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Enzyme Substrate Testing



  • An EPA testing method using Colilert reagent.
  • An undiluted water sample will be analyzed from the samples collected.
  • The test requires the use of 100 ml of sample. 

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Processing Chemical Analysis Samples

  Don't let the words "processing chemical analysis" overwhelm you! It is so easy once you do it a couple of times! You'll be working from memory before you know it! We will be collecting from FOUR different sites for SUMMER SEMESTER 2021 . You can find the addresses and some photos of the sites under the "SITES" tab.  We are currently running SIX chemical tests on the samples. For SUMMER 2021 , we will be testing for the following: Sulfate HR (High Range) Ammonia Nitrogen HR Nitrate-Nitrogen LR (Low Range) Chlorine (FREE/TOTAL/COMBINED) pH Phosphates Each test has it's own set of very to follow instructions. You can find these instructions in the binder in the lab. They are also listed here on the website for your convenience. Check under CHEMICAL ANALYSIS INSTRUCTIONS in the drop down menu on our site to find them digitally! EXAMPLE #1 ~ SULFATE Turn on calorimeter ENTER into testing menu (it should already be highlighted) Use arrow keys to toggle (an...
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Collecting Microbiology Samples

  Sample Collection/Field Kit E. coli are naturally present in our guts, therefore, we have to avoid any contamination of the samples.  Put on gloves (make sure the glove bag stays closed as much as possible to avoid contaminants). Wipe gloved hands with alcohol. Collect water from 1" below the surface in large bottle and pour into small bottle  (SHAKE VIGOROUSLY)  Label bottles with a sharpie (Please make sure the labels are readable for the  data pe rson) . Once collected, samples are put on ice until the are ready to be processed at the lab. The ice ensures that any bacteria in the sample doesn't grow in the meantime.   **Samples are processed within SIX hours of collection** Rinse large collecting bottle with deionized water for the next site collection (Prevent cross-contamination). Place all dirty gloves and trash in provided paper bag. Keeping the samples cold with icepacks and processing in a timely manner ensures that bacteria don't have time to gr...
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Testing Microbiology Samples

We follow these rules specifically. The process is very easy, but make sure you follow the rules and you'll be performing from memory before you know it!!! Hands must be washed before putting on gloves. Surfaces must be wiped down with sodium hypochlorite (bleach water) before and after testing. Label tray with site number, collection time/date, processing time/date, processor's initials. Retrieve sample and Colilert from refrigerator. Aseptically (just means free of pathogenic microorganisms) add one packet of reagent to the sample. Re-cap bottle and shake until reagent is mostly dissolved. (If sample "flashes blue" it contains excessive chlorine and is invalid for analysis) Pour into Quanti-Tray. Place tray in rubber insert for Quanti-Tray sealer machine. The sealer works like a laminator and seals the backing onto the tray. Feed tray into Quanti-Tray sealer. Place tray into incubator and incubate at 35.0 degrees Celsius for 24 hours .  After incubation, the tray is...
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