In-Situ Groundwater Nitrification and De-Nitrification Remediation Processes

Presented by Steve Mailath, EBA Engineering Consultants

Ltd.Phone: 403.723.6898

Problems with Ammonia and Nitrate

• Over fertilization (eutrophication) of surface waters with N

• Ammonia toxic to animal species – fish and invertebrates

• Nitrate contamination of drinking water– blue baby syndrome – methemoglobinemia

• Discounted value of brown-field development

Environmental and Regulatory Issues

• Environmental regulations are becoming more stringent with time– Environmental enforcement orders

• Growing public concern of environmental management

• Restricted land use

Where is the Problem – Who is responsible

• Fertilizer manufacturing and storage facilities– Brown-field developer

• Sewage treatment facilities– City of Calgary

• Agricultural areas– Farmers

• Airports– Calgary airport authority

Problems with Existing Solutions

• Expense– Treatment facilities– Piping– Operating

• Large footprint, need to close site

In-Situ Groundwater Nitrification andDe-Nitrification Remediation Processes

In-situ nitrification:• Extracting groundwater• Adding oxygen and nutrients• Injection of amended groundwater

In-situ de-nitrification• Extracting groundwater• Adding carbon and nutrients• Injection of amended groundwater

By: Steve Mailath, EBA Engineering Consultants Ltd.Patent Pending: David Reese, University Technologies International, Phone: 270.2434

Dr. Angus Chu, U of C, Phone: 220.8987Steve Mailath, EBA, Phone: 723.6898

Advantages

• Performs as well as best in class solutions at less than half the cost

• Full mass removal - nitrates reduced to N gas• Small footprint and less intrusive than most

solutions• Requires fewer wells and piping• Year round treatment• Free bio-reactor (in situ)

Options

Options Main Limitations Capital($ Million)

Operating

($/year)

Present Value Cost1

($ million)1. Groundwater Extraction and Irrigation Summer

treatment$0.85 $57,000 $1.4

2. Groundwater Extraction and Discharge to City Sanitary Sewer

Removal of ammonia only

$0.69 $50,000 $1.2

3. Groundwater Extraction and Electrochemical Treatment

High cost $3.1 $155,000 $4.7

4. Groundwater Extraction and Biological Treatment (Nitrification)

High cost $1.6 $100,000 $2.6

5. Groundwater Extraction and Wetlands Disposal

Summer treatment, low N

$0.64 $51,000 $1.2

6. In-Situ Electrochemical Treatment Low perm soils $2.8 >$35,000 >$3.0

7. On-Site Ex-Situ Biological Treatment High cost $5.0 to $7.0

>$35,000 >$5.0

8. In-Situ Nitrification and High perm soils $0.2 $30,000 $0.5

De-Nitrification $0.1 $25,600 $0.41 Present value based upon 15 year life and 5% rate of return.

Nitrate Plume

Ammonia Plume

Site Plot Plan

Cross-Section A-A’

Cross-Section D-D’

Typical Gravel

Hydraulic Parameters

• Section length 425 m (perpendicular to flow • Section thickness 3.0 m• Hydraulic conductivity 49 m/day• Hydraulic gradient 0.0023• Groundwater velocity 0.3 – 0.5 m/day• Groundwater flux 144 m3/day (22 igpm)• Ammonia concentration 63.2 mg-N/L• Nitrate concentration 94 mg-N/L (i.e., 31 mg-N/L

in-situ plus 63 mg-N/L generatedby nitrification)

In-Situ Nitrification

Pilot Test Site

Test Site

GROUNDWATER FLOW

Test Site

INJECTIONWELL

EXTRACTION WELL

Installing Monitoring Wells

Test Site

TREATMENT SHED

Nitrification

TREATMENT SHED

Oxygen Addition

OXYGEN SOURCE

Amendment Addition

GAS LIQUID REACTOR

NUTRIENT DELIVERY

OXYGEN DELIVERY

Amendment Addition

VENTURI

Nitrification Results

0.00

20.00

40.00

60.00

80.00

100.00

120.00

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93 97 101

105

109

113

117

121

125

129

133

137

141

145

149

Days

DO

, Am

mon

ia,

Nitr

ate

- N C

once

ntra

tion

(mg/

L)

0.00

0.20

0.40

0.60

0.80

1.00

1.20

Phos

phat

e - P

Con

cent

ratio

n (m

g/L)

TH13 NH4TH13 NO3TH13 DOTH13 PO44 per. Mov. Avg. (TH13 NH4)4 per. Mov. Avg. (TH13 NO3)4 per. Mov. Avg. (TH13 DO)

66 – 89 % AMMONIA REDUCTION

In-Situ De-Nitrification

Pilot Test Site

Amendment Addition

NUTRIENT DELIVERY

NO OXYGEN DELIVERY

De-Nitrification

NUTRIENT DELIVERY CARBON

DELIVERY

Field Lab

De-Nitrification Results

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Days

DO

, A

mm

onia

, Nitr

ate

- N C

once

ntra

tion

(mg/

L)

4 per. Mov. Avg. (TH1 DO)4 per. Mov. Avg. (TH1 NH4)4 per. Mov. Avg. (TH1 NO3)

Nitrate

Ammonia

Dissolved oxygen

78 – 99 % NITRATE REDUCTION

Options

Options Main Limitations Capital($ Million)

Operating($/year)

Present Value Cost1

($ million)1. Groundwater Extraction and Irrigation Summer treatment $0.85 $57,000 $1.4

2. Groundwater Extraction and Discharge to City Sanitary Sewer

Removal of ammonia only

$0.69 $50,000 $1.2

3. Groundwater Extraction and Electrochemical Treatment

High cost $3.1 $155,000 $4.7

4. Groundwater Extraction and Biological Treatment (Nitrification)

High cost $1.6 $100,000 $2.6

5. Groundwater Extraction and Wetlands Disposal

Summer treatment, low N

$0.64 $51,000 $1.2

6. In-Situ Electrochemical Treatment Low perm soils $2.8 >$35,000 >$3.0

7. On-Site Ex-Situ Biological Treatment High cost $5.0 to $7.0 >$35,000 >$5.0

8. In-Situ Nitrification and High perm soils $0.2 $30,000 $0.5

De-Nitrification $0.1 $25,600 $0.41 Present value based upon 15 year life and 5% rate of return.

Questions

In-Situ Groundwater Nitrification andDe-Nitrification Remediation Processes

By: Steve Mailath, EBA Engineering Consultants Ltd.Patent Pending: David Reese, University Technologies International,

Phone: 270.2434Dr. Angus Chu, U of C, Phone: 220.8987Steve Mailath, EBA, Phone: 723.6898

QUESTIONS