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From: John Mee <jmee@inlandgroup.ca> 

To: Brian Damico/DC/USEPA/US@EPA 

Cc: msvedruzic@inlandgroup.ca, 'Roger Langille' 

 <rlangille@inlandgroup.ca> 

Date: 03/29/2011 09:16 AM 

Subject: Inland comments 

Dear Mr. Damico; 

Further to your recent discussions with my colleague, Mike Svedruzic, 

please find attached Inland's comments. We hope you find these helpful 

in your analysis and we would be pleased to answer any further questions 

you may have or to clarify any of our remarks in this submission. 

Mike is travelling this week, so I'll invite you to contact myself or 

Roger Langille for any questions that come up this week. Once Mike is 

back next week he will also be available for any questions. 

Thank You 

John 

John Mee 

Senior Director, Business Development 

Inland Technologies 

902-895-6346, ext 323 

 (See attached file: Inland Technologies- EPA Information Mar 29 

2011.docx)

Inland Technologies International Limited 

Response to EPA Request for Additional Information Regarding “Plug and Pump” 

Technologies 

Inland appreciates this opportunity to provide the EPA additional information regarding 

“Plug and Pump” technologies and active recovery operations.As a service provider 

whose core business is the collection, management and treatment of spent Aircraft 

Deicing Fluid (ADF) we will provide information and a perspective based on twenty 

years of experience. This includes expertise acquired from over twenty airports in North 

America with both the implementation and operation of both passive and active 

collection methodologies. 

Understanding Active Glycol Recovery 

When we are approached by new clients to implement spent glycol recovery programs 

we understand that every airport is unique. We conduct a detailed on-site analysis and 

develop a program to meet specific needs. While the tools we employ to accomplish 

active recovery are similar from airport to airport the actual approach at each airport is 

customized based on individual requirements. A number of factors have to be evaluated 

and ultimately these influence the components of the spent ADF management program. 

Here are some of the issues we consider when developing the program: 
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1. Defining the environmental objectives 

 Are there prescribed regulatory water quality metrics to be adhered to? 

o Defined as “end of pipe” discharge water quality? 

o Defined as the capture of a target percentage of applied glycol? 

 Will there be a Pilot program implemented to determine feasible long-term 

requirements? 

 What is the compliance timeframe to meet overall program goals? Typically with 

each year of active recovery, collection rates improve with operational 

experience. 

 Are there specific short term objectives that graduate to achieve an overall 

milestone? 

 
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2. Evaluate existing infrastructure, flight operations, weather patterns and 

deicing practices 

 The timing and frequency of deicing, magnitude of deicing events, flight 

schedules and number of locations where deicing occurs will impact the amount 

and type of equipment and recovery methods used. 

 Generally, existing infrastructure can be adapted to be suitable for recovery 

operations. At a minimum, this usually means installation of drain blocking 

devices. 

 Are there inherent space and infrastructure limitations at the airport that must be 

considered when planning/designing new applications to handle deicing runoff?

 Both active and passive glycol recovery methodologies may be able to be 

employed or only one may be feasible.

 Can recovery goals be achieved through on-gate deicing or must deicing take 

place at designated areas? 

 Can strategic areas of the existing tarmac be converted to deicing pads during 

winter weather events? 

 Weather conditions affect the recovery rate of active collection operations. 

Climates where typical events include a high percentage of freezing rain and wet 

snow will dictate different recovery tactics than areas where events are often 

characterized by dry snow. The same type of equipment can be used, but the 

operation of the equipment and the amount of equipment will be adjusted to the 

nature of the climate. 

3. How quickly can a spent ADF collection and management program be 

implemented? 

 Can any of the collection approaches be implemented quickly to achieve some 

measure of environmental protection? 

 

 Typically, block and pump recovery operations can be implemented much more 

quickly than the time it takes to construct new containment systems and/or 

change permanent drainage infrastructure. 

 This can give flexibility to airports to make long term capital improvements. 
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4. Implement an effective collection and management program for ADF 

impacted storm water while minimizing impact on airport operations. 

 All airport stakeholders must understand that the spent ADF collection 

program is as important as any other integral winter operation such as deicing 

and snow removal therefore it must be incorporated into the overall operating 

plan. 

 All airport stakeholders must work cooperatively and coordinate to maximize 

efficiency. 

5. How to maximize efficiency while understanding potential limitations 

 What limitations or restrictions may potentially affect collection objectives? 

Funding, budget implications, equipment availability, coordination and 

integration, etc. 

 Who will actively manage the recovery program? Airport staff, airlines, subcontracted services? 

 Who will assume responsibility for performance? 

 How will performance be measured? 

 What will be the primary focus when collecting? Glycol concentration, focus 

on largest deicing sprayer, allow collection in taxiways, etc. 

 What percentage of glycol will you collect down to before the effort produces 

diminishing returns? The lower the concentration of glycol in the spent ADF, 

the larger volume of water that will be collected. This has storage and 

treatment cost implications. 

 Typically, with active collection the more money spent on equipment, storage 

and overall effort the better the collection rate that can be achieved. There is 

a point however where regardless of the money allocated towards a recovery 

program that there is point where diminishing returns will occur due to 

inherent airport infrastructure limitations and/or coordination issues 

 All airport stakeholders must work cooperatively and coordinate to maximize 

efficiency. 
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Tools that are utilized as part of an Active Spent ADF Collection Program 

The following will highlight key collection technologies that minimize infrastructure 

changes at airports: 

a. Collection Vehicles 

Glycol recovery vehicles and vacuum trucks are a primary component of any active 

spent ADF recovery program. These vehicles are utilized as described in Section 

VII, Section B 1 (a) and (b) of the EPA’s Proposed Rule for Effluent Limitation 

Guidelines and New Source Performance Standards for the Airport Deicing 

Category. 

It is important to note, that both glycol recovery vehicles and vacuum trucks are 

currently in use at many airports in North America and are an integral part of deicing 

operations. These vehicles can be operated safely and do not impede airport or 

aircraft operations with proper coordination and training. In most cases these 

vehicles are essential for winter operations much the same as snow removal 

equipment and other deicing equipment. At airports where environmental 

compliancy related to glycol recovery is critical, airport stakeholders and tenants 

understand that glycol collection efforts must be integrated into the overall winter 

operations plan. 

Typically the implementation of operations using these types of vehicles can occur 

quickly to provide an airport the immediate ability to capture contaminated storm 

water. The specialized recovery vehicles are manufactured by multiple vendors and 

typically can be delivered with three months lead time. 

Both vacuum trucks and glycol recovery vehicles can be purchased, leased or 

provided as part of a service contract. 

Glycol recovery vehicle collection operations virtually always combine the use of 

drain blocks as part of operations. Most Glycol Recovery Vehicle operations employ 

some sort of device in the storm sewer inlets to contain deicing runoff on the apron 

surface until it can be collected. 

Glycol recovery units can be used for on-gate collection or at dedicated deicing 

areas. Vacuum trucks typically are not used for on-gate collection but can be used to 

recover from blocked sumps and drains associated with deicing operations. 

Training, operations plans and safety are absolutely crucial to employing use of 

vacuum trucks and glycol recovery vehicles at airports. 
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In regards to references to the limitations of glycol recovery vehicles and the 

potential operational issues experienced during deicing precipitation events involving 

snow, these issues can be minimized. Collection of snow and slush in the vehicles 

can occur but it really is dependent on the snow removal operations. As much as 

practical, snow should be removed from deicing areas prior to deicing taking place 

and is an integral part of a well managed glycol containment and collection program. 

If the snow is removed prior to deicing on areas such as central deicing pads than 

snow collection in the glycol recovery vehicles is minimized. If snow removal does 

not occur and snow is collected by the recovery vehicle then most machines are 

equipped with a “tilt and dump” feature which allows the operator to quickly evacuate 

the built up material in a designated “pink snow” dump area and return to collection 

operations. Operator training is also important in this process to avoid collecting 

excessive amounts of snow. Typically glycol impacted snow is collected and sent to 

a “pink snow” area by the snow removal contractors so the residual glycol can be 

recovered as needed. 

Glycol concentration ranges of influent can vary greatly as the material is collected 

by glycol recovery vehicles .A range of 0.5 to 30 % concentration is not uncommon 

but many factors influence this. The type of deicing or storm event has a significant 

effect on glycol concentrations in recovered fluid along with many other variables 

.From our experience, with aggressive collection during snow precipitation deicing 

events we can collect fluid as high as 15 to 20% in glycol concentration assuming 

there is no significant waiting period for the vehicles to move into the area and begin 

recovery operations. The highest glycol concentration is seen from frost recovery but 

very small volumes are recovered. During mixed precipitation and freezing rain 

events it is not uncommon to collect spent ADF in concentrations from 1 to 6% glycol 

concentration since so much dilution is occurring with the runoff. 

Based on our experience, by washing the pavement with clean water after initial 

glycol collection this can significantly enhance collection performance. Most glycol 

recovery vehicles are equipped with an onboard freshwater tank and spray heads to 

accomplish this process. This can only be accomplished when outside temperatures 

are above freezing and weather conditions allow. In the past, chemical emulsifiers 

were commonly used in this process, but experience has shown that the emulsifier 

agents don’t really enhance collection performance compared to clean water alone. 

Thus, they are no longer used. 

The use of glycol recovery vehicle water spray systems can also reduce the costs of 

glycol treatment.By washing down glycol impacted pavement after deicing occurs, 

the glycol recovery vehicles can reclaim most of the residual glycol that would 

otherwise wash away with future precipitation events. For airports that have stringent 

guidelines for the release of storm water, by actively reclaiming this additional 
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material this can reduce volumes of spent ADF to be treated to meet storm water 

criteria. 

Operation and maintenance costs for glycol recovery vehicles vary based on the 

frequency of use. This is related to the specific collection requirements of each 

airport and the amount of deicing events which require the glycol recovery 

equipment to be operated. 

Key questions to address when determining costs associated with Glycol Recovery 

Vehicles: 

 Are the glycol recovery vehicles the primary and only means of collection or are 

they used as a secondary method of recovery for frost or deicing pad operations? 

 Where are the units being operated? For example, cold dry climate with typical 

deicing events consisting of dry snow, or northeast climate with frequent ice 

events and wet snow? 

 What type of glycol collection vehicle is being operated? Tow-behind unit or 

single chassis unit? 

In general, the costs for repair and maintenance vary depending on the type of 

recovery vehicle. Based on our experience, the repair and maintenance costs (not 

including fuel and labor) per deicing season range from $3,000 to $10,000 per 

vehicle. Fuel costs can be calculated using the specifications provided by the vehicle 

manufacturer and is dependent on the frequency of use. Labor costs can be 

calculated on a case-by-case basis depending on a variety of airport specific factors 

including whether the operation of the vehicle is performed by airport staff or 

subcontracted to other vendors. 

The typical lifespan of a Glycol Recovery Vehicle varies based on frequency of use 

and type of recovery. Key questions to address: 

 Are the glycol recovery vehicles the primary and only means of collection or are 

they used as a secondary method of recovery for frost or deicing pad operations? 

 Depending on the type of use, frequency of use and based on our experience, a 

glycol recovery vehicle’s lifespan can range from 8 to 15 years. 

 
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b. “Plug and Pump” Technologies 

Inland is currently managing glycol recovery programs at many airports in North 

America. Most of these airports employ some method of “plug and pump” or “block 

and pump” technologies for the recovery of glycol. This has proven to be a very 

effective approach in meeting environmental goals. Low cost drain blockers are 

installed with minimal effort at the beginning of each season or permanently and can 

be used for the duration of the season with minimal effort to maintain and operate 

the devices. 

Ultimately, installation and use of these types of devices require minor infrastructure 

changes. The benefits of utilizing this technology are that airports can quickly 

change and use the existing drainage infrastructure in the near term to 

accommodate deicing without major construction or capital projects. These devices 

allow immediate containment while long term improvement projects such as the 

construction of deicing pads and other containment systems are being developed.

Drain blocking devices include drain inserts, drain plugs, and drain bladders. Fact 

Sheet 33 in the ACRP Report #14 describes these devices and how they are used. 

Single sewer grates are typically blocked by inserts for surface recovery by glycol 

recovery vehicles and trench drains or subsurface drainage systems are usually 

blocked by plugs or bladders for recovery by vacuum trucks. 

Issues related to potential “ponding of deicing stormwater” where drains are blocked 

are in most cases related to drain management and cannot be assumed to be 

directly related to glycol recovery vehicle performance. Many times “ponding” can be 

associated to drainage infrastructure issues or coordination issues. With proper 

procedures and active management, issues related to “ponding” can be minimized 

as to not impede airport operations. It is also important to note that the type of winter 

precipitation events may influence these types of ramp conditions.

c. Portable or Temporary Storage Tanks 

Adequate storage and location of storage tanks is an integral part of any spent ADF 

recovery program. Temporary storage tanks such as “frac” tanks are strategically 

located near areas of deicing to maximize recovery efficiency. These tanks can be 

rented monthly instead of annually to reduce operating expenses.

 
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d. Operational Changes and Coordination 

In order for a spent ADF collection program to be successful, airport stakeholders 

and tenants must understand that glycol collection efforts must be incorporated into 

the overall winter operations plan. Airlines, airport staff, tenants and sub-contractors 

must properly plan and coordinate for the recovery of deicing fluids. Development of 

Standardized Operating Procedures (SOP), training, communication and 

cooperation are essential parts of the overall program. Typically, the longer the 

program is in place efficiency will improve with each deicing season as experience is 

gained. 

Next Steps in the Implementation Process 

Based on the evaluation criteria and consideration of key factors, a complete spent ADF 

or contaminated storm water management plan must be developed before recovery 

operations can begin. The overall program may consist of many but not all of the 

aforementioned considerations. This is developed specifically in response to what is 

feasible for the airport. 

Typical Performance and Expected Results 

A detailed plan, specialized equipment and properly trained staff are a vital part of an 

effective recovery operation. A great deal of consideration and coordination must be put 

into the implementation and management of the program. 

In many cases aggressive glycol recovery operations coupled with plug and pump may 

be more feasible and cost effective in the immediate term than central deicing pads 

constructed specifically for glycol containment. Again, an analysis of the above 

mentioned factors must take place to decide which approach(s) are best suited for a 

specific airport. 

Based on our experiences providing glycol recovery services at airports in North 

America, with the proper allocation of resources, equipment, labor, detailed operating 

plans and proper coordination of all airport stakeholders, a 20% recovery rate (based on 

the EPA methodology of available ADF) is feasible at most airports within one year of 

implementation and without major infrastructure changes to accommodate deicing. This 

assumes however that an experienced service provider is contracted to perform 

services and the spent ADF collection requirement is incorporated into an airport’s 

winter operating procedures. With regards to the question raised whether we effectively 
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meet the 20% collection standard with glycol recovery vehicles, we meet and exceed 

this requirement at all of the airports that we currently operate glycol recovery vehicles. 

To achieve this rate however, we also require drain blockers to be used in conjunction 

with the recovery vehicles. Obviously all of the above mentioned factors have to be 

considered and incorporated for this to hold true. 

In terms of achieving a 40% collection rate (based on the EPA methodology of available 

ADF) at airports, this goal is also feasible. Generally after two to three years of 

operation and modification to our spent ADF recovery programs we are able to achieve 

this performance level. This always requires installation and operation of “plug and 

pump” technologies including drain blockers, glycol recovery vehicles, vacuum trucks, 

supervisory vehicles, dedicated management, adequate storage, detailed operating 

protocols, airport wide cooperation and coordination, and ongoing process 

improvements. This too can be achieved without major infrastructure changes assuming 

the airport does not have inherent limitations that would obscure glycol recovery efforts. 

There is usually a larger allocation of resources required than the 20% capture rate and 

a higher cost. Under the 40% collection scenario it is absolutely crucial to have a 

dedicated staff for glycol recovery, critical that specific deicing procedures are 

developed with spent ADF containment in mind and usually a combination of both active 

and passive collection methodologies are employed to meet this level of performance. 

To accomplish a 60% recovery rate (based on the EPA methodology of available ADF) 

typically infrastructure and operational changes are required. This includes construction 

of deicing pads or use of dedicated deicing areas, specialized containment systems and 

adequate storage for spent ADF. We do achieve 60% recovery rates with “plug and 

pump technologies ” and also most commonly with a combination of both active and 

passive collection approaches. However this was achieved after infrastructure changes, 

many years of experience at that particular airport, by significant operational procedural 

changes for deicing were incorporated as the program expanded, dedicated resources 

for the management program and complete coordination/cooperation of stakeholders. 

Please note that glycol collection rates will vary from event to event during the course of 

any deicing season. The aforementioned collection rates were based on the average 

recovery rate recognized after a final mass balance is calculated at the end of a deicing 

season. In dry non-precipitation events the amount of ADF that can be recovered from 

the tarmac is high. The ADF recovered also tends to have a very high concentration. In 

freezing rain and wet snow events, active glycol recovery operations can be much more 

challenging. The fluid recovered from the tarmac and drains can be more dilute. A larger 

volume of fluid is also collected under these conditions since there is a greater volume 

of water that is captured. For example, east coast airports have a wetter climate and 

typically lower average concentrations and higher volumes of dilute spent ADF. 

Recovery rates typically decrease with freezing rain and mixed precipitation events 
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because of how quickly the deicing fluid dilutes with runoff. Also the concentration of 

collected ADF depends on whether it is possible to recover while deicing is occurring 

and how quickly the fluid can be recovered after the plane moves. It also depends on 

whether the glycol recovery vehicle has to wait for multiple aircraft to be deiced before it 

cleans the area. These factors tend to give variability in the recovery rate, event by 

event, throughout the course of a winter season. 

Case Studies 

Inland has been asked to provide commentary on achievable collection efficiencies 

based on our industry experience. We are providing general information for two large 

hub airports where we have acquired several years of experience implementing and 

managing the spent ADF programs. Specifically we focused on these two programs 

because they include the use of Glycol Recovery Vehicles combined with plug and 

pump operations to collect spent glycol. We are providing information based on actual 

data obtained but will not specify the names of each airport. 

While there will certainly be some slight variation in the collection efficiencies achieved 

based upon an airports geographic location, type of winter precipitation (i.e. snowfall vs. 

mixed precipitation) and airport infrastructure we can provide a case history of what we 

see as realistic and achievable. 

 We have an example of one large hub airport with approximately 1,000 to 1,500 flight 

operations per day and another hub airport with approximately 500 to 1,000 flight 

operations per day. Each airport is located in the Mid-Atlantic region and we have been 

operating at each over the past several years. The larger airport sprays approximately 

175,000 gallons to 200,000 gallons of neat deicing fluid per year while the other airport 

sprays approximately 80,000 gallons to 120,000 gallons of neat fluid. Due to the climate 

in the northeast and Mid-Atlantic region, these airports normally see moderate wet 

snowfall or moderate mixed precipitation events annually. 

At each airport we began by using existing infrastructure to employ a recovery program 

utilizing Glycol Recovery Vehicles combined with various drain blockers and plug and 

pump operations using vacuum trucks. We are contracted to provide all of the 

equipment and labor resources to manage the glycol recovery program. We have 

fulltime employees dedicated to providing the glycol collection and management 

services. In the case of the first large hub airport it has ample room for growth or 

changes to current infrastructure while the second large hub airport has more limited 

options. At the outset neither airport possessed any dedicated infrastructure for 

collecting glycol contaminated storm water runoff or centralized deicing locations. 

Deicing operations were performed primarily on-gate at locations with varying drainage 
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structures and proximity to the storm drainage inlets and our goal was to collect all 

spent ADF that was tested to have glycol concentrations that were 5% concentration or 

higher. The glycol concentrations tested on apron surfaces less than 5% were not a 

primary area of focus in an effort to maximize utilization of resources. 

At the first large hub location we achieved average annual recovery rates ranging from 

a minimum of 35% and maximum in the mid 50% range over the first few years. The 

recovery rate was calculated by taking the total amount of pure glycol collected and 

dividing it by the total amount of available ADF. Please see further below for more 

detailed information on reporting and available ADF. We saw similar collection rates 

during this time frame at the second large hub airport ranging from a minimum of 32% 

to a maximum in the mid 50% range. In each case we achieved these results using 

drain blocking methods for the existing infrastructure with no major changes to deicing 

operations except that the recovery operations were coordinated with airport staff. 

Over the last few years with airport infrastructure improvements, such as apron areas 

modified to be deicing pads, increase in equipment allocation and labor, and operational 

changes to deicing practices we have been able to collect spent ADF with glycol 

concentrations ൒ 1% and subsequently our average annual recovery rate has increased 

and consistently been in the upper 40% to low 60% range at each location. It is 

important to note that we see varying recovery rates per type of weather event. The 

lower range is typically attributed to seasons with more frequent freezing rain events 

while the higher ranges are seen with deicing season with more frequent snow events. 

Freezing rain and mixed precipitation events typically generate a very high volume of 

dilute fluid which must be collected. Resources can become limited while collected very 

large volumes of dilute spent ADF during short periods of time. 

Please note that all recovery rates are reported based on using the EPA methodology of 

Available ADF. This means that the total amount applied of Type I fluid was normalized 

to remove the water content in the ADF solution. 80% of the annual volume of Type I 

was included as available fluid for collection. For Type IV the annual amount applied 

was not normalized (assumed pure by the airport authority) and 10% of the annual Type 

IV volume applied was included as available for collection. The airport authority at each 

airport requires all deicing fluid users to report their usage at a minimum monthly. On 

the collection side, Inland has a detailed reporting and an inventory system to track all 

fluid collected. As fluid is collected and put into each storage tank the fluid is measured 

and adequately circulated to get an average glycol percentage. Handheld 

refractometers are used to obtain glycol concentrations. The glycol content is then 

converted to gallons of pure glycol. Daily, weekly, monthly and annual reports are 

tabulated and reported to each airport authority .These volumes and concentrations are 

verified as the fluid is transferred for recycling operations and a mass balance is also 

calculated on all the concentrated glycol that is produced. 
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Conclusion 

We hope that this information will be useful to the EPA as it completes the evaluation of 

plug and pump technologies. Please do not hesitate to contact us if you require further 

clarification for any of the material we presented or would like to discuss further. Thank 

you for the opportunity to provide this information.