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HomeMy WebLinkAboutBATCH - Supplemental - 1200 Airport Drive (7)BURLINGTON INTERNATIONAL AIRPORT August 13, 1986 Katherine Vose Act 250 Coordinator District Environmental Commission #4 Ill West Street Essex Junction, Vermont 05452 RE: Burlington International Airport South Burlington, Vermont AIP No. 3-50-0005-08 Dear Ms. Vose: Enclosed are five (5) copies of an application for land use permit for: 1. Relocate, mark and light a portion of Taxiway 'A' 2. Reconstruct, mark and light a portionof Taxiway 'B' For your review. If you have any questions on the above, please contact me. Sincerely, Gerald . DAmico Airport Engineer GWD: tsl Enclosure: 5 sets plans cc: William Szymanski, City Manager, So. Burlington Jane LaFleur, City Planner, So. Burlington Chittenden County Regional Planning Commission Karen Frink, HTA Airport Drive Box 1 South Burlington, Vermont 05401 (802) 863-2874 109FT'W", 'f �4�' ABURLINGTON INTERNATIONAL AIRPORT -71 41t;�Y August 13, 1986 Catherine Rees Agency of Environmental Conservation Department of Water Resources NPDES Permit Section Montpelier, Vermont 05602 Dear Ms. Rees: Enclosed is a application for permit to discharge wastes in conjunction with airport improvements to include: 1. Relocate, mark and light a portion of Taxiway 'A' 2. Reconstruct, mark, and light a portion of Taxiway 'c' If you have any question or require further information, please contact me. Sincerely,, I),," Gerald W. D'Amico Airport Engineer GWD: tsl cc: Katherine Vose, D E C 4 Jane LaFleur, So. Burlington, City Planner CCRPC Karen Frink, HTA Airport Drive Box 1 South Burlington, Vermont 05401 (802)8 63-2874 Sf,.( %-/ 3M(o , Date Received __j By _ Date Application Ccmpleted and Received By By CITY OF SOUTH BURLINGTON APPLICATION FOR SITE PLAN REVIEW 1) NAME, ADDRESS, AND PHONE-NU�IIBER OF: (a) Owner of Record City of Burlington, Vermont (b) Applicant Burlington International Airport (c) Contact Person Gerald W. D'Amico, Airport Engineer 2) PRCX= STREET ADDRESS: Airport Drive, So., Burlington, Vermont 3) PROPOSED USE(S): Aircraft Taxiway - Relocate Taxiway 'A' (approximately 7001 x 75') and Reconstruct a Portion of Taxiway IBI (approximately 2251 -x 75' ) 4) kZE OF PRa= (i.e.,' # of units, floor area, etc.) See above 5) NUMBER OF EMPLOYEES (full & part time) N/A 6) COST ESTIMATES: (a) Buildin ,g s N/A (b) Landscaping $15,750.00 (c) All Other Site Improvements (i.e., curb work) 7) ESTIMATED PROJECT COMPLETION DATE November 1, 1986 8) ESTIMATED AVERAGE DAILY TRAFFIC (in & out) N/A 9) PEAK HOUR(S) OF OPERATION N/A 10) PEAK DAYS OF OPERATION N/A $1,138,250.00 13 j y- — I I � 1786 VATE SI CORPS OF ENGINEERS W6 I BURI-11,16 I ON I,)' (41JADUANULL .1 V11. 63 73 // S W L 5si- x Itim, I ic,,j il 111 T 73-07'3f)" (C L CHES VER) 10' i �30 000 FEE-- 44'30' 7., V c I E R F' Cem al lei' 7- J, 15 ld 1 1. 1 I'A It Y I L� S E It VA T 10 a ny n lie/ pi p" oil 11 1 SL Mi v I "pip Q0K ILI x Chi k-, pA 0 N T t ime Kim v IL ;',I' Qudrrie5 " lb\ rh oil fOO14 ER v 715— J / -- Sub Sta' _q, ��puarry L - 1�, 11YA"00SKI fit 101"o cl s -x I" s > TON qudmes xv r "noun J, Park, e Ao_ r-6 Quarry 'QU I _200 n tvi .0 V ER U 2 to 'I N BU NGT 10 AIRP 720000 I Al I)J FEET vn: a I jjc!r k� A IL A r IV- -7-1 uarry)� South -as g oil CIL ag 'g C, 4925 t -ling Burfin Bui w -ountr s (I. L, n 1,, C 1'. b t V \\ I . 11 —1 * 11 ii , \ / " - 0 1 , 34D A# o, man 27'30" r A �nl 19 k 4923 , Is 0 E 1win 11 E, U I N G T\'. ". 0 U) A^1 Qujiry 429 U, 16 �L;ndinill 4 Ruin 4920 k Q uaiiy 25' It pp 400 sue Ile" 7e.. 0 I I� IV (2) (1 GLIICD�` �LCPF I CRI I A"LAL ARE7�7A---'-, - - , , - -- I =JJ - . L, . r . 13 - CAT-C-4 5A-SIN 11 M 0 M FI El DRPONk&E AREA c G (A AA I F-7 A4 0 H n- ,v I - cr- - 13 a - IL AGENCY OF ENVIRONMENTAL CONSERVATION RTHENT OF WATER RESOURCES APPLICATION FOR PERMIT TO DISCHARGE WASTES Chapter 47 of Title 10 V.S.A. 1. Applicant E3urlinqton International AJ=oZt- Legal Entity 2. Mailing Address Box 1, Airport Drive, Burlinaton, VT 04501 3. Contact -(3erald 1-;. D'Amico Enaineer Telephone 802-863-2874 4. Name of Activity Burlington Inte,rnational Airnort Location South Burlinqton, VT 5. Type of Activity A-Jrnort 6. Nature of Wastes DiSaniLary Industrial Commercial Drainage Other (Describe) 7. Receiving Water Unnamed tributary to Winooski River 8. Status of Discharge r-X7 Proposed 7'Existing (Permit No. 9. Thp applicant hereby applies for a .7 --'Temporary Pollution Permit Emergency Pollution Permit Discharge Permit L-j !Pretreatment Discharge Permit Pretreatment Temporary Pollution Permit to discharge wastes, directly or indirectly, into waters of the State from the above named activity as described in this application, its attached schedule(s), plans and specifications. 10. Application is for Original Permit Permit Renewal If this is for a permit L.:2:j renewal, is original application still valid in all respects ? If not, attach new schedule(s) for major changes. Minor changes may be documented by letter. 11. Enter below, using a separate serial number (S/N) , to identify each independent discharge which will result from the activity described in Item 4. Attach separate schedule for each discharge identified below. S/N 001 Unnamed tributary to Winooski River 004 002 005 003 006 12. Application Fee Enclosed $ — N/A . Date of application August 6, 1986 13. Name of Authorized Representative (See INSTRUCTIONS). Walter E. Houghton Director of Aviation TYPE or PRINT NAME TITLE SI - TNSTRUCTIONS ON REVERSE - FORM WR-82 (Rev. 7/78) STATE OF VERMONT AG( ' OF ENVIRIONY1ENTAL CONSERVATION uLPA.RTMENT OF WATER RESOURCES APPLICATION FOR PERMIT TO DISCHARGE WASTES D SCHEDULE D - DRAINAGE DISCHARGES Date August 6, 1986 D-1 Applicant Burlington International Air�)ort Activity Airport D-2 Dis char7e-S/N nol Designation D-3 Exact location on receiving water (describe and locate on map) unnamed Tril2utary to Winooski River D-4 how are wastes conveyed to receiving water? Via catch basins and underdrain pipe D-5 Type of Dischar,,Te STORM. 4ATER Source and Drainage Area (in acres) : Paved Roads 15 A. Unpaved Roads A. Paved Parking Lots A. Unpaved Parking Lots -A. Roofs A. Natural Terrain 55 A. A. Total 70 A. Design Criteria: Rainfall Intensity in/hr. Rainfall Duration hrs. Return Frequency 5 rs. Coefficient 0-30 Peak Runoff Rate 26 2---Y —CFS Treatment: F-; None Y;Catch Basin or Settling Basin with Submerged Outlet Detention Pond: Area A. Volume CF Depth Ft. Detention Time hrs. and Peak Discharge CFS for design storm Outlet structure(s) CF Max. Depth Rec*,-ar,7e Basin: Area A. Max. Volume Ft. Inches rainfall stored in. Exfiltration Rate CF/hr. Other (describe) GROUNDWATFR AND RETURN FLOWS Source: [:,Fcun,-Iaticn 'Drain F�Curtain Drain L-] Spring ',7 Well , I __� Mine ElQuarry Pond Water Wheel or Turbine Filter Backwash L Discharge: Est. discharge CFS Frequency and duration Pumping required? Contaminants present Treatment: D-6 Additional Information INSTRUCTIONS ON REVERSE FORM WR-82D (7/78) --ay ---DA-TE -,JJEUFCT v SHE T NO -QE- if CHKD. 6Y DATE JO' B No. 4,7A -T( o 11,111 �n +fc-1 'E LIAf:?- -T- iLA '�A 7�- A! L'I �f 7 �171-1 A ��7 I 6:� I -K Ir T-1 T T -T-T Ll T- -1--T--- F HOYLE, TANNER & ASSOCIATES jNC� t)N9,TEr.HNQ'L04Y PARK- ---!LOPI-E)ONDERRY, N -H - 03053 r, . FZe%rm CALCULATIONS- FOR RUNOFF DETERMINATION COMR BY D ATE PAGE PROJ. NO. �77D-7. (Z LOCATION F;7\,) CHEKD.BY DATE. OF ism M:.- as -6 0 60 ig --n Tr I fR fFrT OF CHKD., BY D4TE JOB NO. TO V—c f7" 100- k "ItD- e- ?L,4: -D "nA 74- I Wk( f T-A 411105)-� t J-6c) 112- -71 L HOYLE. TANNEF?- A ASSOCIATES INC � - - ONEJECHNOLOGY PARK--!!--IQI4 DOND ERR Y'. N..H 03053 y qHE I NO 0 E 717� CHKD. BY DATE JOB NO. -T I F-4- 7- -4 LT L4 - -OL" i L -eml -CD- A V- --upl A( c::: om -7�-L t�-: Z4. P- L 4-- - L t --7 X, r LID 10, a c (2; - 1 16� 4. t J-j��J:4E� TL - T-1 -T HOYLE. TANNER 8c ASSOCIA-TES INC. 6NE TECHNOLOGY PARK LONPONDERRY7. N. H 03053 i By_ YQ F DATE 1LUB"Fr-1 _SKEE n CHKZ). BY DATE- JOB NO. L4 -Z�,TA 4-t e., ------ ------ Lt !A Tell 0 e c-IR I le ;Aj T T e-' C' 7_7 7 3�'T.A L ?TA F1 4_6;�,� 01 (3 's C P7.�_- i I FT -- - - ------- HOYLE. TANNER & ASSOCIATES JNC,__� ONE TECHNOLOGY PARK 'LONDONDERRY. N.'H� 03053 I Fnrm C, 1; - I CALCULATIONS FOR RUNOFF DETERMINATION COMR By I D ATE I PAGE PROJ. NO- 3-7-101 - IZ LOCATION 'V!)-T\) - P�aoPt)c-cl) CHEKD. BY -DATE. JOF THROUGH PEArH 2 in, INW 100=1 ON M� MR =m .Mwmm. SIMMS= OVEW L ME millimmommimmus *Mob &*4q nwwl��Nmww now �m ammommow mm�w �Wmw w sm" bll= V — I V�a 6 E 7: i a � i �­ I -- 1 1 7 HKD BY DATE JOB c '41 1c) 17 9 I ZO 7 63 ?- 0 -Z3 T4, -_Cot__ cL5 7� --�.95 _10CC�7 C)3 oo14 00 1 -1, 7— D 2-9 5(-lBTc)TAt— 2 1 , 12-q HOYLE, TANNER & ASSOCIATES INC. ONE TECHNOLOGY PARK - 'LONDONDERRY. N. H 03053 ea --.Q:E� narr7((W im ire-, wn CHK'D._�Y J' B '0. 7:--t�ATE U-)P -7 j -7 t HOYLE, TANNER & ASSOCIATES INC. ONETECHNOLOGY PARK -LONDONDERRY.N H 03053 / ---_—�_-�� - — ''---- �-j�--'--r— _ 'oY's.,AmwE .......... --------- `__-_---.---- mpcIR fRr.w|* 03053' J3 nATF Y D�TE CHKb. B Aki�Al� T--L —A- 11 r) I ... ......... . T- 7-1 HOYLE, TANNER &-ASSQr-LAT-ES-lK -IF v kiFFT Nn J-OB N:O. LD 12 f A U A LI T .TECHNQLQ-Oy P.ARK--!t--LONQQNr)ERRY.. N H, 03053 -914F No Text City of South Burlington 575 DORSET STREET SOUTH BURLINGTON, VERMONT 05403 PLANNER 658-7955 January 31, 1990 John Hamilton Director of Aviation Burlington International Airport 1210 Airport Drive, Box I South Burlington, Vermont 05403 ZONING ADMINISTRATOR 658-7958 Re: Relocate Taxiway "All and Construct Taxiway "G 3", BIA Dear Mr. Hamilton: The South Burlington Planning Commission at its 1/30/90 meeting reviewed the plans for the above referenced project. The Commis- sion determined that the proposed project constitutes minor revisions with no impact to parking, vehicular circulation, or surrounding properties. Therefore, the project does not require site plan approval. Please note that all construction plans and any changes in present use require review by the Planning Department to deter- mine whether their is a need for formal site plan review. If you have any questions, please do not hesitate to contact me. I carel Joec'Weith, City Planner cc: Karen J. Frink, P.E. JW/mcp ill W F A g -7�7 260 3LI-5 C—) -290 ffypV joo 00 PRECISION INSTRUMENT 0 C i-E AR ZONE iBAK-12 0 1 tD 0 320- CL.41 GLIDF SLOPE 50! 1 3W F 994' —.-_q,�EF�RUNU�A�� PL-- � - . . .... ..... 304 ARR -STER/ RIER 5 51 cn 300 90, 75' CL. 36. CL.35 NOTE: PROPOSED WASTE AREAS AS DI'RECTED BY ME% TO EXCEED HEIGHT OF ISTING TERRAIN AND TO BE LEFT LEVEL AND FREE DRAINING E OrL 3 qo EIRL F EE) L 2 EXISTING EASEMENT —L.'MIT OF -(R- E-TOPpING EASEP� . . . . . . ENT U N 01 E V SINGLE FAMILY RESIDENTAL 'J Ix 4 4? 01" Dl;'i'�*)" IAW ULTIMATE ARIA o. oa o.#,o of o' - - - — — - — — - - EX I ST I N G ASEMENT "lo I p ol do d% 4 1194, f- p 'o do, ol 6 J` 01 a cc A 4D p < L-E UIPMENT P�RKIKQ (A2 DIRECTED BY o,,/ OWNER) PETERSON P. YERRACE IJA . 45 A 1. Xl; '14 14. 3E "r'E IRACE AIRP '00oo" La all CAS .0 Proposed Findings of Fact and Conclusions of Law Burlington Airport Taxiway Project Submitted on behalf of: South Burlington Realty Company I. FINDINGS OF FACT Project Description 1. The Applicant has relocated and improved Taxiway ffAff South by building a new taxiway to the east of the prior location (Exhibit A3; Tortolano Cross). The relocation was mandated by Federal Aviation Administration requirements (Exhibit Al.at 3). 2. The changes in Taxiway NAN South required a new drainage system (Exhibit A3 at 3). The new drainage system is shown on Exhibits A4A and A4B, as amended during the October 16 hearing to include changes made in the field. 3. The new drainage system has an outfall adjacent to a parcel of land owned by Munson Earth -Moving Corporation. (Exhibits A4B and S5). This outfall is shown as 'New Outletff in Exhibit A4B (Tortolano Cross). The parties have referred to this outlet as 00utfall No. 3.0 4. The work on Taxiway RAff South has also affected an adjoining drainage system which has an outfall adjacent to the Munson property shown as ffExist 10ff OutletO on Exhibit A4B (Exhibit A4B and S5). The parties have referred to this outlet as NOutfall No. 4.ff 5. Two other Airport drainage systems discharging through outlets designated as ffOutfall No. lff and ffOutfall No. 2ff adjacent to the Munson property will be unaffected by the Taxiway project (Exhibit A21 at 2). 6. As a result of the Taxiway project, the area draining to Outfall No. 3 has been increased from 3.7 acres to 17.0 acres, and the area draining to Outfall No. 4 has decreased from 20.2 acres to 16.1 acres (Exhibit A21 at 2) (Note: these figures do not take into account field differences noted at the hearing]. The total area draining to Outfalls No. 3 and No. 4 has increased to 33.1 acres (an increase of 9.2 acres). Total paved area draining to Outfalls No. 3 and No. 4 has increased by approximately 3.8 acres (Exhibit A21 at 2). -2- 7. Stormwater drains out of Outfalls No. 1, 2, 3 and 4 onto the Munson property, and across the Munson property to a culvert under Williston Road (Exhibit S4). Prior to the Taxiway project, approximately 89% of the peak stormwater discharge onto the Munson property originated from these four outfalls (Exhibit S1 at 3). Criteria I(B) (Waste Disposal) 8. On June 11, 1990, the Agency of Natural Resources, Department of Environmental Conservation issued Discharge Permit #1-0839 (Exhibit A13). Discharge SIN 002 allows discharge of stormwater runoff from the southern section of Taxiway A to an unnamed wetland which discharges to a tributary of Potash Brook (Exhibit A13). 9. The Discharge Permit refers to plans and details prepared by Hoyle, Tanner and Associates and Wiemann-Lamphere Architects, the most recent dated March, 1990, for details of treatment and conveyance of stormwater runoff (Exhibit A13). 10. The plans for the drainage system submitted to the Board (Exhibits A4A and A4B) were revised on April 13, 1990 and June 11, 1990. Todd Sternbach, the Environmental Engineer responsible for reviewing the Discharge Permit application, received and reviewed the April 13 revisions to Exhibits A4A and A4B prior to issuance of the Discharge Permit (Exhibit A26). 11. The version of the plans prior to the April 13, 1990 revisions showed approximately seventeen lateral leaching trenches between Catch Basins #1 and #3, and fifteen lateral leaching trenches between Catch Basins #4 and #6 (Tortolano Cross). The current version of the plans (Exhibits A4A and A4B) shows six such lateral leaching trenches, one at each of Catch Basins #1 through #6. 12. To obtain the Discharge Permit, the Airport's engineers originally filed an application which included a report entitled 'Drainage CalculationsN which has been submitted as Exhibit S18 (Tortolano Cross). The original report included calculations for runoff determinations, on a Form SS-1 supplied by the Agency, which analyzed the drainage area of each catch basin in the system (Exhibit S18). When the April 13, 1990 plan revisions were submitted to Mr. Sternbach, they included a set of hydrologic computations, dated April 16, 1990, which have been retyped and submitted to the Board as Exhibit A7 (Representation of Attorney Ellis). These computations are not on the Agency's Form SS-1 and do not examine each catch basin drainage area; instead, they apply the so-called ORational Methodff to the drainage area for the entire system (Exhibit S1 at 5; Exhibit Al at 6). -3- 13. The Airport's new drainage system collects stormwater from the area of Taxiway A through a series of grass -lined swales and catch basins (Exhibit Al at 4). The stormwater is then carried in underground pipes to Outfall No. 3 (Exhibits A4A and A4B). Some of the pipes are perforated and set in stone -filled trenches, to allow exfiltration of stormwater into the surrounding soil (Exhibit A at 4). 14. Federal Aviation Administration guidelines require airport drainage systems to have adequate peak discharge capacity for a 5-year, 24-hour storm (Exhibit Al at 7). The Airport's engineers have designed the system to handle a 25-year, 24-hour storm (Exhibit Al at 7). 15. The drainage pipe which carries stormwater from Catch Basin #7 to Outfall No. 3 is a 24-inch diameter concrete culvert with a slope of .46% (Exhibit A4B; Tortolano Cross). Prior to the Taxiway project, the pipe exiting at Outfall No. 3 was a twelve -inch corrugated metal pipe (Exhibit A4B). 16. The new concrete pipe at Outfall No. 3 has a capacity of approximately 18 cubic feet per second with no head (no build-up of water above the entrance to the pipe) (Tortolano Cross; Exhibit S18 - pipe capacity calculations). The old metal pipe at Outfall No. 3 had a capacity of approximately 1.4 cubic feet per second with no head (Tortolano Cross; Exhibit S18 - pipe capacity calculations). 17. Both the Airport's engineer and South Burlington Realty's engineer have done a computer simulation, using the TR-20 model developed by the U.S. Soil Conservation Service, to determine the effect of the project on the peak stormwater discharge rate onto the Munson property from all four outfalls (Exhibits A-21, S4 and S15). Both engineers agreed that the TR-20 model is the preferable method for peak discharge analysis (Tortolano Cross; Exhibit S9 at 5). 18. The Airport's TR-20 simulation predicts a net decrease in the rate for a 25-year 24-hour storm from 44.1 cubic feet per second to 34.6 cubic feet per second (Exhibit A21 at 1). South Burlington Realty's TR-20 simulation predicts a net increase for a 25-year, 24-hour storm from 44.1 cubic feet per second to 59.5 cubic feet per second (Exhibit S4 at (i); Exhibit S15 - computer printout). 19. The Airport's simulation shows a decrease in peak discharge at Outfall No. 3 from 12.0 cubic feet per second to 1.3 cubic feet per second (Exhibit A21). South Burlington Realty's simulation shows an increase in peak discharge at Outfall No. 3 from 12 cubic feet per second to 37 cubic feet per second. -4- 20. The parties' computer simulations use essentially the same data set regarding amounts of rainfall, drainage area and types of drainage surface (Exhibits A21, S4 and S15). The simulations differ, however, with respect to calculation of the exfiltration rate from the stone -filled trenches. The exfiltra- tion rate is the rate at which water will flow out of the trench into the surrounding soil. 21. The Airport's calculation of the exfiltration rate, using Darcy's Law, is based upon a number of assumptions, including the permeability of the soil, the hydraulic gradient of the stormwater flow from the exfiltration trenches, and the depth of stormwater in the exfiltration trenches (Exhibit A21 at 39-40). South Burlington Realty's exfiltration rate calcula- tion, using the Green-Ampt formula, also relies on a number of similar assumptions, including the permeability of the soil (Exhibit S14). 22. Neither party did any field testing to verify the assumptions used in the exfiltration calculations (Exhibit S1 at 12; Exhibit Al at 7). 23. The Airport assumed a soil permeability value of 151 feet per day (Exhibit Al at 10). The Airport's value is based upon a classification of two soil samples as ffSPO - poorly graded sand (Exhibit Al at 10). Permeability values for poorly graded sand range between 3 and 300 feet per day (Exhibit A8). 24. During the hearing, the Airport's engineer agreed that the fine grain size of the soil samples indicated a perme- ability value toward the lower end of the SP range (Tortolano Cross). Since the permeability value is used as a multiplication factor in the exfiltration calculations, the effective midpoint of the SP range is 30 feet per day (Tortolano Cross). The appropriate permeability value, based on the testimony of the Airport's expert, is less than 30 feet per day. 25. The Airport assumed a hydraulic gradient of 1.18 in its exfiltration calculations (Exhibit A21 at 39). The maximum possible gradient, for water flowing straight down through the soil, is 1.0 (Exhibit S9; Exhibit S13; Tortolano Cross). 26. The Airport assumed that stormwater would exfiltrate from the entire sidewall surface of the exfiltration trenches (Exhibit A21 at 39). The Airport's engineer testified during the hearing that the stormwater would not rise above the bottom of the outflow pipes from Catch Basins #3 and #6 (Tortolano Cross). According to the linear sections of the exfiltration trenches in Exhibit A21 (pages 45 and 46), this means the stormwater would never rise higher than three feet in the trenches in Infiltration Area A (Catch Basins #1 to #3) or four feet in the trenches in Infiltration Area B (Catch Basins #4 to -5- #6). The stormwater, therefore, will not exfiltrate from the entire 5.5 foot height of the trench sidewalls (Tortolano Cross). 27. The Airport's exfiltration calculations do not assume any clogging of the soil surface or filter fabric which surrounds the stone -filled exfiltration trench (Tortolano Cross). Sediment has been observed in the catch basins in the drainage system (Exhibit S9 at 6). During a peak storm event, water in the catch basins will be turbulent (Tortolano Cross). 28. The Airport's assumptions result in an exfiltration rate from Infiltration Area A of 15.3 cubic feet per second and an exfiltration rate from Infiltration Area B of 13.1 cubic feet per second (Exhibit A21 at 40). 29. South Burlington Realty assumed a soil permeability value of 10 feet per day (Exhibit S9 at 5) in its exfiltration calculations. This value is based upon classification of the soil samples as fine sand (Exhibit S9 at 3; Nelson Cross). Permeability values for fine sand range between 3 and 16 feet per day (Exhibit S12). 30. South Burlington Realty's assumptions result in exfiltration rates ranging from .58 cubic feet per second (trench empty) to .79 cubic feet per second (trench full) for Infiltra- tion Area A and .49 cubic feet per second to .75 cubic feet per second for Infiltration Area B (Exhibit S9 at 4). 31. The Airport's exfiltration rates are higher than South Burlington Realty's exfiltration rates (with the trench full) by a factor of approximately twenty. This difference accounts for the different results in the computer simulation: the Airport predicts a significant decrease in peak discharge, and South Burlington Realty predicts a significant increase. 32. The stormwater from the southern portion of the Airport is eventually discharged into a tributary of Potash Brook (Exhibit A13; Exhibit S1 at 6). The total paved area at the Airport discharging to Potash Brook exceeds 16 acres (Exhibit S4-Appendix 1; Exhibit S15). At the point of discharge, Potash Brook has an upstream watershed area of 36 acres (Exhibit S1 at 6). 33. To obtain a State stormwater discharge permit for a development containing large areas of paved surface discharging into small receiving watersheds, the post -development peak discharge rate cannot exceed the pre -development peak discharge rate (Exhibit S1 at 6). 34. The Airport took a single grab sample from Outfall No. 3 on April 25, 1990 (Exhibit A14 at 2). This sample was -6- analyzed for TKN (Total Kjeldahl Nitrogen), ammonia as nitrogen, ethylene glycol and volatile organics (Exhibit A14 at 2). The sample was taken following a very light rain storm (Exhibit S1 at 9). It is unlikely that this sample accurately represents surface water runoff; it probably reflects background groundwater conditions (Exhibit S1 at 9). 35. The Airport's grab sample showed levels of 2.4 mg./l. for TKN and 1.65 mg./l. for ammonia as nitrogen (Exhibit A16). These levels are significantly elevated above expected levels for groundwater (Exhibit S9 at 7). The levels of TKN and ammonia do not exceed the maximum permissible levels under the State Indirect Discharge Rules, which govern groundwater discharges from large underground septic systems (Exhibit A14 at 3; Exhibit A17). 36. South Burlington Realty recently filed a conditional use application to alter the wetland on the Munson property (Exhibit S6 at 1). The Secretary of the Agency of Natural Resources, in reviewing the application, found that stormwater runoff from the Airport to the Munson property contains petroleum products (oil and grease), ethylene glycol, urea, fuel and sediments (Exhibit S7 at 3). 37. Elevated levels of TKN and ammonia as nitrogen indicate the presence of urea used to deice paved areas at the Airport (Luxenberg Cross). 38. Any increase in the peak discharge rate from Outfalls No. 1 through 4 onto the Munson property will have a significant adverse affect on Munson's ability to make any productive use of the property (Exhibit S1 at 2-3; Exhibit S6 at 1-2). Criterion 9(K) (Impact on Public Facilities) 39. The stormwater from Outfalls No. 1 through 4 eventually drains into a culvert under Williston Road (Exhibit S1 at 4). This culvert is eighteen inches in diameter and has a capacity of approximately 8.8 cubic feet per second (Exhibit S1 at 4). 40. Only South Burlington Realty submitted evidence on the effect the Taxiway project has on the Williston Road culvert. South Burlington Realty's engineer predicts that the peak discharge rate into the Williston Road culvert, for a 25-year, 24-hour storm, will increase from 6.94 cubic feet per second to 7.46 cubic feet per second as a result of the Taxiway project (Exhibit S9 at 5). These peak discharge rates do not include the effect of runoff into the culvert from the storm drain system on Williston Road (Exhibit S4 at 6). 41. The City of South Burlington uses a 25-year, 24-hour storm to evaluate stormwater discharges (Tortolano Cross). -7- II. CONCLUSIONS OF LAW With respect to the Act 250 criteria at issue in this appeal (Criteria I(B) and 9(K)), the burden of proof is on the Applicant. 10 V.S.A. § 6088(a). Pursuant to 10 V.S.A. § 6086(C) and Rule 19, the burden of proof under Criterion 1(B) may be met by the introduction of a stormwater discharge permit issued by the Agency of Natural Resources. A. Criterion 1(B) (Waste DisRosal) 10 V.S.A. § 6086(a)(1)(B) provides that, prior to issuing a permit, the Board must find that: (I]n addition to all other applicable criteria, the development or subdivision will meet any applicable health and environmental conservation regulations regarding the disposal of wastes, and will not involve the injection of waste materials or any harmful or toxic substances into ground water or wells. The applicable regulations are the Vermont Water Quality Standards (effective January 8, 1987) [Note: the Water Quality Standards were amended effective April 27, 1990, but the amend- ments do not affect the provisions cited herein]. Under Section 2-05(B) of the Water Quality Standards, a stormwater discharge is a major discharge if: N1. The area of all roadways and parking areas con- tributing runoff to a stormwater discharge exceeds 1.0 acres and the relationship between the area of the watershed at the point of discharge measured in square miles and the area of all roadways and parking areas measured in acres is less than 3.0. 2. The area of all roadways and parking areas con- tributing runoff to a stormwater discharge exceeds 10.0 acres. The Board concludes that the Airport's stormwater discharge to Potash Brook is a major discharge under both Section 1 and Section 2. Under Section 1, the ratio of receiving watershed area (36 acres or .05625 square miles) to paved area (16 acres) is approximately .0035. Under Section 2-05(C) of the Water Quality Standards, both major and minor discharges are required to Ocontrol peak stormwater flows, where necessary, to prevent any undue adverse effect on the quality of the receiving waters including, but not limited to, causing increased erosion, sedimentation or channel enlargement.ff -8- 10 V.S.A. § 6086(c) provides: The board may by rule allow the acceptance of a permit or permits or approval of any state agency with respect to (1) through (5) of subsection (a) . . . in lieu of evidence by the applicant. The acceptance of such approval, permit or permits shall create a presumption that the application is not detrimental to the public health and welfare with the respect to the specific requirement for which it is accepted. Pursuant to Section 6086(c), the Board has promulgated Rule 19 concerning presumptions. In relevant part, the rule provides that the stormwater discharge permits introduced by the Applicant create presumptions of compliance with respect to waste disposal. Rule 19(E)(1)(e). Rule 19 presumptions may be rebutted. Rule 19(F) provides in relevant part: If a party challenges a presumption, it shall state the reasons therefor and offer evidence at a hearing to support its challenge. If the commission or board concludes, following the completion of its own inquiry or the presentation of a challenging party's witnesses and exhibits, that a preponderance of the evidence shows that undue water pollution . . . is likely to result, the commission or board shall rule that the presumption has been rebutted. Technical non- compliance with the applicable health and water resources and environmental engineering regulations shall be insufficient to rebut the presumption without a showing that the non-compliance will result in, or substantially increases the risk of, undue water pollution . . . . Upon the rebuttal of the presumption, the applicant shall have the burden of proof under the relevant criteria . . . . South Burlington Realty, the party challenging the presump- tion, has demonstrated technical non-compliance with the Agency of Environmental Conservation's requirements for discharge permit applications: the Airport failed to submit the detailed analysis required by the Agency for the revised drainage system plans. Also, the stormwater discharge permit issued by the Agency does not reference the plans for the Taxiway project under consideration by the Board. South Burlington Realty has also proven that the Taxiway project does not satisfy the basic requirements of the Water Quality Standards outlined above. The Board concludes that the Taxiway project will result in significantly increased peak -9- discharges of stormwater onto the Munson property and into Potash Brook. The Board's conclusion is based solely on the evidence submitted by South Burlington Realty, which shows a 35% increase in peak discharge rate onto the Munson property. The Board also concludes that water pollution will likely result from the Airport's non-compliance with the Water Quality Standards, in two ways. First, given the relatively small size of the Potash Brook receiving watershed, the increase in peak rates is likely to cause erosion and downstream sedimentation. Second, the increase in peak discharge on the Munson property constitutes water pollution of the Munson property; the increase will have a significant adverse effect on the usefulness of the property. Based upon the foregoing, the Board concludes that South Burlington Realty has rebutted the Rule 19 presumption. The Board must next weigh the evidence presented by both parties to determine whether the Airport has carried its burden of proof. In reviewing all the evidence, the Board believes that the exfiltration calculation assumptions made by South Burlington Realty are more realistic than those used by the Airport. Most importantly, the Airport's assumption of a permeability value at the upper end of the SP range is not consistent with the soil characteristics of the site; South Burlington Realty's permeability value at the lower end of the SP range and in the middle of the fine sand range makes more sense. The Airport's other exfiltration calculation assumptions run counter to its own statements or violate well -established physical laws. The Airport's calculations make no allowance for clogging of the exfiltration surface. While the Board is unable to determine the precise impact of these factors, it is readily apparent that the exfiltration rates advanced South Burlington Realty are more reliable. In making this determination, the Board has relied on the principle, expressed in prior cases, that the Board should use the most conservative predictions submitted to it where the expert analysis is Nsusceptible to wide variations in assumptions used and interpretations made." Swain Development CorR., Case No. 3WO445-2-EB, Findings of Fact, Conclusions of Law, and Order at 27 (August 10, 1990). South Burlington Realty's predictions of peak discharge rates are more conservative. The Board also notes the vast discrepancy between the design capacity of the outlet at Outfall No. 3 and the Airport's predicted peak discharge. The new 24-inch pipe has a minimum capacity of approximately 18 cubic feet per second; the Airport predicts a peak discharge rate of only 1.3 cubic feet per second. The overcapacity is greater when considered in light of the FAA 5-year storm design standard advanced by the Airport. _10- The abundant overcapacity indicates the Airport's practical expectation of peak discharge rates. Based upon its findings, the Board concludes that the Taxiway project does not satisfy the Vermont Water Quality Standards requirements regarding control of peak stormwater discharge flows. Therefore, the project fails to meet applicable health and environmental conservation department regulations regarding disposal of waters. B. Criterion 9M (Impact on Public Facilities) 10 V.S.A. § 6086(a)(9)(K) provides that: A permit will be granted for the development or subdivision of lands adjacent to governmental and public utility facilities, services, and lands, including, but not limited to, highways. . . . when it is demonstrated that, in addition to all other applicable criteria, the development or subdivision will not unnecessarily or unreasonably endanger the public or quasi -public investment in the facility, service, or lands, pr materially jeopardize or inter- fere with the function, efficiency, or safety of, or the public's use or enjoyment of or access to the facility, service, or lands. (Emphasis added). The Board interprets Criterion 9(K) to call for two separate inquiries with respect to public facilities. First, the Board is to examine whether a proposed project will unnecessarily or unreasonably endanger the public investment in such facilities. Second, the Board is to examine whether a proposed project will materially jeopardize or interfere with (a) the function, efficiency or safety of such facilities, or (b) the public's use or enjoyment of or access to such facilities. The Board's review of Criterion 9(K) in this matter is limited to the effect of the Taxiway project on the function and efficiency of the Williston Road culvert. The only evidence submitted shows that the culvert was near capacity prior to the Taxiway project, and that the project will add significant peak flow. This evidence does not account for all of the stormwater flowing into the culvert. Therefore, the Board cannot determine the function and efficiency of the culvert. The Board has already rejected the Airport's evidence showing a decrease in the peak discharge onto the Munson property. As noted above, the Airport has the burden of proof under Criterion 9(K). Since the Board has no evidence on the function and efficiency of the culvert, and since South Burlington Realty I -11- has demonstrated that increased peak discharge into the culvert will result from the Taxiway project, the Board is unable to conclude that the Taxiway project will not materially interfere with the function and efficiency of the Williston Road culvert. B4/17.1029 I PLANNER 658-7955 City of South Burlington 575 DORSET STREET SOUTH BURLINGTON, VERMONT 05403 April 18, 1990 Craig R. DiGiammarino Assistant District Coordinator 111 West Street Essex Junction, Vermont 05452 Re: Burlington Municipal Airport Taxiway Dear Craig: ZONING ADMINISTRATOR 658-7958 It has been brought to my attention that the taxiway relocation work planned for the Burlington International Airport now in Act 250 review, will increase the storm water runoff to a swampy area to the so-,-.-h of the airport. along Williston Road. This area then drains across Williston Road by the way of a 18 inch pipe. That pipe is t.0o small to carry the flow, especially during a heavy storm. The increase runoff resulting from the planned work will add to the problem. The swampy area is privately owned and the owner has had a hydrology study done on the area. He has plans for developing the area and plans to control the runoff. The airport work may impact his plans. The airport consultant should consider under- ground retention basin or other means of controlling runoff. Thank you for your consideration of this matter. Sincerely, Vj William Skz anski, City Engineer cc: Chip Burr WS /Mcp Zjop, U;Ujia .01 ------------- ;T oz ED 40 O#F ............ qj� jo; 4e va mum '(4jo �ASfER IAND USE PEM T APPLICATION PLEASE DO NOT WRITE IN THIS SPACE NO. Filed: - (Location) (Date) Signature of Coordinator/Com. Member Name, address and phone number of the person seeking this permit? Mr. Thomas W. Schmidt, Airport Manager, Burlington International Airport, Burlington, VT PC Box 2302'Burlington, VT Ph 1-802-863-2874 2. Name, address and phone number of the person to be contacted regarding this application? (Cociplete this only if different from #1 above.) Mr. Milton B. Cram', Dufresne -Henry Engineering Corp. Precision Park, N. Springfield, VT 05150 Ph 1-886-2261 3. Describe the project briefly including its location, type, number of units, lots, etc. Indicate the high and low elevations and outline the tract of land on a county highway map and attaCh the map to this form. Construction' of a new� taxiway on the Burlington International Airport Property (5370' x 75'). Hi.—h elevatic,n 332.7 will in(�Illde D , Low elevation 303.2. Project (, I e ar J n g., P x Pa va on - g ra cl 1 n g.- (I ra J n,� Ze a n d- h 1 t i i m I nou s pavement to complete an existing taxiway system to the threshold of Runway 15 (NW end of instrument runway) 4. Give the address of each of the. applicant's offIces in Vermont, if any. 5. Does the applicant own the tract of land in fee simple? If not, what is the applicant's legal interest in the land, what is the name and address of the owner? Applicant owns in fee most of land except northerly section held by long term easement from the US Government thru US Corp of Engineers (See sheet 2 of the Attached Plans.) When did the applicant acquire ownership or control of the land? 1948 6. If the applicant is not applying as an individual, what kind of legal entity is the applicant filing as, e.g. partnership, corporation, etc., and the date and place the legal entity was formed. (Foreign corpora- tions must supply the date they registered with the Secretary of State for the State of Vermont, and the name of the person upon whom legal processes are to be served.) Filing for the City of Burlington as an authorized representative. 7. a. How many acres are in the entire tract of land? In answering this, include the total acreage of the landowner. 477 acres b . How many acres are directly involved in this project? 32 acres 8. On the back side of this page, write in the names and addresses of all adjoining property owners. If you are not the landowner, list the names and addresses of all property owners adjoining the landowner's tract of land. See attached list of property owners and tax maps. 9. When do you plan to begin this project? July 5, 1978 When will this project be completed? November 1978 10. Attach, when applicable, a copy of:,)restrictive covenants to be used in deeds, restrictive provisions set forth in leas'es, bylaws of condominium associations, or any other restrictions. None -3- 11. Financing: a . Excluding the cost of the land, what is the total cost of the project? $1,400,000 Applicants for subdivisions should.include cost of any improvements, such as roads, ponds, etc. b. How will this project be funded, what financing has been obtained, and what additional financing will be necessary? 90% US Fed. Aviation Administration, 6% State of Vermont, 4% City of Burlington c. If performance bonds will be required of contractors, attach details of the bonds. (100% payment & performance bond required; see attached) 12. What municipal services do you intend to utilize? police; fire protection; solid waste disposal; road maintenance; sewage disposal; water supply; _ other. (explain)- None 13. Will this project involve any of the following: (check those that apply.) a. Fuel.burning equipment c. Incinerators b. Process'equipment d. Air pollution control'equipment NOTE: Complete 14 and 15 below only when instructed to do so by a district coordina- T-or. 14. -1-/we hereby certify and affirm under oath that-1-/we have notified by personal service or by certified mail, return receipt requested, the parties entitled to notice of "/our application pursuant to Title 10 VSA, §60S4, as follows: (Each of the parties get a complete application, including plans): City of South Burlington City Hall S. Burlington, VT 05401 (Name and Address of Municipality) Municipal Planning Commission So. Burlington, VT 05401 (Name and Address of Municipal Planning Conrnissioin�_ PC Box 108 Chittenden County Regional Planning Com. Essex Junction, VT 05452 Name and Address of Regional Planning Commission) - /�' "f (Si gratuy- Thomas W. SchmiV, Airport Mgr. South Burlington Realty Company 366 Dorset Street South Burlington, Vermont 05403 OCT 2 6 1990 (802)863-9039 Downs, Rachlin & Martin October 24, 1990 Mr. William Schroeder, Esq. Downs Rachlin & Martin Post Office Box 190 Burlington, Vermont 05402-0190 Re: Airport Taxiway Dear Bill, Here is a copy of the "flowage rights" document as well as a typed version. You'll need them for you filing on the 31st. Sincerely, Gr o A. Dicovitsky Enclosure Prime Real Estate — Commercial, Residential, Industrial Development Design, Build, Lease, Consulting .01 7 ECUTORS DEED TO AIRPORT FOR FLOWAGE RIGHTS To all Persohd to whom these Presents st 1 come: I Leon D. Latham, Jr. of Burlington in the County'of Chittenden and State of Vermont, executor of the last will and testament of George W. Delorme, late of South Burlington in the County of Chittenden and state of Vermont, deceased, and having in charge the administration of the goods, chattels and estate of said George W. Delorme, under said will, Send Greeting: Whereas, the Honorable Probate Court for the District of Chittenden at a session thereof, holden at the Probate office in Burlington in said District on the 30th day of April, A.D. 1934, on due applications, in writing for that purpose, said application having been duly published according to law, did license and authorize me to sell at auction or private sale all of the real estate of said deceased for the purpose of paying the debts of his estate. And whereas, having previously taken the oath required by law and fulfilled all the requisitions of the Statute, and of the license aforesaid, I have sold part of the same real estate and certain flowage rights in another part of said real estate, to the City of Burlington, a municipal corporation duly chartered, organized and existing under and by virtue of the laws of the State of Vermont and located in said Chittenden County, for the sum of one hundred dollars ($100). Now Know Ye, that pursuant to the license and authority aforesaid and not otherwise, and in consideration of said sum of one hundred dollars ($100), the receipt whereof I do hereby acknowledge, I do by these presents, grant, bargain, sell, convey, and confirm unto the said City of Burlington, its successors and assigns, the following described land and flowage rights in land, in South Burlington, in the County of Chittenden and State of Vermont, the description of said land being as follows, viz: A lot of land on the northeast corner of the land in said South Burlington of which the said George W. Delorme died seised, commencing at a stone marker which marks the intersection of the boundary line of the land in South Burlington owned and used by said City for a municipal airport, with the boundary lines of said land of said Delorme and land of one Soule; thence in a southerly direction for a distance of two hundred feet (200) along the boundary line of the land of said Soule to a point to be marked by a stone marker; thence a distance of three hundred feet (300) in a westerly direction in a straight line parallel to the southern boundary of said Municipal Airport land to a point to be marked by a stone marker; thence northerly in a straight line parallel to the east line of said Delorme property, a distance of two hundred feet (200) to a point to be marked by a stone marker in the southerly line of said Municipal Airport land, and thence easterly along the southerly line of said Municipal Airport land, a distance of three hundred feet (300), to the point of beginning; together with the perpetual right to have surface water from said Municipal Airport land and from the land hereby conveyed, in its natural course or through pipes or ditches, flow over and upon the present marsh land of said Delarme property adjoining the land hereby conveyed, for such distance as such water may cover and to the brook beyond said marsh land, without any right upon the part of the heirs of said Delorme and their assigns to claim any damage EXECUTORS DEE� '"0 AIRPORT FOR FLOWAGE RIGHTS PAGE 2. against the City, its successors or assigh-, on account of such flowage of said surface water upon and over said marsh land, the land hereby conveyed being a part of the real estate and said flowage rights for surface water being an easement or interest in another part of the real estate whereof the said George W. Delorme died seised and possessed in said South Burlington. To Have And To Hold the said premises and said easement and flowage rights in said other premises, with all the privileges and appurtenances thereof, to the said City of Burlington, its successors and assigns, forever, to its and their own use, and I, the said Leon D. Latham Jr., executor as aforesaid, do covenant to and with the said City of Burlington, its successors and assigns, that the said George W. Delorme died seised of the within granted premises and of the land in which the within described easement and flowage rights are granted, and that I am duly authorized by the Court aforesaid to convey said premises and said easement and said flowage rights to the said City of Burlington in manner and form aforesaid; that I have in all things observed the direction of the law and the license aforesaid, in the sale aforesaid, that I will, and my heirs, executors and administrators shall, warrant and defend said premises and said easement and flowage rights against all persons claiming the same or the land in which said easement and flowage rights are hereby granted by, from, or under the said George W. Delorme, or myself as said executor, but against no other person. In Witness Whereof, I hereunto set my hand and seal this 11th day of October, 1934. In Presence of: Theo. E. Hopkins J.H. Macomber Jr. Leon D. Latham Jr, ??? Executor of the last will of George W. Delorme State of Vermont At Burlington in said County this 11th day Chittenden County SS1of October, 1934, Leon D. Latham, Jr. executor of the last will of said George W. Delorme, personally appeared and he acknowledged this instrument by him sealed and subscribed, as such executor, to be his free act and deed. Before me. J.H. Macomber Jr. Notary Public This deed approved as to form and substance this llth day of October 1934. Theo. E. Hopkins, City Attorney Received for Record Oct 12 - 1934 at 10 o'clock a.m. attest., K.F. Tilley, Town Clerk. Chittenden County Re'gional Planning Commission P 0 BOX 108, 58 PEARL STREET ESSEX JUNCTION, VERMONT 05452 - 802 658-3004 June 7, 1978 Burlington International Airport 4CO-331 - 1. The applicant will prbpare a noise impact study With the coopera- tion of the Chittenden County Regional Planning Commission. The study will contain a determination of the airport noise levels including new and numerous on -site sound level measurements; an identification of noise impact problems by comparing the noise level data with commonly accepted thresholds for tolerance in residential neighborhoods; identification of several solutions including the use of natural and man-made noise barriers; evaluation of the solutions based on criteria including technological and financial feasibility; and recommended courses of action. The study will be submitted to the District Environmental Commission # 4 within one year of the date of the Land Use Permit. 2. The applicant will discuss with the County Forester a plan for the location of evergreen vegetation. The applicant will plant a thick stand of evergreen vegetation, especially trees, on airport property in the area southwest of the proposed taxiway. The vegetation will be planted so as to not obstruct the line of sight from the control tower and to not interfere with relevant federal requirements for setback distances from taxiways. Dw/cm Stipulation 4CO-331 by: BURLINGTON INTERNATIONAL AIRPORT BY J"� J'�' Tf�omas Schmidt, -Manager CHITTENDEN COUNTY REGIONAL PLANNING COMMISSION BY _7t _a_R Arthur R. Hogan, r. , Ex-ecutive Director ... Sei,ing the Municipalities of ... Bolton Burlington Charlotte Colchester Essex Junction Essex Town Hinesburg Huntington Jericho Milton Richmond S1. George Shelburne So. Burlington Underhill Westford Williston Winooski I ENVIRONMENTAL SERVICES 75 GREEN MOUNTAIN DRIVE, SOUTH BURLINGTON, VERMONT 05403, TELEPHONE (802) 656-1074 3 May 1990 Mr. Gerald D'Amico Burlington International Airport Airport Drive, Box I South Burlington, VT 05403 Dear Gerald: Burlinston lnic,,navonal Airport M f.'$' 9 01rettor Enclosed are the analytical results for the water sample Aquatec collected from stormwater outfall No. I (the western -most of the two outfalls south of runway No. 1) at 1245 hours on 25 April 1990. This sampling occurred near the end of a morning rainfall. 11he Burlington FregL_j!Kesz reported that 0.16 inches of rain fell on this date. The other stormwater outfall at this location did not have a discharge at the time of sampling. No volatile organics or ethylene glycol were detected above the indicated detection levels. Total Kjeldahl nitrogen (TKN) was found at 2.4 mg/l, and ammonia as nitrogen was found at 1.65 mg/l. As a reference, the Indirect Discharge Rules (January, 1990) have a ground water/surface water standard of 3.0 mg/l for TKN. These rules also have a standard for ammonia that is dependent on the time of year and pH. During winter (November through April), the standard is 1.81 mg/l for pH of 6.5 to 7.5 and decreases to 0.13 mg/l for pH of 9.0. During summer (May through October), the standard is 0.85 mg/1 for pH of 6.5 to 7.S and decreases to 0.08 mg/l for pH of 9.0. 1 have enclosed a page from the rules that lists these standards. Please contact me if you have any questions regarding this information. Sincerely, Roland R. Luxenberg, P.E. RRL/a*mp Enclosures 90057B3MAY90 aquatec ENVOTONMENrAL SERVICES 7q Green Motint.titi liurljmg(,�11. V'1 jA4L%1 Date: 2 May 1990 Aquatec Lab No.: 113741 ETR No.: 21067, Project 90057 Sample Received On: 25 April 1990 Sample Idencification: Burlington International Airport, water sample labeled outfall #1, 4/25/90 at 1245 hours. 97 S F-Ta 1 =71 - . TM_ Volatile Organic Compounds in ug/1 EPA method 8240 MA 2 a t M. 9. F RAM n-T1-A1ZFTM- ITT41TY21-1 Key co the letters used to qualify the results of the analysis: U - The compound was analyzed for J but not detected. The number Is the detection limit for the compound. LCB - Compound was found but at low concentration, comparable to that in the blank. Quantita- tion is not possible. An estimated value. The mass spectrum indicates the presence of the compound, but the calcu- lated result is less than the reliable detection limit for this compound. C - The result has been corrected for the presence of the com- pound in the blank. Quality controls were analyzed with the sample as part of Aquatec's scandard analytical procedures. The results of these are maintained on file at Aquatec. aquatec ENVIRONMENrAL SERViCES 0-0. So. 1111flington, V 1'tA4()J 11-1. 140216"1-1074 Burlington int. Airport Airport Drive, Box #1 So. Burlington, VT 05403 Attention : Mr. Gerald DtAmico Date : 05/02/90 ETR Number ; 21067 Project No.: 90057 No. Samples% 1 Arrived : 04/25/90 P.O. Numbers * page 1 St"ard analyses were performed in accordanea, with Methods for Analysis of Water and Wastes, EPA-600/4/79-020, Test Mothods for Evaluating Solid Waste, $W-846, or Standard Methods for the ExominatIon of Water and WAstowater. ALL resutts are In mg/t unless otherwise noted. Lab No. Sample Description ------- ------------------ 113741 Outfall #1:04/25/90 @1245(Water) Method No. ---------- 350.2 351.3 OR313 Parameter AmMonia-Nitrogen Total KJeldahl Nitrogen Ethylene Glycol Result 2.4 <5.0 < Last Page > Submitted By : /—) AoUatAn T?,,- I INDIRECT DISCHARGE RULES CHAPTER 14: ENvXRONMENTAL PROTECTXON RULES Adopted Dato: I IyA6 n than LAsh, Secretary I kil A�'nnvy of Natural Resources 00partmont of Environmental Conservation 103 South Main Street Waterbury, Vermont 05676 Indirect Discharge Rules Page 26 of 37 An applicant shall demonstrate that an indirect discharge shall not increase the concentration, including background concentration, above the permitting limits at the de$ignated point of compliance either in the ground water or in the stream at 7Q10 stream flows for all of the following parameters: I. Biochemical Oxygen Demand (800) An indirect discharge shall not result in a concentration greater than 2.0 mg/l BOD (five day test). 2. Nitrite (NO,) An indirect discharge shall not result in a concentration greater than 0.02 mg/l N of Nitrite (NOd. 3. Total Kieldahl Nitrogen (TKN) An indirect discharge shall not result in a concentration greater than 3.0 mg/1 N of Total Kjeldahl Nitrogen (TKN). 4. Ammonia (NH3) An indirect discharge shall not result in a concentration of total ammonia NH3 + NH 4 mg/1 as N greater than the following: 211 1 Winter 2 �u=d 6.50 1.81 O.BS 6.75 1.81 0.85 7.00 1.81 0.85 7.25 1.81 0.86 7.50 1.81 0,86 7.76 1.73 0.81 8.00 1.23 0.54 8.25 0.64 0.32 8.50 0.37 0.19 8.76 0.21 0.12 9.00 0.13 0.08 pH of receiving water at point of compliance, as calculated by average hydrogen ion concentration. 2 For the months of November, December, January, February, March and April. 3 For the months of May, Juno, July, August, September, and October. RESOLUTION RELATING TO CITY OF BURLINGTON BOARD OF AIRPORT COMMISSIONERS In the year One Thousand Nine Hundred and Sevety-nine Resolved by the Board of Airport Commissioners of the City of Burlington, as follows: That WHEREAS, the Burlington International Airport has plans for construction of a taxiway at such airport; and WHEREAS, the airport has made application for a Land Use Permit from the District Environmental Commission (D.E.C.); and WHEREAS, one of the questions the D.E.C. has asked is whether construction or development of such taxiway is in conformance with the city's land use plan; and WHEREAS, William Szymanski, City Manager and Steven Page, South Burlington City Planner have reviewed the airport taxiway construction plans and met and discussed the question with Thomas W. Schmidt, Diroctor of Aviation at Burlington International Airport; and WHEREAS, the City of South Burlington plan calls for road improvement at the end of airport drive; and WHEREAS, South Burlington feels that the taxiway construc- tion is in conformance with their city's plan; WHEREAS, it may be necessary to acquire 2 or 3 residential properties to construct such road improvements on the Northwest end of Airport Drive to construct such road improvements; and WHEREAS, federal funds may be available in the future for the airport to acquire 2 or 3 residential properties; and F1 I WHEREAS, the City of South Burlington has no objection to the taxiway construction. NOW, THEREFORE, BE IT RESOLVED that if South Burlington allocates funds for the improvements above referred and if it becomes necessary to acquire the above 2 or 3 residential properties, and Federal funds are available to the airport to acquire such properties, the airport commission will make every reasonable effort to obtain such funding and if such funds are granted for such acquisitions the airport commission will use such funds to acquire such properties. Adopted January 11, 1979 Attest: 6t Clerk 7-4 1 �,Cz-c� 4-,--� (,J kA-d Ci- 76G 4L, L TO: FROM: 1?eCEj(VEj 7990 et 41URRA Y, William Ellis M E M 0 R A N D U M Russell V. Blais Hoyle, Tanner & Assoc. Inc. DATE: May 4, 1990 RE: Burlington International Airport Drainage In order to respond to review comments by Jeffrey Nelson of WH&N dated April 27, 1990, HTA offers the following in the sequence given in the Nelson Memo: Items 1 through 6 are more or less an historical review of past findings, assumptions and opinions regarding drainage conditions associated with the Burlington International Airport and an abutting property downstream of said airport. No comments by HTA are warranted. Items 7. 8 and 9 of the memo acknowledges receipt of additional hydrology computations and disputes some of the parameters used in the methodology. However, the memo appears to accept the peak flow rates resulting from the analysis. Generally, the memo disputes the "unrealistically simplistic" methods used to derive peak flow rates at outlets 3 and 4. The argument becomes mute, however, when one considers the fact that both methods produced essentially the same results. It should be recognized that which -- ever hydrologic method is used it is always only an approximation and when appropriately applied, one method is as valid as another. In Item 9, the memo mentions an increase in peak discharge from outlet No. 3 due to post construction conditions. The writer of the memo expresses concern that this increased run- off would have a detrimental effect to the abutter's property with higher flow velocities causing erosion at the outlet and downstream of the outlet. The proposed construction of a subsurface disposal system for excess run-off as outlined in HTA's analysis would result in no increased discharge to the abutter's property and, overall, would result in a decrease of peak discharge than that which exists presently. Item 10 disputes the volume of water that would be disposed of and or stored in the subsurface system as is proposed by HTA. The main element of disagreement is the permeability of the soils or the rate at which water will flow through the soils. The value used by HTA in the calculation to reflect permeability is well within the range of values given in various technical tables for soils similar to those that exist on the airport property. The method used in computing the performance of the proposed subsurface system is in strict conformance with technical Burlington International Airport Drainage Mr. William Ellis May 4, 1990 Page 2 literature dealing with the subject. As for concerns regarding the "clogging" of the system by sediment carried into it from the surface, HTA addressed this by designing into each catch basin a 5-foot sump to collect sediment that may enter the system from surface run-off. A filter blanket will be installed in the pipe trench to further protect against clogging. Given the above and the fact that similar existing subsurface systems on the airport are performing as designed, HTA is confident that the system planned here will work as expected. That is, it will collect, store and dispose of all excess storm water run-off before it enters the abutter's property. Consequently, no adverse effects to the abutter's property are expected. RVB/sp HTA No. 37720.12(LETTERS) r� t *4 i '14 1j.4 I lo r -cf tj IZ ra