White Papers

AUSTIN’S INCREASED RAINFALL FREQUENCY & PROPOSED CODE CHANGES

Felisa Cantu

ATLAS 14 VOLUME 11

In September 2018, the National Oceanic and Atmospheric Administration (“NOAA”) published a new study, called Atlas 14 Volume 11, that found increased rainfall frequency values across Texas. More specifically, the analysis found that major cities, like Austin and Houston, are more likely to experience a major storm event than previously expected, thus increasing the likelihood of severe flooding (see Figure 1). To prepare for the increased flood risk, the City of Austin has developed proposed changes to the City Code which includes tighter regulations that impact existing and future infrastructure.

THE NEW 100-YEAR STORM

The updated NOAA Atlas 14 results in significant changes to Austin’s rainfall amounts that define the City’s current “100-year storm” event. A 100-year storm is defined as the amount of rain having a one percent chance of being equaled or exceeded in any given year, or 26 percent chance of occurring during a 30-year period.

Based on existing data, the City of Austin defines a 100-year storm event as 10.2 inches of rainfall depth in a 24-hour time period. However, the new Atlas 14 study for Texas shows that this rainfall amount is likely to occur more frequently. NOAA’s Atlas 14 defines the new 100-year storm for the city to be closer to 13 inches of rainfall depth in a 24-hour period, which resembles the current 500-year storm (see Figure 2).

The Atlas 14 study also impacts the existing floodplain zones in the City of Austin. A floodplain is the land which has been or is expected to be covered during a regional flood.  Given Atlas 14’s new historical data, this information indicates that more people and property are at risk of flooding. To account for this increased flood risk, the City of Austin is proposing to rezone the City so that the new 100-year floodplain will be based on the existing 500-year floodplain. These new, larger flood zones will encompass nearly 700 more Central Austin properties than before (see Figure 3).
 

CITY OF AUSTIN CODE PROPOSAL

The City of Austin regulates new development, redevelopment and remodeling in the floodplain. These regulations are meant to protect residents from flooding and reduce public expense in the aftermath of a flood. As a result of the Atlas 14 Study, the City of Austin is proposing to change City code in order to protect the public from flooding.
The proposal has four main components, as outlined below:

  • The proposal uses an interim 100-year floodplain, based on the current FEMA 500-year flood insurance rate map, to regulate development. This change means that the floodplain regulations will apply to more properties. Property owners and businesses in the interim 100-year floodplain would have new restrictions if they want to develop, expand, remodel or improve their properties. The City of Austin estimate that there are approximately 7,200 buildings in the interim 100-year floodplain.
  • The City of Austin includes a new exception that will allow for the administrative approval for redevelopment of a residential building in the floodplain that reduces flood risk. Currently, this often requires approval by the Austin City Council.
  • The proposal recommends expanding an existing exception that allows for a building to encroach on the 100-year floodplain of the Colorado River downstream of Longhorn
    Dam and along Lady Bird Lake to also include Lake Austin and parts of Lake Travis.
  • The proposal recommends an increase in the freeboard requirement for buildings from one foot to two feet.

ADDITIONAL IMPACTS TO CONSIDER

Aside from new City regulations that will impact property owners, the Atlas 14 Study also has additional far-reaching impacts as outlined below:
The proposal has four main components, as outlined below:

  • Flood Insurance – The City of Austin estimates that the number of buildings in the 100-year floodplain could increase from 4,000 to 7, 200. Affected residents who have federally-backed mortgages will eventually have to purchase flood insurance. Those who already have flood insurance will likely see the costs go up. This will affect businesses, too. Residents and business owners in the interim 100-year floodplain should talk to their insurance agent about purchasing flood insurance. Impacts to flood insurance will occur after FEMA approves updated floodplain maps, estimated to occur in 2023 or 2024.
  • Pipes and Ponds – Both public and private storm drain pipes, bridges, detention ponds and other drainage infrastructure will need to be larger to handle the changes associated with updated design requirements for the new storm levels.

UPCOMING PUBLIC HEARINGS

Since September 2018, Austin’s Watershed Protection Department has held meetings to gather input from various stakeholder groups and the public. Following all public hearings, the Austin City Council will consider adopting the proposed regulations.

Interested in attending? The tentative schedule for the remaining public hearings about the proposed regulations are highlighted below:
     • Zoning and Platting Commission – Tuesday, September 17, 2019
    • Planning Commission – Tuesday, September 24, 2019  
    • Austin City Council – Thursday, October 17, 2019

For more information, visit the City of Austin’s official website:
http://austintexas.gov/atlas14
http://austintexas.gov/page/flood-risk-and-atlas-14-details

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Austin White Paper

Austin's increased rainfall frequency  White Paper

STORMWATER, MANAGEMENT AND LID

NANCY SULLINS MPH, LEED AP

STORMWATER - WHAT'S THE BIG DEAL?

TRANSPORTS POLLUTANTS; INCREASES FLOW AND VELOCITIES; IMPACTS DOWNSTREAM

BACKGROUND

The traditional approach to stormwater is to move the water as fast as possible away from businesses and homes. Different means of conveyance include underground systems, concrete lined channels, and open ditching. During a heavy rain event, when the underground infrastructure is at full capacity, roadways often become a secondary form of conveyance. This method of moving stormwater transports terrestrial pollutants into receiving streams, lakes, oceans and other water bodies as well as increased flows and velocities in those water bodies; impacting the water quality and quantity downstream.

PROBLEM

Development within a watershed often results in increased impervious cover which in turn changes the water budget. The increase in volume and rate of runoff from a site as well as the reduction in ground water recharge is directly related to the increase in impervious surface within the watershed. The increased runoff contributes to downstream flooding and reduced groundwater recharge.

SOLUTION

One management strategy that focuses on maintaining pre-development hydrology is low impact development (LID) which includes integrated management practices known as green infrastructure (GI). LID/GI techniques focus on keeping the runoff close to its source and mimicking pre-development hydrology by using infiltration; filtering; storage; evaporation; and detention. The philosophy is to keep the water safely on-site as long as possible, use small distributed features located on-site to mitigate and treat runoff and take advantage of nature. Increased roughness, infiltration, soil modification and on-site storage are LID methods.

Increase in roughness can be accomplished by minimizing impervious cover, disconnecting impervious services, forcing water to pass over vegetated areas, allowing impervious surfaces to drain into natural areas and planting grasses or vegetation in swales to slow velocities. Increase in infiltration and/or on-site storage can be accomplished by the use of pervious paving, native vegetation, green roofs, rain gardens, bioswales, vegetated filter strips, on-site detention and manufactured treatment devices.

LID is supported through federal, state and municipal regulations. For example, the Energy Independence and Security Act of 2007 requires federal development projects with a foot print exceeding 5,000 square feet to maintain or restore the pre-development hydrology of the property. Federal agencies such as the Environmental Protection Agency, Department of Defense, United States General Services, Department of Housing and Urban Development, Federal Emergency Management Agency and the Natural Resources Conservation Service of the Department of Agriculture promote and utilize LID.

An example of a municipality embracing LID is the fact that the City of Los Angeles, California has adopted an ordinance imposing rainwater LID strategies on projects that require building permits. The City requires stormwater runoff to be infiltrated, evapotranspired, captured and used, and treated onsite without allowing any runoff leaving the site for a specified design storm event. States and cities nationwide are adopting LID as an option for managing stormwater runoff. Maryland is one of the first states to implement LID. One Maryland project, Somerset Rain Gardens, realized a significant savings when rain gardens were utilized instead of conventional ponds: $100,000 compared to $400,000 respectively.

PaskUSA possesses several product lines that are great BMP options for LID projects. Below is a listing of some of our products. 

RAINWATER

ParkUSA®’s RainTrooper® is a solution for commercial and residential applications to conserve as much rain as possible to store for future use and to reduce consumption of the limited treated municipal water meeting LID design goals. The RainTrooper is designed with the following components: catchment devices, debris filtration, flush diverters, water storage tanks, pump systems, and water disinfection systems.

The ParkUSA® RainFilter™ is a complete system designed to treat total suspended solids (TSS), debris, and trash from stormwater runoff. It presents a low footprint, consists of a high-density polyethylene (HDPE) tank, an internal stainless-steel filter, and an optimal storage system.

The ParkUSA RainBasin® is a stormwater detention system designed to mitigate the effects of new development and redevelopment on an existing drainage system. In addition, the system can be used for the management of storable and reusable stormwater runoff through ground water recharge or rain harvesting. The RainBasin is a system that affords the designer the opportunity to maximize the developed land by placing the detention easily underground such as under parking lots and roadways with minimal cover, as well as being a LID technique.
 

FLOATABLES

The ParkUSA® FilterBasin™ is a family of stormwater best management practice (BMP) devices designed to fit within common basin structures to provide an economical BMP solution. These basins present an opportunity to pre-filter the stormwater prior to discharging into rain gardens and storm sewers.

BIOFILTRATION

The TreeBasin™ is a biofiltration BMP that can be used in LID applications like stand-alone treatment, pretreatment for infiltration, rainwater harvesting, and detention. The TreeBasin system uses a combination of physical, chemical, and biological processes to remove nutrients, sediments, hydrocarbons, metals, and trash from stormwater. The TreeBasin uses an engineered filtration/absorbing media which presents the ideal characteristics to grow a tree. TreeBasins are highly adaptable for most developments due to a small footprint and shallow elevation. Plant selection allows TreeBasins to be seamlessly integrated into the landscape and adds aesthetic value. Typical TreeBasin applications include parking lots, sidewalks, plazas, and streets.

The NutriBasin™ is a filtration device designed to remove dissolved nutrients (e.g. phosphorus and nitrogen) from stormwater runoff with high removal rates for phosphorous (above 90% removal).  It consists of a concrete vault with top access hatchway; inlet and outlet pipe connections; and an engineered biofiltration media contained in removable cartridges. The NutriBasin™ design allows for easy maintenance. All servicing can be done without entering the vault, which avoids confined space hazards.

The MarshBasin™ is a wetland treatment BMP: an engineered ecosystem that emulates the natural wetland’s ability to improve water quality and is a LID technique. The MarshBasin can be  used in stand-alone applications, pretreatment for infiltration, rainwater harvesting, and detention applications. It uses a combination of physical, chemical, and biological processes to remove nutrients, sediments, hydrocarbons, metals, and trash. The MarshBasin design allows for use from small urban areas to highly developed cities.The MarshBasin is highly adaptable for most developments due to its small footprint and shallow elevation. Typical applications include parking lots, sidewalks, plazas, and streets.

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LID Stormwater White Paper

LID Stormwater White Paper

Oil-filled operational
Equipment and SPCC

NANCY SULLINS MPH, LEED AP

OIL-FILLED OPERATIONAL EQUIPMENT - TRANSFORMERS, WIND TURBINES, ELECTRICAL SWITCHGEARS INCLUDED UNDER SPILL PREVENTION CONTROL AND COUNTERMEASURE (SPCC) RULE.

BACKGROUND

The Oil Pollution Prevention regulation promulgated under the authority of §311 of the Federal Water Pollution Control Act, or Clean Water Act (CWA) sets forth requirements for prevention of,  preparedness for, and response to oil discharges at specific non-transportation related facilities.  To prevent oil from reaching navigable waters or adjoining shorelines, and to contain discharges of oil, the regulation requires these facilities to develop and implement SPCC Plans and establishes procedures, methods, and equipment requirements. The SPCC rule was promulgated in 1973, with significant amendments published in 2002. EPA finalized additional revisions in 2006, 2008, 2009, and 2011.

§112.1 of the SPSS rule establishes the general applicability. The SPCC rule applies to facilities that:

  • Are non-transportation related;
  • Have an aboveground oil storage capacity of more than 1,320 US gallons or a completely buried oil storage capacity greater than 42,000 US gallons; and
  • Could reasonably be expected to discharge oil to navigable waters or adjoining shorelines in quantities that may be harmful.
  • Any container with oil capacity less than 55 US gallons is exempt.

Oil-filled operational equipment is covered by the SPCC rule. Oil-filled operational equipment includes equipment with an oil storage container (or multiple containers) in which the oil is present solely to support the function of the apparatus or the device. Examples of oil-filled operational equipment include, but are not limited to, hydraulic systems, lubricating systems (e.g., those for pumps, compressors and other rotating equipment, including pumpjack lubrication systems), gear boxes, machining coolant systems, heat transfer systems, transformers, circuit breakers, electrical switches, wind turbines, and other systems containing oil solely to enable the operation of the device.

The SPCC rule applies only to facilities that, due to their location, can reasonably be expected to discharge oil as described in §112.1(b). The rule does not define the term “reasonably be expected.”  The owner or operator of each facility must determine the potential for a discharge from his/her facility. According to §112.1(d)(1)(i), this determination must be based solely upon consideration of the geographical and locational aspects of the facility. An owner or operator should consider the location of the facility in relation to a stream, ditch, gully, or storm sewer; the volume of material likely to be spilled; drainage patterns; and soil conditions.

COMPLIANCE

Properly designed, maintained, and operated oil water separators (OWS) may be used as part of a facility drainage system to meet the secondary containment requirements of the rule in §§112.7(c),
112.7(h)(1), 112.8(c)(2), 112.8(c)(11), 112.12(c)(2), and/or 112.12(c)(11). Additionally, §§112.8(b), 112.9(b), and 112.12(b) set forth design specifications for drainage associated with secondary  containment provisions at a facility. Standard gravity and enhanced gravity separators, or other types of OWS, may be used to meet secondary containment requirements. In this application, the separators are expected to have oil and water present in the system when there is an oil discharge or oil-contaminated precipitation runoff within the drainage area.

When OWS is used to meet SPCC requirements, it must be properly operated and maintained to ensure it will perform correctly and as intended under the potential discharge scenarios it is aimed to address. The separator must be constructed to contain oil and prevent an escape of oil from the system prior to cleanup to comply with the secondary containment provision for which it is intended (§112.7(c)).

OWS SIZING

To comply with the general secondary containment requirements of §112.7(c) OWS sizing must address the most likely discharge from any part of the facility and should consider:

  • The drainage area that flows to the separator;
  • The corresponding anticipated flow rate of the drainage system to the separator; and
  • The appropriate capacity of the OWS for oil and for wastewater.

Example: Substation A has one transformer with 187 gallons of mineral oil capacity, one transformer with 420 gallons of mineral oil capacity, and four transformers with 53 gallons of mineral oil capacity each. The area is not diked, as standing water at a facility where high voltage is present is a potential safety hazard. The peak rainfall intensity of 0.6 inch per hour (i) has been determined reasonable design criterion for the area. The drainage area is 8,000 sq. ft.(A) with 100% imperviousness with a run off coefficient of 0.88 (C).

SOLUTION

ParkUSA® offers spill management devices for mitigating oil releases. The following is a sampling. The StormTrooper® HMI, a part of the ParkUSA® StormTrooper® product family, is patented technology that is designed to intercept free fat, oil, grease, TSS, debris and other pollutants found in stormwater. In addition, the HMI system can accommodate spills up to 3,800 gallons. The unit has hydrophobic media and an oil-stop valve to ensure that no oil leaves the separator. A high oil alarm will be activated if the separator oil storage capacity has been met. An optional diverter valve that closes off the effluent line is available.

ParkUSA® OilStop™ Valve (OSV) is a device designed to prevent an environmental catastrophe in the event of an oil or hydrocarbon spill. The patented, yet simple passive design of the OSV is automatic
and requires little maintenance. The OSV can be used to enhance the operation of oil-water separators, inlets basins, and spill containment vaults and manholes. The OSV is an added assurance of non-oily water discharge.


OUR RESPONSIBILITY 

ParkUSA® believes in water technology development to combine efficiency and environmentally friendly products. ParkUSA’s goal is to offer its customers sustainable green solutions that meet todays needs, as well as anticipated changes in regulations.

Contact us for more information and design assistance.

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SPCC Transformers White Paper

SPCC Transformers White Paper

SYSTEMS FOR ACUTE CARE
EMERGENCY PREPAREDNESS

NANCY SULLINS MPH, LEED AP

HEALTH CARE FACILITIES ARE A CRITICAL COMPONENT TO A COMMUNITY’S RECOVERY DURING A DISASTER, AN ACCIDENT OR AN ACT OF TERRORISM. THE WATER SUPPLY FOR A FACILITY COULD BE INTERRUPTED FOR ANY OF THESE INCIDENTS. HEALTH CARE FACILITIES NEED TO BE PREPARED FOR A POTENTIAL LOSS OF THEIR WATER SUPPLY IN ADDITION TO ELECTRICAL POWER AND OTHER INFRASTRUCTURE.

WHERE IS THE AFFF USED?

There is no one set of national standards which establishes requirements for emergency water supplies of health care facilities. However, on June 12, 2002, President Bush signed into law the Public Health Security and Bioterrorism Preparedness and Response Act of 2002. The act requires community water systems, serving populations greater than 3,300, to either prepare or revise an emergency response plan. In developing the plan, community water systems are encouraged to include hospitals.

The Joint Commission on the Accreditation of Healthcare Organizations (JCAHO), an independent non-profit national accreditation organization, has established the standard EM.02.02.09 requiring
hospital emergency operation plans to identify procedures if the hospital cannot be supported by a local community for at least 96 hours relative to water, wastewater disposal, power and heating fuels. Although JCAHO is not a governmental agency, for health care facilities to maintain their accreditation, they must comply with the standard.

The Center for Medicare and Medicaid Services Conditions for Participation/Conditions for Coverage (42 CFR 482.41) requires that health care facilities must include emergency gas and water supply. This requirement has bearing on those health care facilities that treat Medicare and Medicaid recipients.

States and local municipalities may include requirements within their building and/or plumbing codes. 

For example: California has addressed the issue through their building and plumbing codes. SB 1953 (1994), an amendment to the Alfred E. Alquist Hospital Facilities Seismic Safety Act (SB 519 HSSA) of 1973, established five nonstructural performance categories for acute care hospital facilities. These categories include expiration dates with the goal to have all acute care hospital facilities meeting NPC-5, the most stringent category, by 2030. NPC- 5 requires an on-site water supply, holding tanks for wastewater, and fuel supply for 72 hours of emergency operations. Compliance is mandated by 2030, or the facility will be removed from acute care service.

California Plumbing Code Section 614.4.1 states: “For acute care hospital facilities required to meet NPC-5, an on-site water supply of 150 gallons (based on 50 gallons/day/bed for 72 hours) of potable
water per licensed bed shall be provided. The emergency supply shall have fittings to allow for replenishment of the water supply from transportable sources.”

SOLUTION


EMERGENCY POTABLE WATER SYSTEM

To maintain accreditation with Joint Commission on the Accreditation of Healthcare Organizations (JCAHO), an Acute Care Facility needs an emergency potable water supply sufficient to service the
facility for 96 hours. Per California Plumbing Code Section 614.4.1 an Acute Care Facility must supply an on-site water supply of 150 gallons (based on 50 gallons/day/bed for 72 hours) of potable water
per licensed bed.

ParkUSA® offers an emergency potable water system that is integrated into the facility’s potable water system. When there is a disruption in the water service, diverter valves are activated, enabling the backup water supply. The emergency potable water system becomes the facility’s source of potable water for the designed capacity (72 hours or 96 hours). The system comes with an external connector to allow for replenishment of the water supply from transportable sources if the emergency continues past the design period. Potable water storage tanks are utilized to store water onsite in aboveground or belowground configurations. Tank material can consist of: corrugated steel, fiberglass, high density polyethylene and precast concrete.

WASTEWATER HOLDING TANK

The ParkUSA® DeConTank® Series is a holding tank system for the safe containment of sanitary waste or contaminated wastewater. The system is engineered to hold sanitary wastewater when a facility’s wastewater treatment system is not operational or inaccessible. The DeConTank® system also includes an option to intercept and store hazardous wastewater discharged from decontamination rinse showers and isolation activities.

The DeConTank® system features direct bury and aboveground models, sized from 50 to 10,000 gallons. The storage tank is double walled and available in three different materials, precast concrete, fiberglass or stainless steel. The control system includes high level leak detection and a diverter valve system. The diverter valve system is a new innovation that allows for greater utilization for hospital facilities. The hospital personnel can control the shower discharge to either sanitary sewer or the DeConTank® for decontamination activities.

The DeConTank® system can be designed with a pump system to empty the storage tank contents into the sanitary sewer system once the system is operational. If the optional dual system  (Decontamination and Emergency Storage) is chosen, the tank includes a pump port with camlock fitting for remote pump out and a vent with an activated carbon filter.

FUEL TANK WITH SPILL CONTAIMENT

The SuperVault® MH is the first tank to pass the SwRI 95-03 Multi-Hazard test, the toughest national test for aboveground fuel tanks. The SuperVault® MH has been tested for multiple exposure to fires
and other hazards, plus an extended element exposure test. This means that if the SuperVault® MH experiences a hazard, it may be recertified and kept in service rather than having to be replaced.  In addition to SwRI 95-03, the listing includes a 4-hour fire rating. It meets the stringent safety requirements of Uniform Fire Code Appendix Standard A-II-F-1 (UFC 79-7), SwRI Test Procedure 93-01, NFPA 30/30A, and UL 2085 Protected Tank 20-Year transferable warranty. Seismic restraints are part of every tank.  External diking not required by UFC.

SuperVault® MH is offered in two configurations, cylindrical and rectangular. The cylindrical line is available from 250 gallons to 20,000 gallons. The rectangular line is available from 250 gallons to 2,000 gallons. Components that are part of the system include: spill containment basin, shut-off device, overfill alarm, leak sensors, emergency vent. An optional generator for the fuel tank system is available.

OUR RESPONSIBILITY 

ParkUSA® believes in water technology development to combine efficiency and environmentally friendly products. ParkUSA’s goal is to offer its customers sustainable green solutions that meet todays needs, as well as anticipated changes in regulations.

Contact us for more information and design assistance.

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Hospital White Paper

Hospital White Paper

WASTEWATER AND
FIRE FIGHTING FOAM

CHRIS EBERLY. PE

AQUEOUS FIRE FIGHTING FOAM (AFFF) IS A SYNTHETIC FIRE FIGHTING FOAM CONSISTING OF COMBINATIONS OF FLUOROCHEMICAL AND HYDROCARBON SURFACTANTS COMBINED WITH HIGH BOILING POINT SOLVENTS AND WATER. THE SURFACTANTS ALTER THE SURFACE PROPERTIES OF WATER IN SUCH A WAY THAT A THIN AQUEOUS FILM CAN SPREAD ON A HYDROCARBON FUEL EVEN THOUGH THE AQUEOUS FILM IS MORE DENSE THAN THE FUEL.  AFFF SYSTEMS HAVE SUPERIOR FIRE EXTINGUISHING CAPABILITY OF FLAMMABLE OR COMBUSTIBLE LIQUIDS, ESPECIALLY JET FUEL SPILLS.

WHERE IS THE AFFF USED?

AFFF fire suppression systems are typically provided in aircraft hangars. This type of protection is necessary to protect valuable, mission-essential aircraft and hangar facilities. The obstacles to fire suppression in hangars include suppressing fuel fires under wing shadows and rotary-wing aircraft and still protecting the aircraft and its sensitive electronics. AFFF high-expansion foam is effective when discharged overhead. Suppressant foam hits the top of the aircraft and the floor, then flows in a blanket below wing shadows.

AFFF FIRE SUPPRESSION SYSTEMS PROVIDED IN AIRCRAFT HANGERS PROTECT VALUABLE, MISSION-ESSENTIAL AIRCRAFT

ARE THERE DISPOSAL CONCERNS OF AFFF?

A concern of AFFF systems is the discharge of AFFF foam solution. In large volumes, AFFF foam can be harmful to the environment. AFFF solution should not be allowed to flow untreated into the  ecosystem, or into the sewage systems in large quantities. In the event of a fire, the fire suppression system will activate. However, a fire is a very rare event. The primary concern is discharge from
unwanted activations and from periodic testing.

SHOULD AFFF BE RELEASED INTO THE ENVIRONMENT?

AFFF should not be released untreated to the environment. Here is why:

Short Term Consequences

Large volumes of AFFF discharge can negatively impact the environment, as well as produce bad side effects, such as foaming. Because AFFF is biodegradable, the breakdown of AFFF by bacteria consumes oxygen. AFFF can deprive aquatic life of oxygen and cause fish kills.

Long Term Consequences

Fluorochemical surfactants (also referred to as fluorosurfactants) are essential ingredients in AFFF concentrate. No other known class of materials has the capability of producing aqueous solutions of sufficiently low surface tension to permit the formation of an aqueous film on hydrocarbon fuels. This low surface tension allows the aqueous film to spread over and seal the surface of the fuel, extinguishing the flames and preventing the flammable liquids from evaporating. No other type of surfactant can do this as effectively as a fluorosurfactants. Fire fighting agents containing  fluorosurfactants can extinguish flammable liquid fires more quickly using lesser amounts of agent than fire fighting agents not containing fluorosurfactants. A drawback to fluorosurfactants is that
they move with water in aquatic systems and leach through soil. Whereas a readily degradable compound will break down as it leaches through soil, the degradation products of fluorosurfactants
will not. If allowed to soak into the ground, fluorosurfactants may eventually reach groundwater or flow out of the ground into surface water and cause foaming and other undesirable effects.

SHOULD AFFF BE RELEASED INTO THE SANITARY SEWER?

Once the foam-water solution has been contained, the most common method of disposal is to treat it biologically in a wastewater treatment plant (WWTP). The AFFF should be dosed through an oil-water separator and then discharged to a sanitary sewer. A WWTP should be contacted prior to discharge. In most cases it will require a Material Safety Data Sheet for the foam concentrate (contains information on composition, BOD, aquatic toxicity), an estimate of the total volume of foam-water solution to be discharged, and the anticipated timing of the discharge. The WWTP may require foam-water solution to be diluted in advance. The US National Fire Protection Association (NFPA) recommends that the concentration of any foam-water solution in the total volume of WWTP influent should not exceed 1700 parts per million (ppm).

For example, foam-water solution could be discharged at the rate of 7 gallons per minute (gpm) to a 6 million gallon per day WWTP. The difficulties of metering such a low rate of discharge can be overcome by diluting the foam-water solution by 10 or 20 to 1, permitting discharge rates of 70 or 140 gpm respectively.

WHO CAN PROVIDE A AFFF WASTEWATER TREATMENT SYSTEM?

ParkUSA® manufactures a wastewater treatment system that specifically targets AFFF discharge. ParkUSA® has many years of experience with airport Infrastructure & hangers. The ParkUSA® system includes all necessary components from drain to sewer. Here are the components of the ParkUSA® AF3 System.

The AF3 Containment System consists of:

  • Trench Drain
  • Diverter Valve
  • Oil-Water Separator
  • Sample Well
  • AFFF Containment Tank
  • AFFF Containment Controls

HOW DOES IT WORK?

The floor drain system is located in the area protected by fire suppression system, usually a hanger or helipad. The flooring is sloped to the floor drains or trench drain. All fluids that hit the hanger
floor, drain in to the trench drain. Piping connects the trench drain to the automatic diverter valve. The diverter valve assembly has one incoming pipe and two exiting pipes; one directed to the sanitary sewer (normal condition), and another pipe directed to the AFFF containment tank or pond (alarm condition). The diverter valve system can include an automatic control system that will allow the central fire alarm system to activate the diverter valve. The control system will provide valve position status and automatic and manual control.

Normal Condition

Under normal conditions, the flow from spillage and floor wash-down is directed to the oil-water separator. In the separator, all solids and hydrocarbons are separated and retained. The treated effluent flows out of the separator and then through the sample well. The sample well provides an access area to visually inspect and take grab samples of the wastewater effluent. The discharged wastewater is then piped to the sanitary sewer.

Suppression System Activation Condition

Upon the activation of the fire suppression system, a signal is sent to the AF3 management panel. The diverter valve changes position and diverts wastewater flow from the oil-water separator, to the
containment tank where all the fluids are detained.

After-Activation Condition

The AFFF containment tank is eventually emptied by a liquid waste disposal company or can be emptied by managed dosing (pumped at a low flow rate). The dosed flow is directed to the oilwater
separator where solids and hydrocarbons are separated and retained. The treated effluent is discharged to the sanitary sewer.

OUR RESPONSIBILITY 

ParkUSA® believes in water technology development to combine efficiency and environmentally friendly products. ParkUSA’s goal is to offer its customers sustainable green solutions that meet todays needs, as well as anticipated changes in regulations.

Contact us for more information and design assistance.

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AF3 White Paper

AF3 White Paper

Flyer

FoamTrooper Flyer