Transport Canada TransportsCanada 

## 1+1 N,* A4roports



## Safety and Sbcuritt! Technical et services Services techniques

A COMPARISON OF THE EFFECTS OF UREA, POTASSIUM ACETATE, CALCIUM MAGNESIUM ACETATE AND SODIUM FORMATE RUNWAY DE-ICERS ON THE ENVIRONMENT

### A COMPARISON OF THE EFFECTS OF UREA, POTASSIUM ACETATE, CALCIUM MAGNESIUM ACETATE AND SODIUM FORMATE RUNWAY DE-ICERS ON THE ENVIRONMENT

Transport Canada Service de I'environnement et de soutien Airports SBcuritB et services techniques Safety and Technical Services ABroports Environmental and Support Services Transports Canada- GROUP

October 26,1994 

### Mr. Alee Simpson Transport Canada EnvironmentalReview Services Place de Vilk Ottawa, Ontario 

### KIA ON8 AD1 Nolan Davis Inc. 7020 Mamfotd Road, Hallfax, NS, Canada B3L IS9 Ttl: (902) 453-5555 Fax: (902) 453-6325

File 

### No. 21-0059-154-1

Jd Dear Mr. Si son: /



# kt*. Re: Envimnrnentd Impsct of 

### Runwav De-Seers We are pleased to submit five copies of 

### a 

### summary report of the results of the three evaluations of new runway de-iccrs that AD1Nolan Davis has undertaken for 

### Transport Canada,namely,potassium acetate,calciummagnesium acetateand sodiumfonnate, against urea. This report summarizes the key information and recommendations. Details on the studies are contained in the three full reports on 

### which this summary report 

### k based. We would like to thank you and your associates for the cooperation generously offered throughout the project. Yours very truly, AD1 Nolan Davis Inc



### Roy D. John, BSc Chief Environmental Chemist

Engineering, Consulting. Procurementand Project Management H.Iff.x, Sydney, St. Jobr 'r, FrederlctoaTABLE OF CONTENTS Page 

### No.

1.0 INTRODUCIION 

# ............................................. 1 1.1 Backntound 

# .............................................. 2 1.2 Study Site 

# .............................................. 3 13 Refemnces 

# .............................................. 7



# ............... ............................ 2.0 ICmODOmGY 0. 7 2.1 Collection and Assessment of Existing Data 

# ..................... 7



# ............................ 2.2 Reconnaissance'and Site Selection 7 23 Design of the Field Promm 

# ............................ 

# .... 8 23.1 Soils Sampling and Testing Program 

# .................... 10 23.2 Surface Water Monitoring Program 

# ..................... 10 233 Groundwater Monitoring Program 

# ..................... 11 23.4 Soil Water Monitoring Progrsms 

# ....................... 12 235 Climatological Data 

# ................................ 12 2.4 Bioloaical Field Samplinn Procedures 

# ........................ 13 2.4.1 Artificial Substrates 

# ................................ 13 2.4.2 Soil Microbiology and Surface Vegetation 

# ................. 13 2.43 SurfaceVegetation 

# ................................. 14 2.4.4 QualityAssurance 

# ................................... 14 2.5 In-house Laboratow Exmriments 

# ........................... 15 3.0 COMPARISON OF THE PERFORMANCE OF UREA, KA, 

### CMA AND NaFo 

# ...................................................... 15 3.1 Site Designation 

# ........................................ 15

. 3.2 Backemund 

# ............................................ 15 3.2.1 iheAcid Drainage Problem 

# .......................... 16 3.2 SOdiumLevels 

# .................................... 18 33 Impact of De-icer Chemicals 

# ............................... 18 33.1 Urn 

# ............................................ 18



# .................... 33.2 CMA (Calcium Magnesium Acetate) 19 333 NaFo (Sodium Formate) 

# ............................. 30 33.4 

### KA 

# ............................................. 32

.



# ...................... 4.0 CONCLUSIONS AND RECOhfMENDATIONS 40



# ............................................ 4.1 Conclusions 40 4.2 Recommendations 

# ....................................... 40Comparison Repon Runway De-ictts l'nnsport Canada Page i



### AD1 Nolan Davis 

### hc.was contracted by Transport ha&to evaluate the environmental impact of threemy de-iccrs, potassium acetate, calciummagnesium acetate and 

### sodium formate at the Halifax International Airport between 1990and 1994, A test program was devised whereby each de-iwwas field tested and compared to urea, thede-icerin currentuse. Samplesofshct andgroundwaterwere dectedroutinely and at intends during stom events, when de-icer was being applied. 

### The aquatic biology of nearby strmwas investigated and a laboratory evaluation of the impact on surface vegetation, fungi and soil respiration rate was done. Theresults showed each of the new de-icestobe relatively benign and to haveless impact 

### on the 

### environment than urea.

AD1 Nolan Davis lac 214059-1561Comparison Report Runway De-iccrs Transport Canada Page 1



### This report is a summary of the studies which were undertaken 

### to evaluate the environmental impact of three chemicalde-icersproposed for use on airport runways. The studies include a the results ofliterature, field and laboratory investigations undertaken to establish the environmental impact of potassium acetate, sodium formate and dcium magnesium acetate as comparedto ur& For operational considerations it is necessary to contactthe Director, Engineering and Maintenance of Transport Canada's Airport's Group in Ottawa. To illustrate the results, only selected data 

### has been used in this summary report. Fult detaii of the environmental research programs can be found in the contract reports "Environmental impact from the use of potassium acetate at Halifax International

### Airport," (AD1Nolan Davis 19941, "Environmental impactftomthe use of sodiumformate at Halifax International Airport," (Nolan, Davis 1992) and "Environmental impact from the use of calcium magnesium acetate at Halifax International Airport," (Nolan, Davis 1991). 

### Every winter, major airports in the northern hemisphere are confronted with snow and fieezing rain conditions, which play havoc with airline schedules and compromise human safety. Strivingto maintain safe conditions forthe travellingpublic duringthewintermonths poses operating problems for airlines and airport operators. To overcome these problems, airport operators apply cheraicals to aircraft, taxiway and runway surfaw. The chemicals are selectedfor their abilityto prevent the formationof ice on aircraft and runways (anti-icing), or to melt ice and snow when formation has occurred (de-icing). There is, however, a down side to the beneficial use of these chemicals. World wide environmental awarenesshas focusedattentionupon thedamagethey impose upon the

---- en!!rommtc

- - - - - - - - - - - - - - - - -

------ - - - - The chemicalcommonly used at Canadian airportson runways is urca The decayproducts of urea are nitrate, nitrite and ammonia Elevated ammonia concentrationscan be tclxic to faeshwater organisms while the nitrates, 

### in addition to promoting algal blmms, psc potential human health poblenrs 'Phe toxicity 

### aspect of urea has rcsdtd in its ban at 

### airports in several countries. The United States Environmental Protection Agency introduced tough regulatiom for storm water discharges which are aimed at regulating deicing fluid discharges.Comparison Report Runway Deicers Transport Canada Page 2

The problems associated with the use of 

### urea, have given rise to the development of low toxicity alternatives. Threesuch products arecalciummagnesium acetate,potassium acetate and sodium formate. Calcium magnesium acetate (CMA) and sodium fonnate (NaFo) are applied in solidformwhile potassium acetate (KA) is sprayed in liquid form on my and runway surfaces. Transport Canada decided to conduct a field test of 

### KA,CMA and NaFo at an airport site which was considered to be representative of most Canadian airports, Accordingly, AD1 Nolan Davis Inc. was contractedto assessthe environmentalimpact of

### KA,CMA and NaFo versus urea at Halifax International Airport. The field tests also sought information concerningthe operational capabilities of 

### K& CMA and NaFo versus urea.
Canada pioneered the use of granular urea as an anti-icing and de-icing materialfor airport runways on a large scale and it was adopted as the standard de-icing agent for runways and taxiways at Canadian airports about three decades ago. Urea was selected becaw it did not corrode aircraft parts (including aluminum),stain paints, or affect the plastic of 

### aircraft windows. Urea, generally made up of at least 46% nitrogen, will melt ice at temperatures of minus 1$~ or higher. Environmental concern about the use of urea at Canadian airports began in British Columbiain 1971and attentioncentred aroundpossibleeutrophicationofdownstreamlakes, as proliferation ofneeds in the Okanagan lakes was already a concern. Studies at Penticton Airport found that applications ofurea were roughlyfourtimes the normal agn'culturalrate. It 

### was also noted that grass along runways grew better due to the nitrogen input from the urea. Studiesat Kelowna Airport confirmed that,thenitrogen contentof snowadjacentto runways was highest near the runway and decreased considerably beyond about 30 

### m ffom the runway. Analysis of surface runoff 

### from the Toronto Airport betyeen 1974 and 1977 indicated that asmuch as 64percent ofth&d ureainitrogen appliqdentered surface water

Y, N~O& -... ... , , *, 

### . I, . .. .-a , r i , ..*.
.I L .. -.

. c-I . '*.S ** .I

### . 2, 1- ...... ...-..... Concern about glycol based de-iccrs is primarily assddiatd with their ~cePtiohy high oxygen demand. While the direct toxicity of glycol based de-icers to Guatic organisms is low, the potential reduction in dissolved oxygen in receiving waters could kill or stress organisms, particularly salmonoid fishes.

AD1 Nolan Davis Inc 21 -0059-154-1Comparison Report Runway De-iotn Transport Canada Page 3

Before any alternative can be considered for use 

### as a de-icer, two operational criteriamust be met 

### Tbematerial cannotbe hazardous to the maintenance crew handling it 

### inbulk at the airport. Also it must effectively work as a de-icer and meet the skid requirements of Transport Canada. 

### KA, CMA and NaFo met the above criteria and laboratory data indicate they could substitute for urea (Fig. 1-1). It was then decided to research the environmental impact of the materials under field conditions, the focus of this executive summary report. 13 Study Site 

### In 1960, the federal government opened Halifax International Airport, located about 35 kilometres north-northeast of Halifax and Dartmouth (Figure 1-2). Halifax International Airport (HLA) provides senicesto centres in Nova Scotia, New Brunswick, Prince Edward Island, Newfoundland, Quebecand Ontario and to destinationsin Canada,theUnited States and Europe. HIA straddles a physiographic divide separating the Atlantic 

### Ocean and Bay of Fundy drainage systems. It liesin anundulating plain, which rises graduallyfiom theAtlantic Coast to an altitude of about 153metres at the northern boundary. The topographic expression wer the airport property is variable and is generally bedrock controlled. Topographic elevations over the site vary from 

### 85 metres to 151metres above mean sea level 

### (AMSL) (MacDougall et al, 1963). 

### The portions of the 

### KA, CMA, NaFo and urea study areas which were located 

### within the airport boundaries were generally unforested, whereas the monitoring and sampling areas located outsidethe airportboundarieswere generallyforested,mostly with softwoodspecies. Figure 13 shows the general layout of the airport study area with the sampling locations marked. On the northeast side of the line dividing line running between tieTaxiwayDelta and'Runway 15-33 (the urea study area) the water drains to the Atlantic Ocean. On the south west side of the line (the KA/NaFo/CMA study area) the water also 

### drains 

### to the Atlantic Ocean, but by a separatewatershed.. 

### h addition there are underd..tains on either. side of this linewhich conductsgroundwater away fiom the centre of the taxiway

# - ~~nway. This means that the two study areas are close enough together to receive identicalweather and it was hoped that possibility of cross contamination was not significant By using the experimental de-icers on the taxiwaywhile retaining the proven urea on the runway proper there was 

### no loss 

### iA cafifidczmby tkpkts.

- -- - -- - -

## CONCENTRATION, 

## WT. % 0 10 15 20 25 50 35 45 S(



### LEGEND

---0- UREA 

# - CMA DEICER 

## ; .: ; .

-I---' NUCI -, . : ' '

4 . .,;: 

# --

# ---- --- SOOIUM F DRMAlE

# ,

. .__ I ...... -,

9 .'L 2. . -

A 

### AD1 Nolan Davis 

### Jnc. 

# 4#?9 Enzineering and Environmental Management Halifax, Nova Scotia -- -.- ..-. 

## _ . . -- ". fl(;URE. -1-1-

......... FREEZING POINT DEPRESSION, OF' SIX. RUNWAY DFJCERSI fi

OC~AN

MIBS 30 0 30 60

I
A 

### AD1 Nolan Davis 

### Inc. 

# &s;?g Engineering and Environmental Management Halifax, Nova Scotia FIGURE 1-2 NOVA SCOTU

2tECEND:T-4ASURFACEWATERMONITORINGSTATIONTTESTDE-1CERSTUDYAREAuUREASTUDYAREA----STUDYBOUNDARYB-1BlOLOClCALSAMPLINGSTATIONn-1MONITORINGWELLL-10SOILWATERSAMPUNCSTATIONAAD1NolanDavisInc.brs.R9Bngin*e*ngandEnvironmentalManagementHalifax,NovaSootlaFIGURE1-3MONITORINGSTATIONSTESTDE-1CERandUREAmDYAREASHAUFAXINTERNATIONALAIRPORTComparison Report Runway De-ictrs Transport Canada Page 7

13 References A substantial number of references were used in the Kq. CMA and NaFo studies. 

### AU of these are included in the reference section of this report For the sake of clarity only the key references have been noted in this summaryreport

Each of the studies were divided into three progressive phases of investigation. The first phase was the analysis of existing data, preliminary site reconnaissance and the design of field programs. The second phase encompsrssd field data collection and laboratory analyses. The third phase was the final compilation and interpretation of the data, development of the computerized database, and reporting. 2.1 Collection and Assessment of Existing Data 

### AU availableinformationonthe site, and on the use and environmental impactof

### KA,CMA and NaFowascollected and reviewed. (Sypher:Mueller 1989, and 1986,Elliot, 1987,Homer 1988,Lumis et a1 1991and McAUister 1981) Published and unpublished maps and reports on geology, hydrology, and hydrogeology were considered in the final design of the field program. 2.2 Reconnaissance and Site Selection Once all of the available data were assessed, a site visit was undertaken to identify the KA/CMA/NaFo, urea, and control study areas, and to plan the soil, surface water, soil water and groundwater monitoring proams. During this initial field visit, detailed obsenmtions 

### on geologic, hy&ogeologk 

### mi!, terra.aaeqand surface drainage conditions were recorded and used inidentifying the specificlocations for the groundwater monitoring wells, soil water lysimeters and surface water monitoring stations. Based upon this site reconnaissance it was decided that the K#UChfJb+NzrF~ study area would be located at Taxiway Delta and the mea study ares lwatcd tit the adjacent Runway 15-33 (Figure 1-3). Itwas anticipatedthat se~:uriv 

### a?ld ~perationd (access) restrictions would be less

### withinthe selected area, because Runway 15-33was a secondary xunway to Runway 

### &24,Comparison Report Runway De-ictrs Transport Canada Page 8

For the control study area, a small subwatenhed system, which is a tributary to Johnson River, was selected (Figure 2-1). The headwater reaches of this brook originate in a low lying wetlands area within the forested, southwestquadrant of the airport property. It was considered unlikely that this area has been influencedby the use of de-icers at the airport. 

### An additional advantage was the presence of existing baseline data for the brook. 

### 23 Design of the Field Program The field program was designed to include the following: 1) monitor meteorological conditions; 2) characterize surface runoffs

# - quantity and quality 3) determine soil physical properties and evaluate soil microbial activity; 4) determine groundwater chemical properties; 5) characterize surface water quality ofreceptor stream, river, lake, orpond and assess the effects of mning and standing water on aquatic biota. Throughout these programs sufficient samples were collected to ensure statistical and reasonable confidence levels. Monitoring was also carried out during storms. The ideal storm was one that involved first freezingrain that later developed into rain. This meant that chemicalswould be used 

### as an anti-icer or de-icer and there would be a subsequent good flush to the nearby watersheds. Selectingthe best storms to monitor was difficult. While weather predictions for the 

### next 2 to 3 days are generally good for most purposes they are too imprecise for efficiently mobilizing a field crew. Careful coordination with the airport staff improved the situation but there were still problems. Some stoms dwindled markedly before arriving in Nova Scotia, some were delayed and therefore occurred during warmer time periods, and some brought rain or snow instead of freezing rain. The surfacewater program 

### was designed tci monitor contaminant concentrationsadjacent to the application surfaces 

### as well 

### as the 'effectof downstream attapuation. 

### In areaswhere there might be some overlapin the influences of the two components (urea and 

### KA, (=MA 

### or NaFo) samples were *dl@ 'for .tfirs~&ipacts'oE bath,wea.md. JCA, CMA 

### or NaFo, '

. 

## -

. - .'

. * ?- 

### . &*,Y ; .- -. .. - *
, , The locations of the soilwater lysimeters and groundwater monitoringwells were deigned tobe as close as possibleto, and within theflowpaths leading from the application surfaces, but outside of operationally restricted areas. For example, due to restrictions imposed by

- -- . - . C . .. . ,. __. AD1 Nolan Davis Inc 218059-154-.IComparison Repon RunwayDeicers 'bnspon Canada Page 10

snow clearing requirements, the installations within the Urea study area had to be greater than 15 metres (50 feet) from the active runway surface; and within the 

### KAI CMA/NaFo study area, greater than 9 metres (30 feet) kom the taxiway surfacc Field personnel could not work within 46 metres (150 feet) of the tarmac, unless 

### an escort was present who could maintain contact 

### with the air traffic control tower. 

### Since the 

### soil fysimetermonitoringwell installationsand surface watermonitoringstationshad tobe inthis zone, escorts were essential during all field activities. For the control area, the ldcations of the surface water monitoring stations, roil water fysimeter, and groundwatermonitoringwells were selected to emulate samplinglocationsat the other study areas as much as possible. 23.1 Soils Sampling and Testing Pmgram Soil samples were collected to test their physical properties prior to, and after, the application of de-icers. Three soil samples from each study area were tested for their physical properties (i.e grain sizc, AtterbergLimits, and moisture content). 

### In addition, roil sampleswerecollectedand subjectedtogreenhouse teststo determinesoilmicrobial activity. (See 24.2) As in-situ testing proved impractical, soil permeability was examined theoretically (HazenWilliams method) using grain size analysis of the soil samples collected. 23.2 Surface Water Monitoring Program Whereverpossible, establishedTransportCanada 

### (TC)monitoring stationswere used during this study, thus providiiga continuous database for the evaluation of historical trends. As noted above, three study areas were selected for the field test of the e&ronrnentaJ impacts and of KA/CMA/NaFo and 

### Wea. These included a control stream (control) drainingthe southwestcornerofthe HaUaxInternationalAirport complex,a stream 

### (Leech Brook) draining part ofTaxiway,Deltato which 

### KA/ CMAlNaFowas applied as a de-icing treatment duringthe studj@A/CNM/N$FOstream);andMiller Brook(urdrains the eastern portih of RunwaF 15-33 to which urea was applied as 

### a de-icing treatment. A ditch rmvngnmoff'frorn the Tadway Delta subdrains (Station 

### R1) in the KA/CMA,/NaFotreatmerit areawas also sampled.

AD1 Nolan Davis Inc -21-0059-i%1

. , ..Comparison Repon Runway De-iccn Page 11 Transport Canada

Within the KA/CMA/NaFo studyarea, the surfacewater monitoring (measurementof flows and collection of water samples was done at 8stations (see Figure 1-3): Within the 

### urea 

# 1 study area, the surface waters ere monitored at 4 stations (see Figure 1-3): Two surface water monitoring stationswere establishedin the controlstudy area. Significant surface flows only occur during, and for a short time after, precipitation events. Therefore, whenever possible, the sampling eventswere adjusted to follow major precipitation events. The water samples were tested in the field for pH, conductivity, temperature and dissolved oxygen content. Given the nature of typical winters in the area, it was anticipated that major precipitation or snowmelt events might occur over the course of the winter. Therefore, storm event monitoring was undertaken 

### as a component of this project. Three freezing storm events were monitored during all yean of the study. Monitoring was conducted prior to, during, and after, the storms to establish pre and post-storm trends. Surfacerunoffand streamwater sampleswere collected, flowsmeasured, andmeteorological conditionsmonitored, overthe durationofthe stormsand continuedintothe stormrecession period. Groundwater and off-site surfacewater stationswere monitored prior to, and after, the stonn event. Thewater quality data and flow measurements collected during the storm events were used to define the variation in contaminantloadingrates throughout the storm cvents, as well as hydraulic loadings which were entering the site receptor streams. 

### 233 Groundwater Monitoring Program The datareview suggeststhat thebedrock isthe major aquiferandthe upperhctured 

### zone is the mast important location for monitoring well installation This zone represents 

### a potential quick release pathway for contaminants to leave the site, since it generallyhas the highest groundwater flow velocity with the least attenuation of contarninants. The relatively impermeable nature of the till, suggested that the pkntid rate 

### of contaminant migration within this unit would be relatively minor, and that a significant

. amount ofattenuationwould Wrcly occur along tbe ~~~rkvates flowpath 

### As e result, the till was considered to be a less likely source 

### d ~n~~~t mCgrtitibn and, therefore, 

### a Jess important target for monitoring wells.Comparison Report Runway Deicers Page 12 Transpon Canada

Todefinethehydrogeological conditions, thebackground chemical quality and thepotential impacts of 

### KA, 

### CMA,NaFo and urea on groundwater quality, monitoring wells were installed within each designated study area Within the KA/CMA(NaFo and 

### urea study areas, monitoring wells (MW) were installed within the shallowbedrock atthree locations. Themonitoringwell locations werebased upon thehydrologic conditionsand restrictions in proximity to the runway. They were designed to intercept any plume originating from the application surface and within the shallow groundwater flow system. The monitoring webprovided information on the hydraulic gradients, hydraulic conductivities of the shallow bedrock, and 'permitted the collection of groundwater samples. The data collected provided information on the orientation of the water table surface, probable direction of shallow groundwater flow, the chemical quality of the groundwater and the potential impacts of KA/CMA/NaFo and urea on groundwater quality. Samples were collected from all web during each sampling event. The samples were measured in the field for temperature, pH, conductivityand dissolved oxygen content. 

### In addition, one of the monitoringwells in the KNCMA/NaFo 

### area was monitored during the storms to try and determine the rate with which KA/CMA/NaFo might be enteringthe groundwaterflow system. Soilwater could not be monitored dueto frozen soils over much 

### ofthe winter season. 23.4 Soil Water Monitoring Programs An attempt was made to the characterizethe unsaturated soilzoneby collecting soilwater samplesusing tube-type suction lysimeters. Within both the KA/CMA/NaFo and urea study 

### areas, lysimeters were installed in three locations (Figure 

### 13) in the vicinity of the groundwatermonitoringwells. Thesoilwater samplesin thelysimeter tubeswere collected with 

### ahand pump. Samples were collected fromthelyshetertubeswitha syringeand were tested in the field for pH and conductivity. Soil water samples could only be collected whenever it was not frozen.

.... '3 >.- -

...


## -- -.,.. 

### . .... - -'*.'.=. -4 

### .,. Daily meteorologi&l data (pr~dpita~o~,'~$& 

### sj&l: inid direction, temgkratyriix were obtained from ~nvironm&t-enada's ~@os~heric'~n@onme~

. , ,. 

### Service (AES) station at the Halifax Airport, over the duration of the study. 

### 'these data were supplement~d by observations made by field personnel during the fieldprograia

AD1 Nolan Davis Loc 21-0059~1563Comparison Report RunwayDe-ices Transport Canada Page 13

2.4 Biolonical Field Sampling Procedures Biological components which were examined on the three streams being monitored were phytoplankton, periphyton, and benthic macroinvertebrates. Water temperature and pH were measured at each site and samples were taken to determine the chlorophyll g. Samples were also taken for phytoplankton cell counts at two sites on each of the test streams. Samples of benthic macroinvertebrateswere taken on each sampling occasion. Sampleson flowing water stretches with gravelly bottoms were sampled with a Surber Sampler. Substrate was loosened and freed of organisms and captured in the attached net Muddy bottom orpond environmentswere sampledin triplicatewith a Ekman Grab. Samples were sieved to eliminate fine sediment and then preserved in formalin. 2.4.1 Artificial Substrates Artificial substrates, consisting of plexiglass plates, were placed to 

### give a standardized measure of microscopic plants growing on surfaces in the stream. Plates were replaced in midoFebruaryand mid-March and removed in mid-April. 2.4.2 Soil Microbiology and Surface Vegetation Two sets of soil core samples from each of the 

### K& CMA and NaFo, urea and control sites were collected in each of the study years. 

### Five core samples 7.5 

### cm in diameter and 10

### cm inlength were coktedfrom the corners and centre of each of three 1m2plots at each site. 

### The samples collected in March were obtained from locationswhich overlappedthose fromwhich the core samples were obtained in November of the previous year. Prior experience has shown that this soil sampling pattern yields excellent reproducibility of subsequent chemical and biological snalyses. 

### These composite samples were used for the analysis of bacteria and 

### fungi and for the dctemination 

### of soil respiration rates.

-,Comparison Report Runway DGicen Tnnspon Canada

2.43 SurfaceVegetation Sixteen blocks of soil samples, collected from the KA/cMA/NaFo study area, were placed 

### inplastic trays, in a light and temperature-controlled greenhouse. Waterwas applied at two thirds the annual precipitation rate of the Halifax International Airport to simulate precipitation during the months of late autumn, winter and early spring. A light regime of 12hours on and 12hours off was employed, and the temperaturewas regulated to always be greater than 

### 65' 

### F. KA, CMA or NaFo was applied either bi-weekly with the irrigation water to eight block samples at concentrations ranging from 0 to 5000 mgR, or in a single application to each of eight Hock samples at concentrationsranging from 0 to 5000 mg/kg of the dry weight of soil. Theprocedure was designed so that, at the end of the evaluation period, both pairs of test blocks would receive comparable mass quantities of de-icer. A seventeenthblock was used to determinethe moisture content and bulk density of the soil The concentrations of de-icer used 

### in these tests ranged from the most probable concentrationsto be encountered (0-500ppm) to those greatly in excess of those likely to be encountered (1OOeSO ppm), whether thesewere applied over a ten-week period or all at one application as would occur in a reagent spill. 

### In both tests, the total amounts of deicerapplied were similar, allowingthe evaluationof the differencesbetween application over a period of time and one large, possibly catastrophic, application. At the end of the tenweek growth period, the surfacevegetationwas harvested, dried to a constantweight at 

### 85% and weighed. 2.4.4 Quality Assurance Qualitycontrol procedureswereinstitutedfor thefield samplingand the analyticalprograms. Thisincluded thecollection and analysisofblind duplicates andblanks, blind spiked samples, . trip blanks, field blanks and equipmentuse blanks. A fieldprocedures manual was developed 

### as an integral component of the field program design. The manual defined field procqlvres, sampling- protocol, and quality assurance procedures for the study. 

### Inaddition, samplingrecord sheetiwere developedwhich defined data collection requirements. A chain of custody..form w& 

### -also developed which accompanied each group of samples.

a1 Nolan Davis Inc '21-0059-154-1Campatison Repon Runway De-ices Page IS Transport Canada

2.5 In-house Laboratom Exwriments Laboratory experiments were conductedtoinvestigatethephysical and chemicalproperties of 

### KA, CMA and NaFo. The laboratory experimentswere:

. a Determination of 

### pH in a 15% and Saturated Solution of CMA/NaFo Determination of solubilityof 

### CMA and NaFo in water a Determination of exothermicity of KA, CMA and NaFo Evaluation of the degradationrate of KA 3.0 

### COMPARISON OF 

### THE PERFORMANCE

### OF 

### UREA,

### KA, CMA 

### AND NaFo 3.1 Site Desimation The surfacewater monitoring station identifierswere consistentlyused for the three de-icer studies. The de-icerstudy areamonitoring stations(those 6stations located on the Taxiway Delta side of the study area) have had three distinct identifiers to distinguish each of the studies. Test de-icer locatioxis are therefore called 

### NDUF/K in this report. TABLE 

### 3-1 SiteDesignations
Site Designation

..

3.2 Background Urea Study Site

# - Surface Water Station Control Study Site

# - SurfaceWatcr Station Test Deicer Study Site

# - C-CMA F-NaFo Surface Water Stations K-KA Monitoring wells

# - all sites Biological Stations 4
The effects of the three deicers must be considered in the light of an acid drainageproblem and high sodium level situation at the 

### Airport. . -

AD1Nolan Davis Inc 218059-1541Comparison Report Runway Deicers Transport Canada Page 16

3.21 The Acid Drainage Problem Someparts of the airport arebuilt on areas ofpyritic shale (Stea and Fowler, 1981). During construction thesewere exposed and, inplaces, extensivelyfractured. Pyriticminerals,in the presence of air and moisture,willvery slowly oxidizeto sulphuricacid. As the soil moisture becomes acidic it creates ideal conditions for enhanced bacterial activity. Species, such as Th.iobacillus ferrorddans can use the free energy generated by the oxidation and thereby promote the oxidationrate. Thisin turn raisesthe temperature and results in an even faster oxidation rate. Someperiod afterthe initialexposure, usually afewyears,the acidicproduction ratereaches an equilibriumvalue. By then severe environmental damage is apparent. Surface streams 

### look barren and frequently have deposits of iron precipitates on rocks and vegetation, aquatic life is killed or driven away. The limiting factor for this reaction is the availability of oxygen although the rate is 

### also affectedby temperature. Typically there is adequate oxygen down to one to two metres below the surfaceof unsaturated soil. So acidic production can continue at depth evenwhen the surface is fkozen. Sulphuric is a strong inorganic acid and it readily dissolves metals such 

### as iron and aluminum. During the tests, the presence of these metals in the surface and groundwater samples was more easily related to the anticipated acid generation tben to the presence of any of the de-icen. For example in the control surfacewaters of NDB-1 (Figure 3-1) 

### iron

- - and aluminumlevels drop as the temperature drops and acidproduction slows. At the same

.

- - - - time 

### pH ti-, x~lphate drops; as apctcd-l''breyt~~e occurs inthespring, -This

- pattern is generally followed throughout the test area and can be seen in Figure 3-2 and shows that many sections of the airport are effected by exposure of slate during the initial airport construction. Groundwaters follow a similar trend as shown by the results for two monitoring wells in Figure 3-3. Similar data were collected for the 

### KA study during the 1993-1994season .>

.. ... -. ..-. . . -

### Station 

### NDB-1



### . RegularMonitoring



### Station 

### NDB-1

Regular Monitoring



### Station 

### NDB-1

Regular Monitoring



# I ~nhronrnehd Management Halifax. Nova Scotla

### Station NDF-1 RegularMocrirori~



### Station NDF-1 Regular Monitoring 

### Station NDU-2 Regular Maocing



### Station NDF-1 f3egular Monitoring 

### Station 

### NDU-2 RegularMonitoring

A 

# -=" AD1 

### Nolan Davis 

### Inc. 

# eQq ~&ineerin~ and Environmental Management Halifax, Nova Scotia . - , FIGURE 3-2 NaFo AND UREA YONlTOFUNC STAnONS-h91/1992

. .I: I..

. ,
. .

### Station MW-2 Regular Monhing

l 

### Station MW-2 Regular Monitoring 

### Station MW-3 Regular Modtorlng



### Station MW-3 RegularMonitoring



### station MW-2 Regular Monitanng 

### Station MW-3 RegutarMonUoring

A 

# =@ AD1 

### Nolan Davis Inc. 

# 6'~$ Englneerinz and ~n;ironmental Management Halifax. Nova Scotia

.Comparison Report Runway DGictrs Thansport Canada Page 18

3 Sodium Levels Therearethree sources of sodiumat this

### airport. 

### First,the native soils contain a widerange of sodiumlevels. This sourcewill provide aflush in the spring both from material dissolved, but relatively immobile 

### in the winter and fkom erosion due to the spring 

### nm4. The second sourceis the sea. HIA isjust over 30 ID fromthe Atlantic Ocean. The nearby coastline is directly 

### in the path ofeasterlygales which can 

### run the 

### full fetch, unobstructed, fromIreland. Theviolently pounding surfshoots a finely divided sprayhigh intothe air, and the gale force winds drive it inland. The last source is road salt (sodium chloride), a de-icer that is used on all roads around the airport. Vehicles used by airportmaintenance and security travel on the roads and taxiways and cakes of ice and salt form on wheels and the undersides of the body and these can be transported onto the taxiway. The influence of road salt is clearly seen in the background stations, NDB-1 and 

### NDB-2 (Figure 3-4). These arejust downstream of a public road that is salted during the winter. The figure shows the changes in sodium concentration as it relates to the major storms. The relationship with the road salting program is evident. 33 Impact of De-icer Chemicals The results of the monitoring programs were used to evaluate the impact of the de-icer chemicals on various components of the local environment The level of impact was assessed against the values obtained at the control stations (ie. background values or thosc unaffectedby the de-icen chemicals,though not necessarily otherairporteffects) andtypical data from other appropriate studies. Interpretationagainst these standardswas sufficiently obvious that no attempt was made to statistically evaluate the data. The 4 

### mg/L ammonia criterion is useful at this site only. It was chosen as a within-theairport control Jew1 that was baed on the sensitivity of local species and the potential for dilution at the airport b~und~j.

- r ._ . L ' a, 33.1 Urea I .- ,,. w- . -.. . Urea is an arnide of &bo& acid and contains 47 percent nitrogen by weight. It is a solid crystalline substance that depress the freezing point of water down to about -100C (see Figure 1-1). Urea is very soluble, evenk cold water-(459 g/Lat OC).

- A, , AD1Nolan Davis Inc

. . 21-0059-lSl

$ r

### Station NDB-1 Regular Monitoring



### Station NDB-2

Regular Monitoring

A 

## AD1 Nolan Davis 

### Inc. 

# ewq Engineerin~ and Eo%ronrne6.t~1 Management Halifax. Nova ScotiaStation NDU-2 Regular Monitoring



### Station NDU-3

RegularMoniton'ng 

### Station NDU-2 Regular Monitocing



### Station NDU-4

Regular Monitoring

.... -@.

### AD1 

### Nolan Davis Inc.

, 

# PWq Engineering and Environmental Management

- ,.# Halifax, Nova Scotia



### . . I
. i 

### . I

, , *:. - , ef,=- . " . ' FURE 3-5

.A~ONU~~~ AT UREA STATIONS \ .. . .

I-.-.An..,.,. ,,,* .- .+h,.-. .:A. .........Comparison Report Runway DGiars Transport Canada Page 19

The impacts of urea have been well known for some time. The key concern is with the breakdown product, ammoniawhich is toxic to fish at low concentrations. For 

### this site 

### an alarm level of 4 mgLwas chosen 

### as thiswould not cause problems with the impoverished 

### and tolerant fauna on the airportproper andwould be diluted by thetime it reached off-site locations. These studieswere not intendedto significantlyadd totheknowledge ofurea,but instead it was used as a yardstick against which the other de-icers could be compared. As expected, after the application of urea, ammonia levels rose, often above the level of concern. This is clearly seen in Figure 3-5, which provides examples of results £rom three surface water monitoring stations. Ammonia was alsomeasured in samplesffom the KA/CMA/NaFotest site. This was trad to a flow of groundwater from a taxiway underdrain which emerged at station NDCjF 3. Surface water systems downstream of this point also have high ammonia levels itquentty exceeding the 4mgLlevel (Figure 36). Upstream the levels are below 

### l6mgL Because neitherKA,CMA norNaFo can form ammonia, it is readily apparentthat the sourceis 

### urea It also indicatesthat,giventhenecessary subsurfaceconditions,urea-generated ammonia can travel widely and pollute several surface water systems. 33.2 CMA (Calcium Magnesium Acetate) 

### CMA is an illdefined compound of calcium magnesium and acetate. Each molecule has three to six calcium ions and sixto seven magnesium ions. It is an off-white powder that can lower the fieezingpoint ofwater to about -30°C (see Figure 1-1). The commercial product is supplied as round pills, about two mm 

### in diameter. 

### CMA breaks down carbon dioxide and water. The 

### CO,is trapped in water to fmm.carbonic acid which can form salts with calcium and magnesium. None ofthesebreakdownproducts would be the cause of

### concern except 

### in massive quantities. 

### In general CMA had little or no impact on water chemistry. At 

### HIA it might even be slightlybeneficial, as it helps to reduce the acidity somewhat. From Figure 3-7it can be seen that acetate concentrations increasein surface water during the winter and decreases in the spring, changes which coincidewith the applicationtimesof CMA The levels generally do not go above 10 mgR, probably related to the fact that acetate is easily biodegradable. Changes in aidurn and magnesium levels are not 

### as well correlated to 

### CMA application and correspondmore closelywith thebackground chemisy. 

### In Figure 3-8 NDC-2& NDC-3 and NDC-S show calcium and magnesium lewels that 

### 3-2

AD1 Nolan Davis Inc 21-BlbSSa-Wl

### NDC-3 Regular Monitoring(1) 

### Station 

### NDF-3 Regular Monitoring

-



### Station 

### NDF-4 Regular Monitoring

- .. A 

### ma'@ 

### ADI 

### Nolan Davis 

### Inc. 

# Gwq Eneineerinr and

- - ~ncironmehl Management Halifax, Nova Scotia --. .-*
. . . FIGURE 3-6

. - AMMONIA UWEU AT CYA AND NaFo STATfONS

### Station NDC-2A 

### Station 

### NDW Regular Monitoring Regular Monitoring

1-



### Station 

### NDG3

Regular Monitoring 

### Station 

### NDG5 Regular Monitoring

A 

# --=" AD1 

### Nolan Davis Inc. 

# awq Eqineering and 

# I

FICURE -3-7 ACEX'ATE RESULTS -AT C3dA STA193NS Environmental Management Halifax. Nova ~cotia- 

# IComparison Report Runway Deiars Transport Canada Page 

### a

decrease slightly in mid-winter and rise in the fall and spring. However, this pattern is also true for the urea side (see NDU-2). The background values, NDB-1 and NDB-2, only marginally follow this sequencebut note the concentrations in 

### all samples are similar. This information suggeststhatthe acidproduction and metal dissolution,which ismore seasonally dependant,is a likelier explanation for the calcium and magnesium levels (and othermetals too). During the storm events the leading data showed that a slug of reagent moved through the area, generally with a peak at around 24 hours afterthe onset of the storm (Fig. 3-8). The peaks for calcium and acetate, return rapidly to more baseline levels. Ammonia, £rom contamination from urea, alsorose sharply and then feL 

### In the January 1618,1991storm (Figure 3-9)theiron and aluminumlevelsdonot changenoticeably. This was expectedfrom other research. During the February 19-21, 1991 storm, however, iron and aluminum followed the sametrend as calcium and magnesium and showed a good correlationwith the CMA application (Figure 3-10). The most likely explanation laid with the nature of the stomthemselves. The first storm occurred when there was a large runoff due to melting of snow pack In the second storm there was less runoff due to a minimal snowpack 

### This was reflected in the loadings. Theremay have been a mwement ofmetals in the first stom but this was not easyto detectbecause of the dilution dueto runo& Becausethe mwement of calcium and magnesium was twice that of the other metab (as seen in the second storm) the loading for these two metals were less masked by dilution in both storms. A limited investigation of the biological impact of the CMA treatment found no effects on phytoplankton,periphyton or macroinvertebrateabundance. 

### Thiswasalsotrueforthe ureaimpacted streams. Both periphyton and phytoplankton were low and stable at 

### all sites Although no large differences were observed for macroinvertebrates it is possible small changes are missed due to the high variability in macroinvertebrate numbers. CMA did not affect the in-situ concentrations of bacteria (either anaerobic or aerobic, psychrophilicor mesophyllic). Similarlyit did not have an impact on eitherpsychrophilicor mesophyllic fungi. This was supported by the unchanged soil respiration characteristics. Vegetativegrowthwas onlyaffectedabove

### , hi-weekly

ps.j'.e applicationrates of 1000mghorsingle applicationsof 169

# urn2.A single 

### application of 845 

### g/m2 stopped 

### all plant growth. Such high levels would not normally occur, unless pure reagent was dumped direaly on the ground during 

### a spill.

AD1 Nolan Davis he. ' . I* . . 21-0069-154-1

1 It:. >

### Station 

### NDG2A

Station 

### NDC-3

Station NDCd 

### Station NDU-2



### Station 

### NDB-1 20- 18*, 

# n

Station 

### NDBP

A 

# =' AD1 

### Nolan Davis 

### Inc. 

# ew9 Engineering and Envirsnmeutal Mmanrement 

# I

Halifax, Nova ~cotia-

. 

# IA -lo 

### AD1 

### .Nolan Davis 

### Inc. 

# mRq ~n~ineeiik~ and Environmental Management Halifax, Nova Scotia

.... I,.. .Station NDC-4

### - Loading StormTebruary 19-21 .I

991 Station NDC-4

# - Loading

A 

# =" AD1 

### Nolan Davis 

### Inc. 

# t((r?wq Engineering and . , Environmental Manaeement RCW 3-10 FEBRUARY 19-21, !B91 SrORU XBADINCS AT STATION NX-4 Halifax. Nova ~cotia-- 

# IComparison Report Runway Deicers Transport Canada

333 NaFo (Sodium Formate) NaFo is the sodium salt of formic acid. It is pure white crystalline powder that can lower the freezing point of water to about -16T (see Figure 1-1). The commercial product is supplied as a crystalline, angular pellet one to four 

### rnm across. NaFo is considered a good food source for bacteria and breaks dorm to 

### CO,and water with the release of sodium. 

### h generalNaFo alsohad littleorno impact onwater chemistry. Concernswerthe increase 

### in sodium were diminished because it is difScult to discern the effect of sodium addition against the existing, large background fluctuations. Thebackground sampleshave levels of 20-80 mg/Lprior to any saltingand this rises to 140to 180mg/Lafterthe use of salt on the nearby road (Figure 3-4). A similar pattern but generally at lower levels was seen for the sodium formate stations (Figure 3-11, NDF-2A and

. NDF-3). Station 

### NDF-5 was downstream of the road that impacts NDB-1 and 2 and the road salt contributionwas again evident. The sodiumvariation on the urea sidewas stillvisible but less pronounced. Station 

### NDU4 was again downstream of the road and was clearly salt contaminated It was clear then that, while sodium formate did contribute some sodium to the surface waters, it was not the sole nor the major contributor. Fonnate was difficult to detect in most samples. Only 14per cent of the samples analyzed

I had a detectable level of formate and only 4.5 per cent had a value greater than 1

### mgL Out of over 100 samples there were but two significant values (20 and 38 mgh). This suggests formate is not an important or persistent contaminant Sodium and formate concentrations rose after the application of de-icer to the runway. Formate often proved difficult to detect and this could be due to a limitation of the analytical method. It was difficultto obtain 

### a standard,but every effortwas made to 

### ensure reliable results. Sodium analysiswas a lot simpler and was well established. It was easyto follow the changes in sodium level. These may not all be attributable to sodium formatc Each storm event did increase the run-off and would therefore flush any mobile sodium. Such a flush would follow the same pattern. It was much more likely, however, that the

. major portion of the sodium increase comes ftou de-icer.

AD1 Nolan Davis loc 21-9-154-1

. ...

, ,

### Station NDU-2 Regular Monitoring



### Station NDF-3

Regular Monitoring 

### Station NDU-3 Regular Monitoring



### Station NDF-5

Regular Monitocing 

### Station NDU4 Regular Mmitocirrg

A -me 

### AD1 

### Nolan Davis 

### Inc. 

# qwq hgincerln~ and 

# I
En&onrne6t.l Management Halifax, Nova Seetia 

# IComparison Repon Runway De-icers Transport Canada Page 32

However, during storm events, as with ChM, slugs of NaFo reagent also appeared to

### move through the watershed. This was more difficulttoevaluate

### as the resultswere compounded by the presence of local sodium and the difficulty of detecting formate, as indicated above. Assuming the results were at least partially due to NaFo additions then the material took more time than CMA to peak at the monitoring stations The pattern indicate the de-icer moved through the environment with a peak at various times up to four or five days after the 

### beginning of stom This was longer than expected based on the 

### CMA experience. However, the concentrationsin the surface water system normally remained low, with sodium for example usually around a few mg/L The impact on other soil constituents was hard to define as it was complicated by the background chemistry and the change in flow regime caused by the storm. A number of variables dochange in apparentresponsetothe influx ofNaFo, but these changesare

### minor (a few percent). overahtheimpact of NaFo was low and was lost to the area within a few days. The limited biological study found no effixt of the treatment on either the test streams receiving NaFo in terms of phytoplankton, periphyton or macroinvertebrate abundance. Also, no effects were observed on the in situ concentrationsof bacteria or fungi. The roil respiration characteristics were also unaffected. Bi-weekly applications of NaFo in 

### ucw of 3500 mg/L did inhibit plants. Single applications of 

### 85 g/m2 caused a 

### 50 per cent inhabitation. Above 850 g/m2there was almost total inhabitation of 

### growth.Comparison Report

. Runway De-icers Transpon Canada Page 33

KA is the potassium salt of acetic acid, made by reacting potassium hydroxide and acetic acid. It is a white deliquescent powder that can lower the 

### freezing point ofwater to d8"C The commercial product is supplied as a 50 percent solution, usually with corrosion inhiiitors and an identifying dye. Acetate ion can be broken down by bacteria but is more stable than formate ion (that is less readily used 

### as food by the bacteria). During the first storm event acetatewas only detected at NDK3. Here the levels were low and erratic, with separatepeaks at 12, 19and 24 hours. These appearto relate to the rate ofprecipitation. There was a good correlation between the increase in flow rate and the increase in acetate level (Figure 3-12). As the flow rate dropped 

### so did the acetate level, indicatingthe decrease in physical flushing,similar patterns occur during storm event 2and 3. Because of its location, NDK-3 often shows the highest concentrations of a particular variable. It was believed that this was due to this station receiving 

### a combined runoff from both the Tadway Delta and the underdrains. Downstream of NDK-3 (at NDK-4, NDK-5 and NDK-6) the brook received more runoff from areas not impactedby KAand was usually lower in Kdue to dilution. Howmr,when the precipitation rate was high enough to produce a flow in the road side ditch at the end of the taxiway (NDK2A) then there was rapid flush of de-icer, giving increased levels at NDK2A and NDK4. This is not entirely consistent and the explanation may lie with the erraticflow behavioun of 

### NDK2. The zone around NDYd often floods and the surface has been seen to flow northeast and southwest. T%ismeant acetatewould be flushedawayfromNDK-3 andNDK4, at least 

### for a period. The most illustrative example was stom 

### No. 2 Acetate was detected at all four NDK stations. A large initial ihsh pushed acetate thraugh NDK2 and NDK2k Flows and acetatelevels are more emticdwmtrearn bob &a"il.skw 

### m tendency towards 

### an initial flush followed by a decrease of acetate (see Figure 3-13). Thehypothesisthat acetatewas removedby dilution and dispersion, rather than degradation was supported by laboratory experiments. Tests with typical airport runoff water showed that it did not degrade unless fertnized with phosphate and possibly ammonia.

# Station NDK-3 Storm Monitoring Event No. I



# Station NDK-3 Storm Monitoring Event No.1

A 

### AD1 

### Nolan Davis.

### Inc. - 

# QR4 Engineering and Environmental Management Halifax, Nova Scotia .. 

# ___ FIGURE 3-12 EOMPARISON OF ACETATE AND FXDW RATE HALIFAX INTERNATIONAL WRPQRT - -

### Station NDK-2 Storm~gEverrtNo2 

# I

Station NDK-2A Stonn Moniton'ng EventNo.2

0J.9: ::GJ 100 ms abb 470 570 7s mol01017w~~ Ti (minut.8) 

### Station NDK-3 Storm McmItoringEventNO2 + Acetate

A 

### AD1 Nolan Davis 

### Inc.

# I FIGURE 3-13 Engineering and ACETATE LEWIS DURING A SrORM EVENT Environmental Management IMUFAX DITERNATIQNAL MRPORT Halifax, Nova Scetia -Comparison Report Runway De-ictrs Transport Canada Page 36

The use of KA did increase the BOD, significantlyat the NDK stations. Figures 3-14 and 3-15 show the BOD, levels at two stations, NDK-2 and NDK-3, during two storm events. As the normal BOD, levels during the previous s~dies and at other sites during this study was typically less than 10 and frequently less th& 5 mglL then results from 5 to 70 were surprising. Figure 3-16depicts regular monitoring data from NDK-4 and NDKd and sham how closely the BOD, is related to acetate levels. 

### This could be directly compared to the CMA data. Again there was a dose correlation but the levels are substantially lower. While it is clear that 

### ICA increases the BOD5the cause was hard to define. 

### In the airport conditions, the KA does not degrade in the normal residence time in the surface water system. Although potassium acetateis 

### a chelating agent, therewas little evidence that the bulk was remaining on site and reacting. It was possible that the excess caustic, present in the commercial product, temporarily increases the pH causing an increase in bacterial activity in other materials in the soil and water. It was possible that a residual amount 

### is being absorbed into the interstices of the runway an reacting with a mwaycomponent or contaminant. The products of this reaction were flushed with the following storm event and result 

### in an initial 

### high BOD, which drops with the. Whatever the mechanism the increase in BOD, was strongly correlated with the acetatelevels. The BOD, levels measured arc equivalent to a stream polluted with untreated sewage. However, it must be remembered that the impact at HIAwill not be as severeas the results would indicate, asthe BOD, measurement is done at lS°C. Typical water temperatures at HIA in the winter arejust above (PC 

### so biological activity is retarded.' By the time the water temperature was high enough for sigmficant biological activity it would be long after the season of de-icer use. At other airports this may be a more important consideration. A limited investigation of the biological impact of the 

### KA treatment found no effects on phytoplankton,periphyton ormacroinvertebrateabundance. 

### Thicwas 

### alsotrue forthe

### ureaimpacted streams. Both periphyton and phytoplankton were low and stable at all sites Although no large differences were obs.e~~ed for macr0invertebrat.a it is possible smaU changes are missed due to the high va@ib@g-jn macroinvertebrate
..___.

### __ numbers. ..-_ 

### KA did not affect the in-situ conceitfiiid11~ of 'bacteria (either .anaerobic or aerobic, ' psychrophilicor mesophyllic). Similarly if did 

### nothawasimpacton eitherpsychrophilicor mesophyllic fungi. This was supported 

### k$ the ~nchangid soil respiration characteristics.

-'. . I AD1 Nolan Davis Inc , .

.. 21 -0059-154-1

## Station NDK-3 Storm Monitoring Event

### No.2

A lo 

### AD1 

### Nolan Davis 

### Inc. engineering md Enviroarneita% Management Halifax. Nova ScotirStation 

### NDK-2 Storm MonbhgEmitNo.1



### Station 

### NDK-2 stmMorritoring€vmtNos

, , . . A 

### -w".ADI'~olan 

### Davis Inc. FIGURE 3-15 

# mW9 bginee6ng and BOM~~UJVES.~UR~NG SFOW

### & Environmental Management WU.

.. mATIONALAIRPORT Halifax, Nova ~cotia-

. - 

### IStation NDK4 Regularmocirrg

Station NOC-4 Regular Monitorirrg , 8--- 

# --

A 

### AD1 

### Nolan Davis 

### Inc. 

# Awg Engineering and Environmental Management Halifax, Nova Scotia Station NDK-4 WMorwtoring

Station 

### NDK-6



### mmw

Regular WmitorirrgComparison Report Runway Deicers Transport Canada Page 40

Vegetative growth showed only 50 percent or less inhibition at bi-weekly application rates of 2400 

### mg/L or single applications of 20 glrn2* Such 

### high levelswould not normally occur, unless pure reagent was dumped directly on the ground during a spill. 

### In summary, 

### KA had little detectableimpact on the surface water except for BOD and no detectableimpacton groundwater,vegetation and othersoil and streamlife*It was superior to 

### urea, in that it did not produce toxic levels of ammonia. For place such as 

### HI, there may even be a slight benefit due to KA's alkalinity. Operationally KAwas less satisfactory

### thanurea. Itworked better as an anti-icer than a deicer. Snow more readily stuck to the runway surface after KA application than after urea application Also, as it was a liquid, it needed a special sprayer.

a.

. . AD1Nolan Da%shc 214059-1561Comparison Report Runway De-icers Transport Canada

4.0 

### CONCLUSIONS

### AND RECOMMENDATIONS 4.1 Conclusions The results of three years of on-site evaluation at 

### HIA indicate that 

### KA, CMA and NaFo are more environmentally benign de-icen than urea. NaFo

### was very difticult to detect in the environment, indicating a rapid breakdown. Sodium levels were currently obscured by sodium input from other sources. It must be remembered that only 15 tons of NaFo were used in this experiment and normal operations would require around 200 tons of de-icers. IfNaFo use is increased then sodium levelswould have risen and may have had an impact. CMA was found at higher levels and both acetate and 

### calcium and magnesiumwere easily detected. As HIA has an acid generation problem increased use of CMA would provide some buffering of this effect. At other airports the change in alkalinity and hardness may be less welcome. Potassium acetate was also more detectable than NaFo. 

### In particular therewas a significantincreasein 

### BOD, associatedwith the rise in acetatelevels. However, there was no other discernable impact. CMA was difficult to apply and left a very sticky residue. NaFo was much easier to apply and did a much better, more rapidjob than even urea. 

### KA,being a liquid, was applied in a different manner which makes direct comparisons difficult. 4.2 Recommendations From the results of the environmental studies, KA, CMA and NaFo can be used as de-icers and would give less environmental problems than urea. However, the initial operational problems noted during this evaluation would prompt the following recommendations: Urea, while operationally superior to all the de-ices assessed in this investigation, degrades to ammonia and creates 

### an environmental impact. NaFo is recommended over CMA as it degraded more quickly and is operationally superior. a Transport Canada should approve NaFo as an alternative de-icer for w at Canadian airports, but should develop proper laboratory monitoring techniques. TransportCanadashouldtentativelyapprove

### KA,but implementamonituring program to establish the impact on the BOD5created and the effect of the alkaline component.

-- AD1Nolan Davis Inc 214059-1%-1Comparison Report Runway De-iccrs port Canada Page 42

AD1 Nolan Davis would like to thank the staff at the Halifax International Airport, in particularAlyson MacDonald, Eloi Gaudet, and DaveDawe, for thecontinuing cooperation through two winters of frustrating storm activity. Our gratitude goes to 

### Dr. M. Silver, N. 

### Collins for their solid technical input. 

### Theproject manager would like to thank his colleagues atAD1 Nolan Daviswho stayed out for hours in the vilest of maritime weather to collect samples and take readings and then returned to the office to work on preparing the report. Finally, we need to thank our sponsors, Transport Canada, 

### Airports Group, and its representativesAlec Simpson, Lynn Warner and Victor Thorn. Their support was crucialComparison Report Runway De-ices Transport Canada Page 43

REFERENCES AD1Nolan Davis Inc 1994. Environmental Impact from the 

### Use of Potassium Acetate at Halifax International Airport. Report prepared for Transport Canada, Ottawa, Canada American Public Health Association. 1985. Standard Methods for Examination of Water and Wastewater, 16th Edition. Amrhein, C and J. Strong. 1990. 

### The Effect Of Deicing Salts on Trace Metal Mobility 

### In Roadside Soils. J. of Envirori. Qual. 19:765-772 Beak Consultants Limited. 1988 Mitigation Measures to Control the Contamination 

### of Stormwaterwith De-icer Fluids at Halifax International Airport. Prepared for Transport Canada, Rep. 2401.7 Bowman, J. 1990k Acute Flow-Through Toxicity of Sodium Formate to Rainbow Trout. Study for Hachst Celenese by Analytical Biochemical Laboratories Inc Bowman, J. 1990B. Acute Row-Through Toxicity of Sodium FormatetoFathead Minnow. Study for Hoechst Celenese by Analytical Biochemical Laboratories Inc. Bretherick, 

### L 1979. Handbook of Reactive Chemical Ham&. Second Edition Buttemorths, London. Burgess, D. 19%*Acute Flow-Through Toxicity of Sodium Formate to Daphnia mogna. Study for Hoechst Celenese by Analytical Biochemical Laboratories 

### Inc CanadianBritish ConsultantsLimited 1978. hvir~~mental Clean-upProgram Assessment Study, HalifaxInternationalAirport Prepared for the ~nvir~mental Protection Serviceand the Department of Fisheries and Environment, Halifax. Celmese Ific, 1991. 

### Sodium Formate De-Ires

,. Technical Information Bulletin.

Chevron Chemical Co. 1992. Chevron E36 Liquid Runway Deicer Technical Bulletins.

- AD1 Nalan Davis Inc 21-9-WlComparison Report Runway De-iotn Trsaspon Canada Page 44
Clayton, G. D. and 

### F. E Clayton Wtors). 1991. Patty's Industrial Hygiene and Toxicology. Fourth Edition. John Wiley and 

### Sons,New York. Clayton, G. D. and 

### F. E Clayton (Editors). 1978. Patty's Industrial Hygiene and Toxicology. Third Revised Edition. John Wiley and Sons, New York. Comfort, G. 1993. Laboratory Tests of the De-Icing Performance of Potassium Acetate, ' SodiumAcetate and Urea. SWIFT Workshop, Vancouver, 

### BC Daw, D. Personnel Communication. Dickerson, R. 

### C J. Campbell and M. Stankard. 1955. Further Operating Experience on Biological Purification of FormaldehydeWastes. Proceedings of the 9th Ind. Waste CodPurdue Univ. Ext. Ser. 87:33lW 351. Doetsdq R. 

### No and To 

### Me Cook. 1973. Introduction to Bacteria and their Ecobidogy. University Park Press, Baltimore. Doetxh, R.N. and 

### Cook, TOM. 1973. Introduction to Bacteria and their Ecobiology. University Park Press, Baltimore. Elliott, HA, 1987.EffectofCalciumMagnesiumAcetate ofHighwayMetalMobility

### in Soil. Journal of Environmental Quality, Vol. 16, NO. 3, 1987. Environment Canada, 1985, Technical Information for Problem Spills 

# - Urea, Technical Services Branch, Environmental Protection Service, Ottawa. Green, 

### AL., and Smith, 

### U. 1991. The replacement of ethylene glycol and propylene gIycoL kkheed Aeronautical Systems Company Georgia. Hart, 

### B.T. 1974. A Compilation of Australian Water Quality Criteria. Caulfield Institute of Technology. Australian Water Resoufixs'buncil, Techriical-paper,

### No. 7. Australian Government Publishing .---

Se"q,

, CanNqa.

. .

I' . ..L I . ,. U'. c, , . #- , t .... . .4 1 .. .. - ,, . . . Hawker, 

### L

### Eand Linton,

### k H. 1971;.l%c~borganiSm& FunctioG Formaand Eiwironment. Elsevier, New York.

.. , .

, .. . , . .. , . , . ..,

AD1Nolan Davis Inc- 21-0059-154-1Comparison Report Runway De-ices Page 45 Transport Canada
Hawker, LE and Linton,

### AH. 1971. Microorganisms: Function, Form and Environment, Elsevier, New York. Herlihy, 

### L J., J. 

### N. Gaalloway and A. L Mills. 1987. ~acterial utilization of Formic and Acetic Acid in Rainwater. Atmospheric Environment 21(1 l):2397-2402 Hodgson, 

### E R. B. Mailman and J. 

### E Chambers. 1988. Dictionary of Toxicology. Van Norstrand Reinhold, New York. Hoechst Aktiengesellschaft. ' 1990. Prufung derakuten Toxizitat 

### am KIeinkrebs Daphnia magna ubes 48 Stunden, Pharma Forschung Toxickologie und Pathologic, Frankfurt Germany. Homer, 

### R.R 1988. Environmental Monitoring and Evaluation of 

### Calcium Magnesium

. acetate (CMA). National Cooperative Highway Research Program Report 305. TransportationResearch Board, Washington, 

### DC. Huntingdon Research Centre, 1991, Acute toxicity to 

### Rainbow Trout, Reprot to BP Chemicals Limited, Hull. England on Clearway 1de-icer. Hydro Qual. Inc. Biodegradationof Ice-B-Gon and its Effect on Receiving WaterDissokcd Oxygen, (for Chevron Chemical 

### Co.). Institut fur gewerbliche Wasserwirtschaft und Luftrein haltung eV. 1990. Fschtest, akute Toxizitat, Koln, Germany. Institut fur gewerbliche Wassemirtschaft und Luftrein haltung eV. 1990. Bericht uber die Untersuchung des Produkes Landebahnent Safeway

### KA auf okologisches Verhalten nach Eintrag in 

### ein terrestrisch

# - aquatisches System Koln, Germany. Institute of Hygien of the District of the Ruhr, 198% Determination of Water Classhmd for Deutsche Report for BP Chemie GmbH on Clearway 1de-icer. Kato, 

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### in Biotechological Process, Alan 

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### Sons, New York, New York, 1948 Lumis, 

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. (. : 

### 90-117.. .*. 

### Nolan, Davis and Mociatq 

### Ltd, 

## la91. Epironmental,Impact 

### from the Use of Calcium Magnesium Acetate at:.Halifak (. Iht$~h$idilid ,.-. 

### Repit prepared for Transport

... 2. .. 

### .-

.. . \.1 .

### . Canada, Ottawa, Canada
' 

### Nolan, Davis and Associates Ltd. 1992 Environmental Impact from the 

### Use of Sodium 

### Formate at Halifax InternationalAirport. Report prepared for Transport Canada, Ottawa, Canada.

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### Alaska. Porter Dillon Ltd., & Nolan, Davis & Associates Ltd. 1990. "Acid Drainage Treatment Plant Decommissioning Study at Halifax International Airportw, Halifax, NS. Porter Dillon.Lsd. 1985. Environmental Study of the Salmon River Watershed in the Vicinity of the Halifax International 

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### on the Lentic Environment in Interior Alaska. Alaska Department of Transportation and Public Facilities, Fairbanks, Alaska. AK-RD-86-02 Robinson, G.G.C. 1983. Methodology: The Key to Understanding Periphyton. Chap. 30,

. pp 245-251 in R.G. Wetzel (ed.) Periphyton of FreshwaterEcosystems. Proc lst Intent WorkshoponPeriphytonafFreshwater&systems. Vaxjq Sweden, 14-17September 1982. Ruddy9 

### hl. and J. VJirth. 

### 1990. Acute Toxicity of Sodium Formate to Selenastrum capricornutumPrintz Study for Hoechst Celenese by Analytical Biochemical Laboratories Ine, Sax,No I. and R. J. Lewis, sr. 1989. Dangerous Properties of IndustrialMaterials Seventh Edition. Volwne 

## IK Van Nostrand Reinhold, New Yark.

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### C1 Compounds editedby 

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### Analysis. 2nd 

### Ed, Fish. Res. Board Cab Bull. 167: 310

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### a de-icer at Transport Canada Airports. Report to Transport Canada, Transportation Development Centre. Sypher:Mueller International Inc. 1988. City of Ottawa De-Icer Field Trials. Report prepared for the Dept. of Engineering and works, City of Ottawa, Canada. The Airports Authority Group, Airport Facilities Branch. 1986. The Preliminzuy Environmenta1 Impact of Calcium Magnesium Acetate at Canadian Airports, AK-75-09- 215m7636E. Transport Canada. 1988. Environmental Impact Assessment of the Use of Glycol Based Aircraft De-ices at Halifax InternationalAirport. Rep. AK-75-09-156. TransportCanada Airports. 1990. TheEnvironmental Impaci ofUrea onAirport Runways. '.

.. - . . . - .-*,

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### RA 1974. A ~anual-on''Methods foi-~easuring 

### Primary Production in Aquatic Environments. IBP Handbook NO. 12: 225 

### p.

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Wetzel, R.G. 1975. Limnology. W.B. Saundea Company, Toronto: 743 p. Winters, G.R, J. Gidley and H. Hunt. 1984. Environmental Evaluation of Calcium Magnesium Acetate (CMA). California Department of Transportation, Sacramento, 

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