Lake Jessamine Lake Jessamine Sediment Inactivation Project Final - - PowerPoint PPT Presentation

Lake Jessamine Lake Jessamine Sediment Inactivation Project

Final Results

June 5 2014 June 5, 2014

Harvey H. Harper, Ph.D.,P.E.

Melissa Lavigne

NE Lobe

General General Overview

• f Lake

J i

Central Lobe East Lobe

Jessamine

SW Lobe South South Lobe

Probing Locations for Water and Muck Depths in Lake Jessamine (March 29, 2011) ( , )

Water Depth Contours Water Depth Contours (ft) for Lake Jessamine

• n March 29, 2011

Muck Depth Contours Muck Depth Contours (ft) in Lake Jessamine

• n March 29, 2011

l - a (mg/m3) 30 40 50 60 Middle Northeast Southwest

Trends in Chlorophyll-a Concentrations in Lake

Year Chlorophyl 10 20 60

Middle

Jessamine from 2000-2013

Year Chlorophyll - a (mg/m3) 20 30 40 50

p = <0.0001 slope = 0.4861

Middle

• chlorophyll-a is a

photosynthetic pigment

Year C 10 mg/m3) 40 50 60

p = 0.5683 slope = -0.0682

Northeast Lobe

• indicator of algal biomass

Chlorophyll - a (m 10 20 30 Year

• phyll - a (mg/m3)

30 40 50 60

p = 0.0071 slope = 0.5063

Southwest Lobe

Year 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 Chloro 10 20

Lake Trophic State Classifications

Oligotrophic Lake

• Low in nutrients
• Few algae grow

N l l bl

• No algal blooms
• Water is very clear
• Support very few plants and fish
• About 12% of Florida lakes

W t l it 12 f t

M t hi L k

• Water clarity > 12 feet
• Chlorophyll < 3 micrograms/liter
• Total P < 15 micrograms/liter

Float

Mesotrophic Lake

• Moderate in nutrients
• Moderate algal production
• Periodic algal blooms

Seepage Meter Float

• Slightly green water
• Support moderate amounts of plants and fish
• About 31% of Florida lakes
• Water clarity 8 – 12 feet
• Chlorophyll 3 - 7 micrograms/liter
• Total P 15 to 25 micrograms/liter

Lake Trophic State Classifications – cont.

Eutrophic Lake

• High in nutrients
• High level of algal production

g g p

• Frequent algal blooms
• Green water with poor visibility
• May have large amount of plants
• About 41% of Florida lakes

H t hi L k

• Water clarity 3 - 8 feet
• Chlorophyll 7 to 40 micrograms/liter
• Total P 25 to 100 micrograms/liter

Hyper-eutrophic Lake

• Very high in nutrients
• Extremely high algal production
• Virtually constant algal blooms

y g

• Most biologically productive lakes
• Support large amounts of plants and fish
• About 16% of Florida lakes
• Water clarity < 3 feet

y

• Chlorophyll > 40 micrograms/liter
• Total P > 100 micrograms/liter

TSI 40 50 60 70 80

Mesotrophic Eutrophic Hypereutrophic

Trends in TSI Values in Lake Jessamine

T 10 20 30 Middle Northeast Southwest 80

Middle

Oligotrophic Hypereutrophic

in Lake Jessamine from 2000-2013

TSI 20 40 60

p = 0.0001 slope = 0.7227

Middle

Oligotrophic Mesotrophic Eutrophic

60 80

Northeast Lobe

Mesotrophic Eutrophic Hypereutrophic

TSI 20 40

p = 0.0048 slope = -0.3644 Oligotrophic

TSI 40 60 80

p = 0 0043

Southwest Lobe

Mesotrophic Eutrophic Hypereutrophic

Year 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 20

p = 0.0043 slope = 0.7917 Oligotrophic

Mean Monthly Concentrations of Total Ph h i L k J i f 1989 2009 Phosphorus in Lake Jessamine from 1989-2009

Dry Season Dry Season Rainy Season

H d l i B d t C t Hydrologic Budget Components

Precipitation Evaporation Interconnected Lake Inflows ec p tat o p Runoff

± ∆ Storage

Outflow Groundwater Seepage Deep Recharge

Summary of Mean y Annual Hydrologic Inputs and Losses to Lake Jessamine Lake Jessamine

Nutrient Budget Components Nutrient Budget Components

Bulk Precipitation Precipitation Interconnected Lake Inflow Runoff Outflow Sedimentation Internal Recycling Groundwater Seepage Deep Deep Groundwater

S f M Summary of Mean Annual Mass Inputs and Losses of Total Phosphorus to Lake Jessamine

• Lake Jessamine is a P limited lake
• P inputs must be controlled to

improve water quality

Locations of Sediment Locations of Sediment Monitoring Sites in Lake Jessamine

Photographs of Typical Sandy Sediments Collected in Lake Jessamine During December 2010

Photographs of Typical Sandy and Organic Muck Sediments Collected in Lake Jessamine During December 2010

Typical Zonation in a Lake

Pelagic Zone (Open water) Littoral Zone Littoral Zone Zone Zone

Epilimnion

• Photic zone

~1% of surface light Photosynthesis > Respiration

Hypolimnion

• Poor circulation
• Anoxic

g Respiration > Photosynthesis

Lakes are sinks for nutrients

• Organic matter accumulates in the bottom of lakes and undergoes decomposition

18 18

Organic matter accumulates in the bottom of lakes and undergoes decomposition – Nutrients are released during the decomposition

Phosphorus Bonding in Sediments

P i l k di t i ll b d i i ti ith P in lake sediments is generally bound in associations with:

– Saloid

Consists of soluble P in pore water and easily exchangeable P

I d – Iron and manganese

Direct inorganic precipitates (ex. FePO4) and adsorption onto Fe/Mn oxides Stability depends on redox potential

– Bond with P is strong under oxidized conditions g – Bond breaks apart under reduced conditions

– Calcium

Primarily as inorganic precipitates B i ifi t t hi h H Becomes more significant at higher pH Stability depends on pH

– Aluminum

Direct inorganic precipitates (ex AlPO4) and adsorption onto metal oxides Direct inorganic precipitates (ex. AlPO4) and adsorption onto metal oxides Stability depends on pH

– Organic matter

Fresh matter – decomposes relatively quickly p y q y Recalcitrant matter – decomposes very slowly

Significance depends on geology of the watershed and lake

19 19

P Fractionation of Sediments

Saloid

l bl il h bl P

• Available for

release

Saloid – soluble + easily exchangeable P Fe Bound – sediment P bound with Fe

release

• Σ(Saloid + Fe

Bound) is referred to as “Total available P”

Al Bound

sediment P bound with Al

available P

Al Bound – sediment P bound with Al Ca Bound – sediment P bound with Ca Organic Bound

P i t d ith

Unavailable for release

Organic Bound – P associated with

• rganic matter

Inactivant Dose Determination

Based on available P in sediments The 0 10 cm layer of the sediments is

Generally considered to be the extent of

The 0-10 cm layer of the sediments is sectioned off and speciated for available P using a modification of the Chang and Jackson technique

10 cm

be the extent of P diffusion from sediments

Sufficient inactivant is added to bind all available P in the top 10 cm

Thick flocculent organic sediments

10 cm

Alum dose determined by:

Alum dose = total available P x Al:P ratio Thick, flocculent, organic sediments El t Electronegativity

Al:P ratio usually between 5-10

Element g y (Pauling Scale) Fe 1.8 Al 1.6 Ca 1 3 Ca 1.3 La 1.1

Modified Chang and Jackson Speciation Procedure for Evaluating Sediment P Bonding

Wet

2N NH4Cl (30 minutes)

Saloid-Bound

Procedure for Evaluating Sediment P Bonding

Wet Sediment

4

( )

Saloid Bound Phosphorus

Potentially available

Residue

0.5 N NH4F (1 hour)

Aluminum- Bound Residue Bound Phosphorus

Unavailable

Residue

0.1 N NaOH (17 hours)

Iron-Bound Residue Phosphorus

Potentially available

Isopleths of Total Available Phosphorus Phosphorus in the Top 10 cm of Sediments in Lake Jessamine

• sum of saloid + iron bound P

Internal Recycling = 139 kg total P/yr = 43% of total inputs Groundwater Seepage = 36 kg total P/yr = 10% of total inputs Combined inputs = 49%

Application Map Indicating the Fraction of Total Alum the Fraction of Total Alum to be Applied to the Identified Zones

Applied Chemical Quantities for Lake Jessamine Sediment Inactivation Lake Jessamine Sediment Inactivation

Sodium Gallons per Application Zone Fraction

• f Total

Alum (gallons) Sodium Aluminate (gallons) Gallons per Application Alum Sodium Aluminate 1 0.24 45,027 11,436 15,009 3,812 2 0.48 91,280 23,182 30,427 7,727 3 0.22 41,545 10,551 13,848 3,517 4 0.04 6,993 1,776 2,331 592 , , , 5 0.02 4,155 1,055 1,385 352 TOTAL: 189 000 48 000 63 000 16 000 TOTAL: 189,000 48,000 63,000 16,000

Application Boat and Tanker Barge Used for Al A li ti i Alum Application in Lake Jessamine

itrogen (µg/l)

1500 2000 2500 3000

Middle Northeast Southwest

ERD Middle ERD Northeast ERD Southwest

Comparison of Pre

3000

Total Ni

500 1000

Middle

ent ent ent

Comparison of Pre- and Post-Treatment Concentrations of Total

Total Nitrogen (µg/l)

500 1000 1500 2000 2500 Alum Treatme Alum Treatme Alum Treatme

Nitrogen in Lake Jessamine

Year 500

n (µg/l)

2000 2500 3000

Northeast Lobe

Total Nitrogen

500 1000 1500 Year

Nitrogen (µg/l)

1500 2000 2500 3000

Southwest Lobe

Year

08 09 10 11 12 13 14

Total

500 1000

phorus (µg/l)

20 30 40 Middle Northeast Southwest ERD Middle ERD Northeast ERD Southwest

Comparison of Pre- d P t T t t

Year

Total Phos

10 80

Middle

ent ent ent

and Post-Treatment Concentrations of Total Phosphorus in Lake

• tal Phosphorus (µg/l)

20 40 60

Middle

Alum Treatme Alum Treatme Alum Treatme

p Jessamine

Year

To us (µg/l)

60 80

Northeast Lobe

Total Phosphoru

20 40 Year

Phosphorus (µg/l)

15 20 25 30 35

Southwest Lobe

Year

08 09 10 11 12 13 14

Total P

5 10

Secchi Disk

Secchi Disk

– The depth at which a 20 cm disk can be viewed viewed

A measure of water column transparency An estimate of algal biomass in the water Depth of the photic zone

Standard 20 cm Disk

Father Pietro Secchi

Scientific advisor to the Pope Scientific advisor to the Pope (1818-1878)

Depth (m)

1 2 Year

Secchi D

3 4 5 Middle Northeast Southwest ERD Middle ERD Northeast ERD Southwest

Comparison of Pre- and Post-Treatment Secchi Disk Depths in Lake

Year

Secchi Depth (m)

1 2 3 4

Middle

Treatment Treatment Treatment

Disk Depths in Lake Jessamine

Year 4 5

h (m)

1

Northeast Lobe

Alum Alum Alum

Secchi Depth

2 3 4 5 Year

cchi Depth (m)

1 2 3

Southwest Lobe

Year

08 09 10 11 12 13 14

Sec

4 5

Summary of Mean General Characteristics of Pre- and Post-Treatment Sediment Core Samples Collected in Lake Jessamine During December 2010 and September 2013

Parameter Units Mean Value By Sediment Collection Date1 December September December 2010 September 2013 pH s.u. 6.41 6.21 Moisture Content % 51 2 50 8 Moisture Content % 51.2 50.8 Organic Content % 5.4 5.6 Density (wet) g/cm3 1.57 1.58

3

Total Nitrogen g/cm3 1,653 1,522 Total Phosphorus g/cm3 119 111

• 1. Reflects geometric mean values

Statistical Summary of Pre- and Post-Treatment V l f H d M i t C t t i th T Values of pH, and Moisture Content in the Top 10 cm of Lake Jessamine Sediments

H M i t C t t pH

7 0 7.5

Moisture Content

100 6.5 7.0

ntent (%)

60 80

pH

5.5 6.0

Moisture Con

40

Outlier 90

th Percentile

4.5 5.0

M

20

75

th Percentile

Median 25

th Percentile

10

th Percentile

Mean

Pre Post Pre Post

Statistical Summary of Pre- and Post-Treatment V l f O i C t t d W t D it i th T Values of Organic Content and Wet Density in the Top 10 cm of Lake Jessamine Sediments

O i C t t W t D it Organic Content

60 70

Wet Density

2.5

tent (%)

40 50 60

(g/cm3)

1.5 2.0

Organic Con

20 30 40

Wet Density

1.0

O

10

W

0.0 0.5 Pre Post Pre Post

Statistical Summary of Pre- and Post-Treatment V l f T t l Nit d T t l Ph h i th T Values of Total Nitrogen and Total Phosphorus in the Top 10 cm of Lake Jessamine Sediments

T t l N T t l P Total N

5000 6000

Total P

300 350

Outlier 90

th Percentile

75

th Percentile

M di

g/cm3)

4000 5000

g/cm3)

200 250

Median 25

th Percentile

10

th Percentile

Mean

Total N (µ

2000 3000

Total P (µ

100 150 e t 1000 e t 50 Pre Post Pre Post

Saloid Bound

6 7

Iron Bound

200

Outlier 90

75

Median

Statistical

Bound P (µg/cm3)

3 4 5

• und P (µg/cm3)

100 150

Median 25

10

Mean

Statistical Summary of Pre- and Post- T t t V l

Saloid B

1 2

Iron Bo

50

Treatment Values

• f Sediment

Phosphorus

Pre Post Pre Post

Aluminum Bound Total Available P

p Speciation in Lake Jessamine Sediments

g/cm3)

140 160 180 200

µg/cm3)

150 200

Sediments

Aluminum P (µg

40 60 80 100 120

• tal Available P (

50 100 Pre Post 20 40 Pre Post

T

Summary of Mean Pre- and Post-Treatment Ph h S i ti i S di t C S l Phosphorus Speciation in Sediment Core Samples Collected in Lake Jessamine

Parameter Units Mean Value by Sediment Collection Date1 Change in Concentration Parameter Units Collection Date1 Concentration (%) Pre- (12/10) Post- (9/13) S l id B d P /

3

0 41 0 05 89 Saloid-Bound P g/cm3 0.41 0.05

• 89

Fe-Bound P g/cm3 49 7

• 86

Total Available P g/cm3 50 7

• 86

% of Total Sediment P % 42 6

• 85

Al-Bound P g/cm3 31 53 74

• 1. Reflects geometric mean values

Mean Monthly Concentrations of Total Phosphorus in Lake Jessamine from 1989-2009 Phosphorus in Lake Jessamine from 1989 2009

The alum treatment will reduce P concentrations the most during dry season conditions

Summary

Lake Jessamine is a phosphorus limited lake

– Largest P loading is contributed by internal recycling (43% of – Largest P loading is contributed by internal recycling (43% of total)

Sediment inactivation conducted in Lake Jessamine in 3 t li ti separate applications

– 189,000 gallons of alum – 48,000 gallons of sodium aluminate g

Treatment was successful in reducing available P in Lake Jessamine while increasing unavailable P bonding

A il bl P d d b 86% – Available P reduced by 86% – Aluminum bound P increased by 74%

Questions?