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Geotech Mastehead

September 2021


What is ORP?

Oxidation-Reduction Potential (ORP) is a qualitative measurement that determines how oxidizing or reducing an environment is. When it comes to environmental monitoring or remediation, ORP determines the health of an aqueous environment and its ability to break down contamination and biological matter.

  • Oxidation occurs when a substance
    lose electrons
  • Reduction occurs when a substance gains electrons

ORP is measured with water quality instrumentation and sensors using low voltage between a platinum and reference electrode. ORP/Redox is expressed in millivolt (mV) units, in which Oxidizing environments are indicated by a positive reading and Reducingenvironments display negative readings.

ORP is generally significant in water which contains a relatively high concentration of a redox-active species, e.g., the salts of many metals (Fe2+, Fe3+) and strong oxidizing (chlorine) and reducing (sulfite ion) agents. Thus, ORP may be utilized to track the metallic pollution in groundwater or surface water.

Biochemical Reactions and Corresponding ORP Values

Biochemical Reaction



cBOD degradation with molecular oxygen
Biological phosphorus removal
Sulfide (H2S) formation
Biological phosphorus release
Acid formation (fermentation)
Methane production


+100 to +350
+50 to +250
+25 to +250
+50 to -50
-50 to -250
-100 to -250
-100 to -225
-175 to -400

Source: ysi.com/parameters/orp-redox
To learn more about instrumentation for measuring ORP or other water quality parameters, reference these industry leading brands sold and supported by Geotech.

Aqualabo DIGISENS Digital Sensors – globally recognized single parameter sensors designed for dedicated monitoring and process control.


In-Situ – single and multiparameter water quality instruments designed for portable and dedicated applications.

Aqua TROLL 500

Seametrics Smart Sensors – single parameter water quality sensors with internal data storage commonly used in unattended monitoring and process control applications.

TempHion pH/ORP/ISE

YSI Pro-Series – versatile handhelds offering single and multiparameter water quality measurements in the field or lab.


Geotech SitePro – water quality data logger and cellular telemetry system providing access to site data and alerts anytime, anywhere.

Geotech SitePro


for guidance
on your next environmental project



Protect Against Airborne Particulate & Viruses

While not everyone has the same sensitivity to wildfire smoke, it's still a good idea to avoid breathing smoke if you can help it. The EPA has reported that the biggest health threat from smoke comes from inhaling microscopic particulate matter distributed throughout the air. When it penetrates deep into your lungs, particulate can cause irritation and progressively result in aggravated chronic heart and lung diseases.

On the heels of one of the worst wildfire seasons on record, air pollution levels are exceeding unhealthy levels. Additionally with elevated rates of transmittable viruses, society is seeking better respiratory protection.

As the manufacturer of Airgami Masks, Geotech has worked closely with the founder of Air99 to perform N95 quantitative fit testing to develop better protection against airborne particulates and viruses. The Airgami mask features:

  • an origami structure that universally conforms to the face comfortably
  • an N95 layered filter with large surface area to promote better air flow
  • reusable materials of construction, meaning it can be washed or even autoclaved

Airgami Respirator

Airgami has been featured in National Geographic "We need better face masks..." and has surpassed Phase 1 of the BARDA/NIOSH Mask Innovation Challenge.

Need a better face mask? Airgami can help. Order at Airgami.life

AQI Basics for Ozone and Particle Pollution
Daily AQI
Levels of
Values of
Description of Air Quality
Green Good 0 to 50 Air quality is satisfactory, and air pollution poses little
or no risk.
Yellow Moderate 51 to 100 Air quality is acceptable. However, there may be a risk for
some people, particularly those who are unusually sensitive
to air pollution.
Orange Unhealthy for Sensitive Groups 101 to 150 Members of sensitive groups may experience health effects.
The general public is less likely to be affected.
Red Unhealthy 151 to 200 Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects.
Purple Very Unhealthy 201 to 300 Health alert: The risk of health effects is increase
for everyone.
Maroon Hazardous 301 and
Health warning of emergency conditions: everyone is more
likely to be affected.
Source: https://www.airnow.gov/aqi/aqi-basics/


RKI Trade-In

Aqualabo  Field Sink

Geotech UAS News


Launching a GeoSwift drone

"I enrolled in the course in preparation for the Part 107 exam. Initially, I thought the value of this training was solely the exam prep. After taking the course, the value is the knowledge, hands on training, and confidence to operate a UAS in the field. Leptron closes the gap between faking your way through or knowing what you are doing and why."
-Nathan W.


The health and safety during this global pandemic is our number one priority during training. To ensure a safe environment for Geotech Drone Flight Training attendees, we continue to follow CDC guidelines to ensure our 3500 square-foot training room is sanitized, seating is distanced, and students receive individual training books and practice aircraft.

Available Course Options:

  • Individual Private Instruction
  • Corporate/Group Courses
  • Public Agency – UAS Program Development
  • Recurrent Exam Preparation



Whether hiring a drone pilot
or seeking to become one, contact Geotech

Enter the Geotech
Product Photo Competition!

Take a Picture

Win valuable prizes and have some fun taking
action shots of people using
Geotech brand equipment!
Take as many pictures as you like!
A $100 gift card will be awarded each month!
Winning photos will be published in
Geotech's monthly electronic newsletter
and on the web site.

What constitutes a winning photograph? We'll award points if your photo...

  • only shows Geotech equipment in use by real workers at real sites,
  • close-ups of the Geotech equipment,
  • equipment being used safely in observance of the health and safety procedures required
  • has companion photos showing as much of the site and surrounding area as possible (with site owner's permission, of course),
  • is well composed: nice framing, interesting background… extra points if the viewer can tell what type of project you were working on,
  • has an unusual twist or story: equipment being used overseas, of an interesting project, or for humanitarian purposes… wildlife or Mother Nature butting/intruding… the perfect shot at sunset, etc.
  • Digital photos only, in jpg or tiff formats, 2 MB or larger if possible.

Entering the competition is easy, go here to review the rules and guidelines and download the entry form. Every entry must be accompanied by a completed Geotech Photo Competition Entry Form.

Look for Geotech at the events listed below.


October 18-20, 2021

94th Annual Technical Exhibition
and Conference


Join us in Chicago for WEFTEC 2021. WEFTEC is recognized as the largest annual water quality exhibition in the world, the expansive show floor provides unparalleled access to the most cutting-edge technologies in the field; serves as a forum for domestic and international business opportunities; and promotes invaluable peer-to-peer networking among registrants. Come visit us and see our latest groundwater equipment at Booth 1612.

For more information

Colorado SWANA Rocky Mountain Chapter

November 1-3, 2021

2021 Colorado Rocky Mountain SWANA Annual Conference

Breathtaking views of the Flatirons within close proximity to the University of Colorado Boulder are just some of the reasons that the 2021 Colorado Rocky Mountain SWANA Annual Conference will be in Boulder.

Attendees will have the opportunity to hear about the latest solid waste topics ranging from recycling to landfill operations. Also, the speakers will be giving updates on what is happening in Colorado solid waste and how it could affect you. The conference is an ideal opportunity to meet and network with your peers and see the latest technology in the exhibit area.

For more information


November 1-4, 2021


The Route to Sustainable Strength

SWANA has re-engineered WASTECON into an executive leadership summit. They will be looking at leadership and management concepts through the lens of municipal solid waste management. Hear from renowned industry leaders and new voices about how they are creating their own "Route to Sustainable Strength". Explore topics such as diversity, equity & inclusion; how waste can be an economic driver for your community; how to fulfill your city's leaders' commitments to environmental improvements; and much more.

Geotech will be in Booth #513 to show and demonstrate our latest landfill equipment. Make sure you don't miss this must-attend event!

For more information

National Ground Water Association
Groundwater Week

December 14-16, 2021

NGWA Groundwater Week 2021

Navigate the future of the industry this
December at Groundwater Week 2021!

Groundwater Week is the one event where thousands of professionals from all sectors of the groundwater industry come together to discover solutions to current and future challenges.

When at the event please come by and visit us at Booth 429.

For more information

Geotech Sales & Service Locations
With Transit Zones

Geotech Sales & Service Locations

2650 East 40th Avenue
Denver, Colorado 80205
Phone: 1-800-833-7958
Local: 303-320-4764
Fax: 303-322-7242
E-mail: sales@geotechenv.com

4620 Northgate Boulevard, Suite 170
Sacramento, California 95834
Phone: 1-800-557-5325
Local: 916-922-2900
Fax: 303-322-7242

155 East Liberty Avenue, Suite A
Anaheim, California 92801
Phone: 1-800-295-5325
Local: 714-998-6788
Fax: 303-322-7242

12165 Metro Parkway, Unit 25B
Fort Myers, Florida 33966
Phone: 1-800-304-5325
Local: 239-476-8891
Fax: 303-322-7242

3125 Pine Tree Road, Suite 3D
Lansing, Michigan 48911
Phone: 1-800-275-5325
Local: 517-394-8328
Fax: 303-322-7242

2517 Noblin Road, Suite 103
Raleigh, North Carolina 27604
Phone: 1-800-293-5325
Local: 919-876-1535
Fax: 303-322-7242

1600 North Interstate 35e, Suite 114
Carrollton, Texas 75006-381
Phone: 1-800-276-5325
Local: 972-245-6575
Fax: 303-322-7242

25 Tigan Street, Suite 20
Winooski, Vermont 05404
Phone: 1-800-558-5325
Local: 802-651-3050
Fax: 303-322-7242

8910 122nd Avenue N.E.
Kirkland, Washington 98033
Phone: 1-800-314-5325
Local: 425-658-7300
Fax: 303-322-7242

C/Francesc Ferrer i Guàrdia Local 19
08100 Mollet del Vallés (Barcelona) Spain
Tel: 93 5445937
Fax: 93 5700535
E-mail: ventas@geotechenv.com


No. 12 Yumin Road, Yuanchenxin Bldg. E2, Suite 2406
Chaoyang District, Beijing, China 100029
Phone: 010-8225-1190
Local: 86-10-8225-1190
Fax: 86-10-8225-1957
E-mail: beijing@geotechenv.com


To contact Geotech:
Phone: 1-800-833-7958   E-mail: sales@geotechenv.com   Fax: 303-322-7242

Prices and promotions mentioned in this newsletter are valid through September 30, 2021.
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Some items may not be immediately available at the time you receive this newsletter, call for details.
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