Using Biochar to Manage Harmful Algae Blooms In Croke Reservoir. John Slattery City of Northglenn Parks Department

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1 Using Biochar to Manage Harmful Algae Blooms In Croke Reservoir John Slattery City of Northglenn Parks Department

2 Croke Reservoir 106 th Avenue and Huron Street Northglenn, Colorado Approximately 15.5 Surface Acres No Source of Fresh Water No Flow Through Fed by Storm Water Run-off Only Lake Is Aerated

3 Lake Depths Most of the Lake is Less than 5 Feet Deep

4 The Blue Greens Love Croke Became a Problem About 5 Years Ago Blooms First Started Showing Up Mid- Summer and Would Dissipate Within a Few Weeks Prior Issues with Filamentous Blooms and Coontail Blooms Starting Earlier and Persisting Longer Last Summer Bloom Began in Mid-May Currently HAB's Are Present the Entire Growing Season Blooms Have Produced High Levels of Microcystin

5 Microcystin Levels in Croke

6 Extremely High Levels of Microcystin Have Been Seen In The Past

7 HAB's Became a Problem Without A Solution Unable to Treat Due to DO Issues Unable to Flush Unable to Bring in Fresh Water Hot and Dry Summer Weather Means No Water Coming In Odor Issues Microcystin Issues Issues with People/Pets Contacting Water Community Becoming Increasingly Upset

8 We've Got To Do SOMETHING About This Lake...

9 Biochar Is A Specially Produced, Highly Absorbent Type of Charcoal Produced By Heating Wood With Little or No Oxygen Under Very Specific Conditions What Is This Biochar?

10 Biochar Has Some Interesting Properties Very Porous Shape of Pores Provide A LOT of Surface Area 1 Gram Contains Approximately 400 Square Meters of Surface Area A Cation Exchange Capacity That Electrostatically Attracts Other Types of Molecules,Including Nitrogen and Phosphorous Nutrients in Both Air and Water Makes Biochar a Great Absorber

11 Biochar Magnified 120x

12 Biochar Magnified 1200x

13 Biochar and BiocharNow Biochar Produced Locally by BiocharNow BiocharNow is Experimenting with Different Sources, Beetle Kill Pine Is Common Source Available in Nylon Socks for Aquatic Use Also Available in Different Sizes of Aggregate for Terrestrial Use-Agriculture and Horticulture BiocharNow Has Done Several Studies On Efficacy of Biochar in Different Applications Including Agriculture, Site Remediation, And Water Quality

14 BiocharNow And Removal of Metals

15 BiocharNow and Removal of Nutrients

16 BiocharNow and Organic Sediment Reduction Can Be Used To Reduce Organic Sediments BiocharNow Can Be Placed Directly on Lake Bottom Placement in Water Column Can Also Reduce Phosphorus in Sediments As Phosphorous is Removed From Water Column, Phosphorous from Sediments will Re-mineralize and Release back into Water Column This is Absorbed by Biochar Socks Over a Relatively Short Period of Time Can Result In Total Reduction of Phosphorous Over Time

17 Biochar and the Fishery BiocharNow Shared a Study Done As Part of a Remediation Project for Mercury Looked at What Happens When Biochar Is Ingested Found That it Passes Through Digestive Tract Without Releasing Anything Also Found That It Can Detoxify Digestive System The Result Was Bigger Fish-Up to 30% Bigger

18 Hmmm...And You Say You Can Use This Biochar In A Lake?

19 Concerns Summarized By Two Basic Questions What Don't We Know About Using It? Will It Even Work?

20 We've Got To Do Something...

21 Let s Take Another Look At The BiocharNow Easy to Deploy Cost Was About the Same as Treatment Probably Wouldn't Cause Further Problems Fast/Easy to Remove if Necessary Nothing to Loose and Everything to Gain

22 Ok...We're Going to Use the BiocharNow...

23 Putting The Plan Together Recommended Placement is About 8 Socks/Surface Acre Croke is 15.5 Surface Acres=124 Socks-Not Comfortable With This... For Socks to Work, Water Must Circulate Through Them Project Design Driven by Lack of Direct Experience Localized Placements With Maximized Blue-Green Algae Contact and Gradual Contact With Lake Water Croke Has A Great Deal of Wind Exposure Blue-Greens Surface and Wind Collects Them in Two Coves on East Side of Lake Over Time, A Lot of Lake Water Gradually Circulates Through Coves

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25 The Plan An Array of 20 Socks in Both Windward Coves Socks of 2 Feet Lengths Placed in Photic Zone With Good Water Surface Contact Socks Placed in Offset Rows of About 40 Feet Apart Maximized Contact With Blu-Greens and Good Chance of Effective Water Contact Over Time Easy to Remove If Problems Occurred Could Leave Installation in Place If Effective Seemed the Best Balance of Upsides Versus Risks and Unknowns

26 Placement of BiocharNow Socks

27 Project Installation Socks Moored With Half Sized Cinder blocks Tied on With Nylon Rope Float Tied to Top of Each Sock to Aid in Flotation and to Mark Placements Signage Posted to Inform Public and Anglers

28 Placement Day

29 It Seems to be Working!!!

30 Field Observations and Data

31 Field Observations Initial Bloom Clear After a Couple Days Blooms Continued to Cycle In and Out Over Remaining Growing Season Intensity of Blooms Significantly Decreased Duration of Blooms Significantly Decreased Many More Bloom Free Days Odor Produced By Blooms Significantly Decreased

32 Total Chla (ug/l) TP (mg/l) The Data Chlorophyll a vs Total Phosphorus /08/ /08/2017 Chla 06/08/ /08/2017 TP (mg/l) 10/08/ /08/ /08/ /08/ /08/ /08/ /08/2018

33 Anecdotal Observations Observed What Appears to be Small Colonies of Microcystus Absent of Green Color Looks Like Small Albino Colored Paint Slicks Appeared As Blooms Subsided, Never Previously Observed in Lake??????? Significantly Reduced Level of Microcystin Compared to June CDPHE Analysis Observed About Two Weeks After Installation Via ABRAXIS Test. Possibly the Biochar, No Data Yet to Support This So Far, No Negative Impact to Fishery Observed

34 Summary Appears To Be Reducing Phosphorous Seems To Be Making The Blue-Greens Disappear Phosphorous and Chlorophyll Measurements Seem to Align With Field Observations

35 Regarding Disappearing Blue-Greens... A Few Modes of Action Have Been Proposed Algae Simply Being Snagged By BiocharNow Socks Upon Contact Algae Being Snagged and Actually Absorbed Algae Being Snagged, Cells Destroyed and Bad Stuff Being Absorbed Bacteria Harbored By Biochar Attacking Algae Some Combination of the Above Don't Know For Sure At This Point...

36 What About the Stuff Absorbed in the Biochar? Studies Show that Stuff Absorbed by Biochar Stays in the Biochar and Doesn't Re-Release Two Things Can Cause Re-Release Very Acidic Water-pH of 4 ½ or Less Will Cause Release Cationic Exchange Properties of Plant Roots Can Tickle Nutrients Free

37 What Do You Do With Used Biochar? Can Be Used As Soil Amendment So Long As It Isn't Being Used To Grow Something That Will Be Eaten Have Seen Studies Showing That Biochar Does Not Release the Bad Stuff Would Like the Opportunity for Further Study... For Example, Is Microcystin Being Abosrbed? Can We Find Out From Used Biochar? If So, What Happens To It Over Time? Does it Break Down Within The Biochar?

38 The Engineering Didn't Work Biochar Socks Provided Positive Results, Our Installation Engineering Didn't After About 6 Weeks Our Socks Started Sinking Buoys Not Robust Enough To Keep Things Floating Planning to Try Pontoons Constructed with 6 inch PVC Pipe Looking for Other Ideas...

39 Our Next Steps Will Leave Sunken Socks In Place Will Add New Arrays Into Coves, Would Like To Begin Growing Season With Fresh Biochar Biochar Placements Around Storm Water Inlets At Croke Investigating Integration of BiocharNow Socks with LG Sonic Industrial Wet Ultrasonic Algae Suppression System Considering BiocharNow Placement in Webster Lake for Controlling HAB's and Reducing Potential Microcystin Levels Will Likely Experiment Loose Granular Spot Treatments on Water Surface

40 In Closing... Really Does Seem To Be Working But...We've Only Really Had A Few Months of Hands-On Experience With It Would Like To See A Full Year With A Full Management Season of Data and Field Observations and Some Additional Study We Were Really In The Position To Break New Ground And Try Something New and Outside Box. So Far, We're Seeing Some Real Potential Here Found Be A Flexible To Work With and Readily and Cheaply Obtainable Locally Properties of Biochar Are Known And Studied. Room for Some Imagination and Study In Potentially Developing and Integrating a New Tool When the Textbook Just Isn't Working No Such Thing As A Magic Solution...At the Least, Our Experiment Has Shown Some Measurable Progress In Meeting A Difficult Management Issue

41 Contact Information BiocharNow: James Gaspard Chief Executive Officer, BiocharNow Cell: