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Dean Mericas, Ph.D. Maris Mangulis, P.E. EPA's Proposed Deicing Rule: What it means to airports. Overview of Topics. Environmental concerns Effluent Limitation Guidelines Case studies in compliance Technical resources Discussion.
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Dean Mericas, Ph.D. Maris Mangulis, P.E. EPA's Proposed Deicing Rule: What it means to airports
Overview of Topics • Environmental concerns • Effluent Limitation Guidelines • Case studies in compliance • Technical resources • Discussion
All Approved Aircraft and Airfield Deicing Materials have Environmental Implications • Aircraft • Biochemical oxygen demand • Toxicity • Odors • Sphaerotilus sp. • Foaming • Pavement • Ammonia toxicity (urea) • Biochemical oxygen demand • Toxicity
BOD5 of Deicing Chemicals Material CBOD 5 Propylene glycol ADF* 730,000 mg/l Ethylene glycol ADF* 400,000 mg/l UCAR PDF 210,000 mg/l E36 PDF 180,000 mg/l AviForm L/50 PDF 40,000 mg/l Raw sewage 200-300 mg/l Typical stormwater 10-40 mg/l * Dow Chemical UCAR™ products
Overview of CWA’s Two-part Approach to Environmental Protection Part 1 • Technology-based effluent limitation guidelines (ELGs) are established nationally by EPA within industry categories. • Set minimum requirements for all facilities in each category. • Permit writer “best professional judgment” may be used if ELGs have not been established. Part 2 (if Part 1 isn’t enough) • Water quality-based effluent limitations are determined based on site-specific conditions and needs.
Effluent Limitation Guidelines EPA has issued ELGs for 56 industries. In establishing ELGs, EPA considers various factors: • The performance of the best pollution control technologies or pollution prevention practices that are available for an industrial category as a whole. • The economic achievability of that technology, which can include considerations of costs, benefits, and the affordability of achieving the reductions in pollutants discharged
Common Misunderstanding about Effluent Limitation Guidelines • ELGs establish performance standards based on “model technologies”. • ELGs DO NOT require implementing the model technologies • Only applies to those facilities “in-scope” of the rule. • Compliance requires achieving equivalent performance by any means available.
Chronology of the ELG for the Airport Deicing Category September 2004 EPA initiated development August 2009 Proposed ELG published for public comment February 2010 Public comment period ended {EPA evaluates/addresses comments} ??????? ???? Final Rule promulgated
Concern:There is no de minimus cut-off for deicer usage Regardless of the volume of deicer usage: • Airports with >10,000 departures required to implement collection. Implications to low-use airports • Minimal benefits • Unjustifiable costs • May be technologically impossible
Concern:New Source Performance Standards ultimately put all in scope airports into 60% collection “New sources” • New runway • “Other types of construction activity” in aircraft movement areas • Left to the permit authority’s discretion Implications • “Hybrid” collection requirements for compliance • Variations in operations • Project planning • 60% may be impossible at small scale deicing airports
Concern:Collection requirements ignore key site-specific conditions and practices • Conservation practices that reduce glycol usage reduce the fraction of “available” ADF • No guidance on method for giving credits • Left to permit writer discretion • Defrosting usage held to the same collection standards as deicing event usage • Much less available for collection
Concern:Model on-site treatment technology is not “best” or necessarily applicable to all deicing runoff Implications: • All treatment needs aren’t represented • Limits apply to all onsite “treatment” with direct discharge to surface waters • Ex: Discharges from stormwater ponds 100,000+ 10,000 1,000 100 Glycol Recycling >12,000 mg/L Anaerobic Fluidized Bed Treatment 1,000 – 30,000 mg/L BOD5 (mg/L) Aerobic Biological Treatment 100 – 2,000 mg/L
Concern: Cost:Benefit analysis may not be accurate Implication: If the analysis is flawed - Expectations will not be achieved - Everybody loses Cost of Compliance Benefits to the Environment =
Concern:Costs are under-estimated Collection costs: • Current ADF collection over-estimated at some airports • Assumes small use airports will be able to obtain inexpensive contract on-call collection/disposal • Example: Ontario, CA for $1,100 / year • Deicing Pad Costs • May be off by $10Ms to $100Ms • Costs of compliance with NSPS for future airfield projects were not included. On-site treatment cost assumptions: • Cost is directly scaled from COD load at Albany facility • Gulfport/Biloxi, MS: $38K for AFB plant incl. all infrastructure
Concern:Benefits are over-estimated Glycol usage estimates: • National usage >50% higher than ACRP estimate Implications: • Impacts from current deicing are over-stated • Reduction in glycol discharges from rule is over-stated
Concern:Benefits are over-estimated Urea discharge assumption: • Assume 100% of applied urea is discharged in stormwater Implications: • Current urea discharges are over-estimated • Reduction in urea discharges from rule is over-stated
Concern:Cost effectiveness of ADF collection requirement is very poor at small airports COD = Chemical oxygen demand SOFP = Snow or freezing precipitation days
Approaches to meeting the proposed ELG Requirements • Boston Logan International Airport • Bangor Air National Guard Base • Gerald R. Ford International Airport
General Edward Lawrence Logan International Airport (Logan) Stormwater discharges to tidal marine waters under NPDES permit Extensive studies show no impairment to Boston Harbor water quality from Logan deicing runoff Currently very limited deicer collection Extremely land-constrained • Large origination/destination airport • New England’s most active airport
Compliance with both ELG and FAA Requirements is Infeasible Due to site-specific conditions (e.g., variable winds), 3 CDF locations would be required to meet 100% throughput per ELG
Compliance with both ELG and FAA Requirements is Infeasible • Two of these locations (N&E Pads) are neither feasible nor cost-effective • Impossible to get necessary permits and approvals • Would require filling 160acres of Boston Harbor ata cost of over $1.55 billion • 3-pad scenario would causeunacceptable aviation safetyand operational problems
Logan – Expanded Juliet Pad • Massport’s only potentially feasible option is expanding existing Juliet “Pad” area. • Would not achieve 100% throughput per ELG • Would cause enormous flight delays at high costs • Would cause unacceptable aviation safety and operational problems
Maine Air National Guard, Bangor International Airport – Apron Retrofit Complete reconstruction of existing KC-135 Tanker Refueling Apron Previous apron had ASR problems that required complete reconstruction MeANG wanted the ability to isolate and collect deicing runoff in the reconstructed apron
MeANG Apron Retrofit • Three separate collection zones • MeANG can isolate/collect 3, 6 or 9 deicing slots
MeANG Apron Retrofit • Contours were developed to establish drainage areas • New inlets collect runoff and send effluent to diversion vaults • Diversion gates are automated to divert runoff remotely
MeANG Apron Deicing Diversion System • Deicing slide gates are remotely controlled from a PC or control panel • External lights indicate zones where deicing is occurring • Runoff is metered to the local POTW for disposal
Gerald R. Ford International Airport • Small hub airport • Moderate user of ADF (70K – 120K gal/yr) • Stormwater discharges to small streams, then to Thornapple River • Options for disposal of deicing runoff limited to a recycling facility 150 miles away • Complaints about odors and attached bacteria resulted in regulatory action
GRR Deicing Collection Approach • Collect runoff at Terminal and Freight Ramps • 3 Mobile Collection Units and 43 Catch Basin Inserts
GRR Deicing Collection Performance • Sphaerotilus remains in creek downstream of GRR • DNRE requiring further controls
Summary • Lots of serious concerns with the proposed ELG • No one knows what the final ELG will look like • Successful glycol runoff collection will be unique to each airport’s situation • Use the tools and past experience out there for guidance • Deicing runoff control requirements are not going to go away
Design resources available to address ELG collection requirements ACRP Report 14 – “Deicing Planning Guidelines and Practices for Stormwater Management Systems” Fact Sheets include design guidance for: Source Reduction Containment / Collection System Components Treatment / Recycling FAA Advisory Circular AC 150/5300-14BDesign of Aircraft Deicing Facilities Provides guidelines for sizing and siting deicing facilities
Both design resources are available on the web ACRP Report 14 http://www.trb.org/news/blurb_detail.asp?ID=10457 AC 150/5300-14B http://www.faa.gov/airports/resources/advisory_circulars/index.cfm/go/document.information/documentNumber/150_5300-14B
Dean Mericas, Ph.D. Dean.Mericas@ch2m.com (512) 453-2468 x233 Maris Mangulis, P.E. Maris.Mangulis@ch2m.com (412) 249-6604