsing, Bagging and New Bucket Prep**
Updated July 2020
### **Inspection:**
* Wipe any moisture, dirt, or debris off the outside of all buckets and lids with a dry paper towel.
* Inspect buckets/lids for cracks, chips, stains, and rust on the bucket handle. If the weight appears to have changed by these means but the buckets/lids are still good, be sure to reweigh the buckets/lids with the 12kg balance in GWC 681, relabel with a Sharpie, and circle any defects. The buckets also change weight over time due to outdoor exposure. It is useful to reweigh any used buckets every few months to make sure the weights are accurate; relabel with a Sharpie if necessary.
* Check that the ID and weights are still visible and legible. If necessary, rewrite with a Sharpie.
### **Rinsing:**
* Put on a pair of nitrile gloves and thoroughly rinse them with nanopure water.
* Rinse the exterior of the bucket/lid with nanopure water to loosen any contamination. Use a small scrub brush if necessary.
* Rinse the interior of the bucket/underside of the lid with nanopure water.
* Rinse a natural sponge thoroughly with nanopure water then wipe the interior surface. Use a small scrub brush if necessary.
* Rinse the bucket interior surface with nanopure water four times, 1/4 turn between each rinse.
* Set the bucket upside down on the drying cart or on paper towels on the counter. Place the lid similarly on the drying cart/paper towels with the underside facing downward.
* Buckets/lids will dry within 24hr if air is allowed to circulate inside (e.g., by leaning on a neighboring bucket/lid or overhanging a counter's edge a bit).
### **Bagging:**
* Using 13gal garbage bags for buckets and 4gal garbage bags for lids, place the buckets/lids into new plastic garbage bags by using the outside of the bags as gloves.
* Buckets should have the open end towards the bottom of the bag.
* Squeeze the air out of the bag and close with a twist tie.
### **New bucket prep:**
* Clean new buckets/lids as described above under "Rinsing".
* Fill the bucket with distilled water. While filling, add 1mL of 0.6N HNO<sub>3</sub> solution (38.2mL concentrated HNO<sub>3</sub>/L) using a rinsed pipet tip. Fill the bucket to 2cm below the rim.
* Place a clean lid on top of the bucket and set aside for 7 days to leach.
* After 7 days, clean the bucket/lid again as described under "Rinsing".
* Weigh the bucket/lid with the 12kg balance in GWC 681, recording the ID and weight with a Sharpie twice on the side and once on the bottom of the bucket/twice on the side and once on the top of the lid.
# **ADP Bulk Deposition Funnel Collector**
Updated July 2020
Bulk deposition samples are collected along with ADP wet buckets. If there has been no precipitation during the month, then the funnel and sample bottle should be inspected for damage and, if necessary, replaced with clean ones when the ADP dry bucket is collected. During periods of heavy rainfall, the sample bottle should be collected before it overflows.
Funnels are acid washed with 10% HCl prior to installation. Sample collection bottles are 1gal bottles that have been acid washed with 10% HCl. Once clean and dry, weigh the sample bottle with its cap on on the 12kg balance in GWC 681. Write its weight and ID on the side of the bottle with a Sharpie. The collected sample is routed through looped Tygon tubing between the funnel and bottle and forms a vapor trap to prevent evaporation of the sample. Tygon tubing running from the sample bottle to a 4oz bottle containing nanopure water provides a second vapor trap but allows the sample bottle to breathe during precipitation collection.
In order to prevent bird droppings or insects from entering the funnel and contaminating the sample, a 17in x 17in piece of 10% HCl-washed fiberglass screen is tied to the top of the funnel using thin wire. Additionally, a small 2cm square of 10% HCl-washed blue aquarium filter is placed in the bottom of the funnel on top of the stopper.
Clean funnels are placed in 13gal garbage bags and stored with ADP buckets. Clean 1gal sample bottles are stored in the same area. Other supplies (thin wire, 4oz bottles, Tygon tubing, stoppers, cable ties, Velcro, nanopure water rinse bottle, spare quick connects, screens, and aquarium filters) are stored in a sweater box in the cabinet where the ADP backpack is kept in GWC 639.
The bulk deposition funnel collector is located on the roof of LSA. Access is via a locked gate. The key to the roof lock is kept in the desk drawer in GWC 681 and is labeled "LSA Roof" with white lab tape.
### **Sample collection:**
Inspect funnel for contamination (e.g., bird droppings, insects). If present, continue with the sample collection and funnel/bottle replacement procedures, but discard the contaminated sample. Do not prepare it for analysis.
Replace the screen-covered funnel with a clean one that has been acid washed. Wear nitrile gloves when handling replacement funnels to minimize Na contamination. Also, replace the aquarium filter and rubber stopper in the neck of the funnel with ones that have been acid washed.
Disconnect the tubing from the funnel at the quick connect (on the 1gal bottle cap) and pour about 250mL of nanopure water into the funnel to rinse the tubing. Reconnect the tubing when finished.
Unscrew the cap of the replacement 1gal bottle; put the cap from this bottle on the sample bottle. Put the new bottle on the stand and replace the cap. The easiest way to do this is to screw the bottle onto the cap, making sure the seal is tight. Record the sample bottle number and weight on the ADP field datasheet under "Buckets" under site "Fun". The "Lid" portion of the field sheet will not be used. Note any contaminants on the funnel (e.g. bird droppings, insects) under "Contaminants" on the field sheet. Remember to discard contaminated samples.
Inspect the 4oz bottle and replace with a new one half-filled with nanopure water if necessary. Reuse the holed cap. Make sure the Tygon tubing extends down into the water.
When replacing tubing, bring one 18in-long piece to connect from the funnel to the 1gal bottle and another 23in-long piece to connect from the 1gal bottle to the 4oz bottle. Make sure the tubing that connects the funnel and the 1gal bottle is looped to form a vapor trap. Secure both pieces of tubing to the PVC frame.
Weigh the capped 1gal sample bottle on the 12kg balance in GWC 681 and record the weight on the ADP field datasheet.
Samples should be refrigerated if not processed right away.
Process samples the same as an ADP wet bucket sample.
### **Maintenance:**
Funnels and bottles may become brittle and crack due to repeated acid washings and outdoor exposure. They should be discarded and replaced with new ones.
Tygon tubing will become yellowed and start to break down from outdoor exposure. Dirt may accumulate along the walls of the tubing and algae may also start to grow and discolor the tubing. Replace the tubing at the first sign of any of the above.
### **Ordering information:**
* 311mm diameter LDPE funnels: Fisher #10-349B
* One-hole No. 1 rubber stoppers: Fisher #14-135C
* Tygon tubing 3/16in inside diameter x 1/16in wall thickness: Fisher #15-315-6a
* 1gal bottle: Fisher #02-911-992
* 4oz bottle: Fisher #02-911-958
* 18-24in bonded blue and white pre-filter (coarse): Pure-flo
* Roll of grey fiberglass screen: Home Depot
# **ADP Sample Collection Protocol**
Updated July 2020
One collector is currently operating on the roof of LSA. A key is located in GWC 681 in the desk drawer and is labeled "LSA Roof" with white lab tape.
### **Supplies:**
* Buckets (weighed, bagged, and labeled)
* Lids (weighed, bagged, and labeled)
* Backpack with ADP field datasheets and instructions, cleaning cloths/sponges, sandpaper, wire brush and/or water bottle, screwdriver, mineral oil, and Vaseline
### **Field Procedure/Sampling Schedule:**
Dry buckets are changed monthly, all on the same day (the third Tuesday of each month).
Wet buckets are collected/changed according to the following rules:
* Collect a sample after EVERY rainfall event.
* If a series of storms is expected over a period of days, wait until the storms are over to collect.
Once collected, the buckets should be prepped right away. If this is not possible, then the buckets may be placed in the cold room in GWC 675 to wait for prepping.
Be careful not to contaminate the old or new bucket. If the sample is spilled or the bucket is dropped at any time, especially if the rim of the bucket or lid contacts any surfaces, make a note.
### **Changing the wet side bucket:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, amount of rain in the rain gauge, lid label and weight, old bucket label and weight, new bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
While the roof is still covering the dry side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, if necessary, waiting until the roof moves back to the wet side.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing the dry side bucket:**
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the field datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the datasheet, record initials, time, date, lid label, old bucket label, new bucket label, and contaminants.
Inspect the battery in its housing and check the voltage with a volt meter and record on the datasheet. The voltage should be above 13V. If not, it may be time to replace the battery with a new one.
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. See the troubleshooting section below if there is a problem.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Before replacing the dry bucket and with the roof covering the wet side bucket, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample bucket.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Place the securely closed bucket into the garbage bag the clean bucket was in.
### **Changing both buckets:**
To ensure the collector is working properly, short out the sensor with a few drops of water or the wire brush and watch the roof to see if it moves freely and evenly with little motor noise. The lid seal pad should rest snugly on the dry side bucket. See the troubleshooting section below if there is a problem.
Examine the wet side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the wet side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record initials, time, date, amount of rain in rain gauge, lid label and weight, old wet bucket label and weight, new wet bucket label, and contaminants.
After recording the amount of rain, empty the contents of the rain gauge.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Examine the dry side bucket carefully for contamination such as soil, insects, bird droppings, etc. Record signs of contamination on the datasheet.
Using the garbage bag the lid is in as a glove, place the lid on the dry side bucket.
Remove the bucket and lid from the collector, and snap the lid on tightly.
On the field datasheet, record the lid label, old dry bucket label, new dry bucket label, and contaminants.
Now that both buckets have been removed, wipe the top of the roof, sensor, and around the buckets to remove bird droppings, dirt, etc. that could contaminate the sample buckets.
Using the garbage bag as a glove, place the new dry side bucket in the bucket holder.
Again, short out the sensor with a few drops of water or wire brush, and then using the garbage bag as a glove, place the new wet side bucket in the bucket holder.
Blow off any excess water on the sensor, waiting until the roof moves back to the wet side.
Place the securely closed buckets into the garbage bags the clean buckets were in.
If the sensor, motor, or battery is not working and the roof has stuck allowing water in the dry or both sides, pour all samples into the dry bucket, record on the field datasheet that this is a "bulk" sample (i.e., wet and dry composition combined), and then put the collector in "bulk" sample mode (wet bucket is exposed). If the collector motor box will not move the lid, reach under the main frame of the collector and push the clutch arm counter-clockwise. The clutch will disengage and the lid mechanism will be free of the drive system. Manually position the lid over the dry side bucket and use the bucket retaining springs to secure the lid. Disconnect the collector from the power supply.
### **Troubleshooting Tips for ADP Collector:**
If the collector fails to operate, try the following:
* Check the power source.
* Battery: Check for corrosion of the battery cable connections at the battery and at the motor. Many times the connectors at the battery become corroded, resulting in a bad connection. Sanding the connectors clean will solve this problem. Check the battery voltage; the battery may be dead. If the connectors at the motor are the problem, sand clean, apply Vaseline and reconnect.
* Check the wet sensor. Replace with a spare and see if the collector operates. If not, then the motor is bad and must be replaced. A faulty motor box is usually indicated by one of four things:
* Upon a "wet" sense, the roof cycles continuously back and forth.
* Upon a "dry" sense, the roof cycles continuously back and forth.
* The motor does not run at all, even when the crank arm is placed in a vertical position by hand.
* The temperature of the sensor plate is HOT when the collector is in the "dry" collection state.
All of these conditions indicate that one of the mercury wetted switches within the motor is faulty. Unfortunately, Aerochem Metrics, the company that manufactured the ADP collectors, no longer exists and collectors of this type are no longer made. The only remedy is to remove the motor, which comes off as a unit, and replace it with a spare. If no spares are available, then it may be necessary to purchase the new-type collector manufactured by N-CON Systems [here](http://www.n-con.com/Products/ads.html).
# **ADP Sample Processing Protocol**
Updated July 2020
Upon returning from the field, remove the buckets from garbage bags and wipe any soil/debris off the top, bottom, and sides of each bucket. When necessary, buckets can be left in the cold room for up to a week before weighing.
## **Dry collection:**
Wearing nitrile gloves, open the dry bucket and remove any contamination (insects, bird droppings, etc.) with 10% HCl-washed and nanopure-rinsed forceps. Ensure contaminants are noted on the field datasheet.
Using a Nanopure-rinsed 500mL graduated cylinder, add 500mL of nanopure water to the bucket.
With the lid off, swirl the water around the inside of the bucket as high as possible without any risk of spillage. Rest the lid loosely on top of the bucket (do not push lid down).
Place the bucket on the reciprocal shaker in GWC 681 for 10 minutes.
Rinse a 500mL plastic 10% HCl-rinsed bottle with a small amount of sample (~5-10mL), then pour the remaining sample from the bucket into the bottle. Record the HCl bottle number on the field datasheet.
Replace the lid on the bucket and set aside to be cleaned.
### **For ammonium (NH<sub>4</sub><sup>+</sup>) and nitrate (NO<sub>3</sub><sup>-</sup>) analysis:**
Label an ammonium centrifuge tube with "ADP", "site-D" (for dry collection, "site-W" for wet collection), and date.
Rinse the tube with a small amount of sample and then fill and cap.
Centrifuge at 8000rpm for 10min (make sure rotor is balanced).
Place the tubes in a tube rack labeled with the date and "ADP-N", then store the tubes in the freezer in GWC 630 for analysis on the Lachat flow-injection analyzer.
### **For Dissolved Organic Carbon (DOC) analysis:**
Using a clean, Nanopure-rinsed 25mm filter apparatus with an ashed GF/F 25mm filter, filter a small amount of sample (~5mL) to rinse and then discard.
Label a 40 mL glass DOC vial with ‘ADP’, ‘site-D’ (for dry collection; ‘site-W’ for wet), and the date.
Filter ~50 ml of sample. Rinse the vial with filtered sample, then discard the rinse and fill the DOC vial with the remaining filtrate until almost full.
Rinse the filter apparatus with nanopure before beginning the next sample.
Acidify each sample with 2 drops of concentrated HCl.
Place the samples in a tube rack labeled with the date and "ADP DOC-Acidified" on a strip of tape, then store the vials in the cold room in GWC 675 until the samples can be run (preferably within 24hr).
### **For anion and cation analysis:**
Label two sterile 50mL centrifuge tubes with "ADP", "site-D" (for dry collection, "site-W" for wet), and "anions" or "cations" (one of each).
Using a clean, Nanopure-rinsed 47mm filter apparatus with a Supor-450 47mm membrane filter, filter a small amount of sample (~15mL) to rinse and then discard.
Filter enough of the remaining sample to rinse and fill the two 50mL centrifuge tubes.
Fill the anion tube with filtrate, then cap. The centrifuge tubes are sterile so do not need to be rinsed with sample prior to filling.
Repeat with the cation tube.
Rinse the filter apparatus with Nanopure before beginning the next sample.
Place the anion samples in a Styrofoam tube holder labeled with the date and "ADP Anions" on a strip of tape, then store the tubes in the cold room in the freezer in GWC669 until samples can be run (preferably within 24-48 hours of collection for reactive species).
Place the cation samples in a Styrofoam tube holder labeled with the date and "ADP Cations-Acidified" on a strip of tape and then acidify the cation samples as follows:
* Place an empty 50mL centrifuge tube on the balance and tare.
* Weigh the cation centrifuge tube on the tared balance and record the sample weight (in grams) on the datasheet.
* Multiply the weight by 20. The result equals the amount (in microliters) of trace metal grade nitric acid to add. Record this volume on the datasheet.
* Under the hood, use an adjustable pipette with a filtered pipette tip to add the acid to the samples.
* Once acidified, the samples are stored on the bench in the storage room in GWC 681.
## **Wet collection:**
Notes:
If there is less than ~10mL of sample in the wet bucket, note this on the datasheet and do not process the sample. If the sample bottle volume is limited (i.e., 10 < 140mL) or lost, note the unprocessed subsamples on the field datasheet.
In cases when there is not enough rain to complete all of the analyses, the sampling priority is as follows: ammonium/nitrate, DOC, anions, cations, pH. See the following table for volume requirements for each analysis:
Remove the wet collection bucket from the garbage bag and wipe any soil/debris off the top, bottom, and sides of each bucket.
Tare the 12kg balance in GWC 681 and weigh each bucket.
Record the total weight (in kg) on the field datasheet. Subtract the lid and bucket weights from the total weight and record the net sample weight (in g) on the field datasheet.
Perform the analyses described above for the dry collection protocol.
After the last step of the dry collection protocol, measure the pH of the sample remaining in the 500mL 10% HCl-rinsed bottle using the pH meter in GWC 677 and record on the datasheet.
## **Lab cleanup:**
Rinse, dry, and 10% HCl-wash any glassware used.
Clean buckets and lids according to the "ADP Bucket/Lid Inspection/Rinsing, Bagging, and New Bucket Prep" protocol.
Ensure an adequate supply of ashed 25mm GF/F filters (4hr in muffle furnace at 500°C).
Filters can be removed from the furnace the following day.
Note: Bulk Samples - If dry buckets have collected rainwater due to a collector malfunction, process this water as a bulk sample (see ADP Sample Collection Protocol). Add the water from the wet bucket to the dry bucket, then weigh and process as a wet bucket EXCEPT swirl the sample as you would a dry bucket before proceeding.
