{ '. 
Executive Summary Drainage Swales Large stormwater drainage channels were identified at Addison Airport near the north and south ends of the property and smaller drainage ditches were
also observed along aircraft taxiways near the hangers and maintenance shops. Since most stormwater leaVing the site must flow through these stormwater courses, there is potential for
accumulation of contaminants in the sediments of these basins over time. A slight fuel sheen was observed on the stormwater leaving the site on the west side of the property during this
project. Septic Tanks Four facilities have indicated that they used septic tanks and associated leach fields prior to the installation of sanitary sewer lines. It is believed that the
sanitary sewer system was made available to the airport in the early 1960's, however, an exact date could not be determined. It is likely that the following facilities may have used
septic tank systems since they were all present on the airport property during its early development. 1) Air Traffic Control Tower 2) Cragin Hanger and Maintenance Shop 3) The Six Hanger
and Maintenance Shop 4) 600 Series Hangers 5) Current Omniflight facility across from Ari-Ben Aviator facility 6) Ari-Ben Aviator facility (Old South Terminal Building) 7) Centerline
Aviation Hanger 8) Classic Aviation Hanger and Maintenance Shop ; 9) Jet 1 and 2 10) Mercury Air Hanger 2 (Across from their main FBO Terminal) 11) The A v. Group and Skytech Hangers
(Former qo1liris Hangers) Since mainten.kce activities have been performed in '!lost of these 'facilities for long periods of time, septic tanks pose potential envirQnmental coilcern
because: the floor drains and other drains in these facilities could have beer! connected to the septic tanksystem and used to improperly dispose of unwantect chemicals or waste products.
Fill Areas Fill areas were identified at the north and south ends of the main runway and along the western property boundary in several locationS. One 􀁳􀁵􀁳􀁰􀁥􀁣􀁴􀁾􀁤􀀠fill area was
also identified beneath the current Millionaire facility during the course of the project. While it appears that some fill areas may contain construction debris, the complete contents
of the fill in each area is tinknown. Recommended Actions Based on the limited information currently available, CDM's recommended actions for each of the areas of concern previously
discussed are provided below. AOORPT.EXS COM Camp Dresser &. McKee ES-S 
Executive Summa'Y' /I ADDRPT.EXS Underground and Aboveground Storage Tanks Registration Inconsistencies CDM recommends that the current owners/operators of all the UST systems should
review their current registration information to assure that the information is correct. Ifit is not correct, updated information should be submitted to lNRCC as soon as possible. The
Town should monitor this activity to assure that it is completed correctly. Regulatory Issues Based on the lNRCC files reviewed, the site investigation report for the Texas Pro Air LRST
site is overdue. CDM recommends that the owner/operator of this facility request an extension from lNRCC and complete the report as soon as possible to avoid possible fines. A complete
tank inventory and compliance inspection should be performed on all of the USTs located at the airport to determine the required upgrades needed to bring these systems into compliance
with TNRCC UST regulations. Following completion of the compliance inspection, CDM also recommends that all of the USTs be upgraded to bring these systems into compliance. A Spill Prevention,
Control and Countermeasures (SPCC) Plan should also be developed for the fuel farm area since over 42,000 gallons of fuel is currently stored underground in this area. Release Investigation
All of the fuel farms, other UST/AST tank sYl'tems, hydraUlic lifts and the petroleum pipeline should be investigatl!d to determine the absence or presence of surface and subsurface
soil and groundwater contamination. These areas should be characterized through a 􀁣􀁯􀁭􀁾􀁩􀁮􀁡􀁴􀁩􀁯􀁮􀀠of sljrface; subsurface and/or groundwater sampling and testing to 􀁥􀁾􀁴􀁡􀁢􀁬􀁩􀁓􀁨􀀠curren
t baseline soil and groundwater conditions. At the LRST sites, investigation/remedial action is either ongoing, idle, or groundwater monitoring activities are beirig performed. Regardless
of status, TNRCC files should be reviewed to obtaut most recent so.ils and groundwater characteristics to assist with remediation efforts in these .rreas. Umited baseline sampling and
testing is also recommended in these<areas, 􀁾􀀠. t Since most UST owner/operators will likely attempt to close their facilities under lNRCC Petroleum Storage Tank Risk Rules, the Town
should enst;ll"e that appropriate cleanup standards are required to meet future development and land use plans for the area. The Town may also:want to'consider entering some or all bf
these sites into the TNRCC Voluntary cleanup Program (VCp). once accepted into this program, the TNRCC will issjle a Certificate of Completion that will assist in limiting the property
owner's future liability once satisfactory cleanup COM Camp Dresser & McKee ES·7 
Executive Summary has been completed. The Certificate of Completion is also transferable to future ,}.,/> 􀁾􀁡􀀠property owners. CDM also recommends that a limited metal detection survey
be performed in the area surrounding the pipe observed at the Centerline facility to determine if a UST is located in this area. . Significant FueVChemical Spills and Stained Soil To
effectively assess the surface stains and spill areas identified, a limited soils sampling program should be implemented to develop options for cleanup. Excavation and proper disposal
of the stained areas appears possible since most areas are small. Investigation/cleanup could be performed by the Town or site tenants. An Emergency Spill Response Plan should also be
developed that includes spill control, containment and cleanup procedures that would be implemented in the event of a future spill. This plan would include emergency contact and reporting
numbers and typically will include training on program implementation. Stormwater NPDES Permit The NPDES Permit and SWPPP need to be completed as soon as possible to bring the Airport
into compliance with current federal regulations. Two specific areas of concern that should be; addressed in the SWPPP including airplane washing and exterior waste storage areas. If
necessary, a qualified consultant experienced in stormwater 􀁾􀁡􀁮􀁡􀁧􀁥􀁭􀁥􀁮􀁴practices at airports should be retained to complete this work. . . . . CDM recommends that all4f the
waste materials currently stored outside in 55gallon drums and small Asts should be'characterized, removed from the property and properly dispbsed; Most qf the wastes observed on site
have been in the same location for long periods of time. Following removal of these wastes, any new wastes or chemicals that need to be stored outside should be enclosed in an appropriate
outdoor storage Container that can provide protection from stormwater ronon/runoff and can also provide secondary spill containment. An example of exterior waste/chemical storage cOntainers
recommended for use at Addison Airport are providedfor review in Appendix A. Floor Drains CDM recommends that a driifuage study be completed for all the floor drain systems at the airport
to document where these systems discharge. Ifthe drains in these facilities discharge to 'a,stormwater course, limited testing should be performed on the soils in these'areas to determine
if they have been impacted by the improper disposal of chemical wastes through the years. This study should also be useful in developing the SWPPP for the airport. Specific attention
should be placed on the drainage ditches behind the Cragin hanger and adjacent to the COM Camp Dresser & McKee . e5-S 
Executive Summary Classic Aviation hanger since suspected contaminants were identified in these areas during this project. Storm Drains During limited drainage testing that was performed
by the Town on exterior storm drains, some drains were fOlUld to be connected to the sanitary sewer system instead of the storm sewer system. CDM recommends that the drainage study be
expanded to include all exterior storm drains. This extended drainage study will apsist in verifying if each storm drain is currently connected to the sanitary or storm sewer systems
so that system modifications can be made, as necessary. Drainage Swales Sediments from the stormwater drainage swales identified at the airport should also be analyzed to determine if
significant contaminants have accumulated in these areas over time. Septic Tanks CDM recommends that additional research be performed to effectively locate where septic tanks and leach
fields were located and a limited subsurface sampling and testing program should be completed to determine the absence or presence of subsurface contaminants in these areas. Suspected
FiJI Areas Each of the suspected fill areas should be investigated to determine the makeup of the fill material located in each area, if any. Iffill is identified, the investigation
should be ex;Panded to determine the absence or presence of potential surface and subsurface soil and groundwater contaminants that may be present. These areas shoulq: be characterized
through acombination of surface, subsurface andIor 􀁧􀁲􀁯􀁾􀁤􀁷􀁡􀁴􀁥􀁲sampling and testing to establish current baseline soil and grolUldwater conditions.. " Based on available information
reviewed during this project, it does not appear that a MunicipalSolid Waste Permit needs to be obtained for the fill areas identified at the present time. However, permitting and closure
in accordance with lNRCC regulations maybe required ifwastes other than construction debris are fOlUld during)nvestigation activities or if the dumping of asphalt and other debris continues
iri iri the future. Therefore, CDM recommends that I:i0 further construction debris be used as fill material on this property. These materials should be disposed off-site ina permitted
landfill facility in the future. COM Camp Dresser & McKee ES·SADORPT.EXS 
Robert M. Owens, PoE.ij: Environmental Mobile: (912) 1la9-7956 Email: tmowens56@yahQo.C>:IM.Innovations, L.L.C. Engineering and Envlronmontal Solutions 2300 Hlghland Village Road P.
O. BOl( 270801 Sulle320A Flower Mound, Tex3s .. 75021Highland Village. Tox:as 75067 Telephone; (972; 966·2523 Fax: (972) 9M-{j742 
Addison Airport Action Plan Addressing Potential Environmental Concerns Identified in the February 1998 Phase 1 Environmental Site Assessment Report Preparedfor: Town ofAddison 16801
Westgrove Drive Addison, Texas 75001 Prepared by: Addison Airport ofTexas, Inc. 4505 Claire Chennault Dallas, Texas 75248 May 19. 1998 
Addison Airport Action Plan Addressing Potential Environmental Concerns Identified in the February 1998 Pbase 1Environmental Site Assessment Report Table ofContents 1. Introduction 1.1
Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Priority Schedule ..................................................
1 1.3 Work Plan Organization ............................................ 3 2. Areas ofConcem .,." .............. , .... , .. ,.,', .. "."., .. , ... ,., ...... 4 2,1 Fuel Storage and
Dispensing Operations ., .. ,., ... ,., ..... , ... " ....... 4 2.1.1 Registration and Compliance With Technical Standards ",.,., ...... 4 2.1.2 Leaking Petroleum Storage Tank Corrective
Actions ............... 10 2.1.3 Spill Prevention, Control, and Countermeasures Plan (SPCC) ....... 13 2.2 Stonn Water Management ............ , ...... , ...... " ...... " ..... 13 2.2.1
NPDESPermiiActivities .......................... , ..... , .... 14 2.2.2 SWPPP Activities . ............................... , ..... , .... 14 2.2.3 Drainage Swales . ..........................
, ................ 16 2.3 Emergency Spill Response Plan ................ , , .... ,.............. 17 2.4 Surface Spills and Stained Soil ................................. , .... 17 2.4.1
Priority 1 Sites . ........................... , ................. 18 2.4.2 Priority 2 Sites . ............. , ............................... 19 2.4.3 Priority 3 Sites . ............................
................. 23 2.5 Suspected Fill Material ............................................ 34 2.6 Suspect Septic Tanks .... , ........................................ 35 2.6.1 Suspected
Septic Tanks on Ground Lease Facilities ................ 36 2.6.2 Suspected Septic Tanks on Non-Ground Lease Facilities ............ 36 2.7 Other Areas .... , ....... , ....... ,.,.,
... ".', .. ,., .. , .... , ... , .. ' 38 2.7.1 Hydraulic Lifts ................ , .... ,',." .......... , ..... , .. 38 2.7.2 Petroleum Pipeline ........... , ..... , ... , .. , ....
, .. , ..... , ... 39 3. Costs Summarized ........................... , ..................... ,., .. 40 
1. Introduction In March 1998, the Town ofAddison issued a Phase I Environmental Site Assessment (ESA) Report for the Addison Airport. The ESA Report presented the findings ofan environmental
site assessment conducted by Camp Dresser & McKee Inc.(CDM). The objectives ofthe environmental site assessment were to identifY potential environmental concerns on the airport property
that could affect future management plans and assess the current environmental condition of the airport. The ESA utilized a combination of records research, interviews, and site inspections
to meet its stated objectives. No scientific or engineering sampling and analyses were performed during the ESA. The ESA Report identified operational activities and facilities and areas
ofthe airport property that present potential environmental concerns. In most cases, the basis for the potential environmental concern was listed. Upon receipt ofthe ESA Report, Addison
Airport ofTexas, Inc. (AATI) began evaluating the potential environmental concerns identified in the ESA Report. AATI has not independently evaluated whether the concerns identified
in the CDM report are valid. On March 19, 1998, the Town ofAddison issued a letter directing AATI to prepare an Action Plan to address the potential environmental concerns contained
in the report within 60 days. Accordingly in response to the Town ofAddison's request, AATI submits this Action Plan. 1.1 Purpose The purpose ofthe Action Plan is to provide an action
plan to address the issues identified in the ESA Report. The Action Plan includes evaluation of potential environmental concerns identified in the ESA Report and provides a summary ofthe
actions conducted to date. The Action Plan also details proposals for further assessment ofareas ofenvironmental concern identified in the ESA Report. In preparing and submitting this
Action Plan, however, AATi does not admit liabili for these environmental concerns. The implementation ofthis Action Plan is 􀁾􀁮ent u ro nations from the Addison Airport Upkeep Budget
in addition to the cooperation of the Town ofA Ison and Airport tenants 1.2 Priority Schedule The initial step in addressing any potential environmental concern is to evaluate the degree
and extent of the concern. The American Society for Testing and Materials (ASTM) Standard Practice for Environmental Site Assessments (E 1527-94) was used by CDM and provides the industry's
standard for conducting ESA. According to the ASTM standard, al I recognized Addison Airport Plan ofAction Page 1 prepanxl byAddison Ailport ofTe.YOs. Inc. 
environmental conditions should be reported. These include the presence or likely presence of any hazardous substances or petroleum products on the property that indicate an existing
release, past release, or material threat ofa release. The term is not intended to include de minimis conditions that generally do not present a material risk of harm to public health
or the environment and that generally would not be the subject ofenforceable action if brought to the attention of appropriate governmental agencies. AA TI evaluated the potential environmental
concerns identified in the ESA Report in order to establish a priority-based plan of action. AA TI has met with and had numerous discussions with Town ofAddison representatives to discuss
the planned approach ofthe Action Plan. In addition, Town ofAddison representatives have been present at several ofAATI's meeting with various tenants on the airport. Meetings and conversations
have occurred between AATI and the Texas Natural Resource Conservation Commission (TNRCC) and United States Environmental Protection Agency (USEPA). The evaluation ofthe potential environmental
concerns included additional research on the concerns and further site inspections. AATI was joined with Town of Addison representatives during the additional site inspection associated
with the surface spills and stained soils identified in the ESA Report. Based on the results ofthe evaluation, it is apparent that the potential environmental concerns identified in
the ESA Report vary greatly. A prioritized plan was developed in order to effectively address the potential impacts ofthe potential environmental concerns. The potential environmental
concerns identified in the ESA Report were prioritized into the following categories: l-l5} Priority 1: Imminent threat to human health or the environment or under direct /􀁾􀀠supervision
ofa regulatory agency; l.-\f Priority 2: Potential threat to the environment; requires further assessment and possible 􀁾􀀠remediation; and Priority 3: No apparent threat to the environment;
requires 􀁦􀁵􀁲􀁴􀁾􀀻􀀬􀀺􀀺􀁳􀀴􀁥􀁾􀁶􀁥􀁲􀁩􀁾1 ? Activities have been implemented and remedies pursued for all Priority 1 items. Plans havt been developed and cost estimated prepared
for the Priority 2 items. A request to increase the Addison Airport Upkeep budget for this fiscal year has been submitted in order to implement these plans. Plans and cost estimates
are being finalized for the Priority 3 items. These items will be included in the Airport Upkeep budget request for next fiscal year. Addison Airport Plan 0/Action Page 2 prepared by
Addison Airporr o/TeXils, 1m:. 
1.3 Action Plan Organization The potential environmental concerns identified in the ESA Report have been broken down into the following six primary areas ofconcern: Fuel Storage and
Dispensing Operations Storm Water Management Emergency Spill Response Plan Surface Spills and Stained Soil Suspected Fill Areas Suspected Septic Tanks Any potential environmental concern
that was identified and did not fit into one ofthese areas was covered in the final section (Other Areas), Each ofthe following sections contains the prioritized work plan for the particular
area ofconcern. The estimated costs associated with the activities conducted and planned to be conducted to address the potential environmental concerns identified in the ESA Report
are included in Section 3. These costs cover the activities needed in order to assess whether the potential environmental concerns are environmental problems, The estimated costs are
only those that have or will be incurred in connection with the upkeep ofthe airport, They do not not include any costs incurred by the tenants, These costs do not cover any remediation
ofany site. Should the assessment activities indicate that remediation is needed, a work plan and cost estimate will be prepared. Addison Airport Plan ofAction Page 3 prepared by Addison
A,rport o/Te:ws. Inc, 
2. Areas of Concern 2.1 Fuel Storage and Dispensing Operations According to the February 1998 Phase 1 Environmental Site Assessment performed by CDM, there are nine active registered
Petroleum Underground Storage Tank Facilities located on the Addison Airport property. Two facilities are operated by the Town ofAddison and are located at the Service Center and Central
Fire Station. The remaining active facilities are used by various operators for aircraft fuel storage and dispensing operations on the airport. In addition to the active facilities,
two former UST facilities are located on the Addison Airport property. One ofthe facilities formerly provided fuel for emergency backup at the FAA air traffic control tower (ATCT). The
other is identified as the former Texas Pro Air facility and provided storage and dispensing operations for aircraft on the airport. Three primary areas of concern were identified in
the Phase 1 report. The first area is registration and compliance with technical standards. The second second is corrective actions for Leaking Petroleum Storage Tank (LPST) sites. The
third involves the spill prevention and countermeasures plan. As previously discussed, the plan for addressing the environmental concerns identified in the Phase 1 report has been prioritized
based on degree of potential impact. All activities associated with the fuel farm area are Priority 1 items. The items listed in the fuel farm area are being resolved under the direct
supervision of the TNRCC and EPA. ---􀀮􀀮􀀮􀀭􀀭􀀢􀀢􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀮􀁾􀀭􀀭􀀭..􀀭􀀭􀁾􀀮􀀭􀀮􀀭􀀭􀀭􀁾􀀭􀀭􀀧.......􀀭􀀭􀀭􀀭􀁾􀀭2.1.1. Registration and Compliance With Technical Standards
Chapter 334, Title 30 ofthe Texas Administrative Code requires that all underground storage tank (UST) systems be registered and meet certain technical standards concerning construction
and operation. The technical standards requirements are phased in over a period oftime based on specific conditions at the UST system. Each ofthe existing UST systems at the Addison
Airport must meet these technical standards. Additional technical standards for system integrity testing and cathodic protection, and revised release detection methods are required to
be met by December 22, 1998. AA TI representatives have met with the fueling operators on the Addison Airport on several occasions. AATI informed each operator of the applicable state
UST requirements and Town of Addison Fuel Permit requirements. Addison Airport Plan oJActhm Page 4 prepared by Addison Airporl oJTe:ms, Inc. 
On April 21,1998, the TNRCC conducted a compliance inspection ofthe active fuel storage and dispensing operations at the Addison Airport. This inspection did not include the two Town
of Addison facilities. The purpose ofthe inspection was to evaluate the facilities' compliance with the applicable rules and regulations regarding these technical standards. According
to the TNRCC, an inspection report will be sent to each ofthe fueling operators during May. The report will include any deficiencies encountered and actions required to meet the standards.
The report will require that each operator resolve any deficiencies within 30 days. Revised registration forms were completed by each ofthe operators as part ofthe inspection. Facility
No. 22; Multi User Fuel Farm; Operators -Mercury Air Center, Millennium Jet Center, and Ari Ben Aviator The UST systems located in Facility No. 22 are operated by Mercury Air Center,
Millennium Jet Center, and Ari Ben Aviator under either a Public or Non-Public Aircraft Fuels Dispensing Permit issued by the Town ofAddison. According to the Phase 1 report, the registration
for this facility needs to be updated. On April 21,1998, the TNRCC conducted a compliance inspection ofthe current fuel storage and dispensing operations at this facility. The inspection
was to evaluate the facilities' compliance with applicable rules and regulations regarding fuel storage and dispensing. Revised registration forms were prepared by Equitable Leasing
on behalf ofthe operators as part ofthe inspection and have been forwarded to the Town ofAddison for approval prior to submittal to the TNRCC. According to the TNRCC, an inspection report
will be sent to each ofthe operators during May. The report will include any deficiencies encountered and actions required to meet the standards. The report will require that each operator
resolve any deficiencies within 30 days. AATI Action Follow-up with each operator after the receipt of the TNRCC compliance inspection report. Monitor each operator's progress towards
towards making any upgrades to the UST systems that were identified from the TNRCC inspection. Follow-up with each operator for their plan ofaction to meet the December 22, 1998 technical
standards requirements. Monitor the implementation ofthis plan. Facility No. 3036; Operator -Million Air The UST systems located in Facility No. 3036 are operated by Million Air under
a Public Aircraft Fuels Dispensing Permit issued by the Town ofAddison. According to the Phase 1 report, the registration for this facility needs to be updated. On April A,Mison Airport
Plan ofAction Page 5 preppred by Addison Airport ofTe.ms, Inc. 
21, 1998, the TNRCC conducted a compliance inspection of the current fuel storage and dispensing operations at this facility. The inspection was to evaluate the facilities' compliance
with applicable rules and regulations regarding fuel storage and dispensing. Revised registration forms were completed by Millionaire as part ofthe inspection. According to the TNRCC,
an inspection report will be sent to Million Air during May. The report will include any deficiencies encountered and actions required to meet the standards. The report will require
that each operator resolve any deficiencies within 30 days. AATIAction Follow-up with Million Air after the receipt ofthe TNRCC compliance inspection report. Monitor Million Air's progress
towards making any upgrades to the UST systems that were identified from the TNRCC inspection. Follow-up with Million Air for their plan of action to meet the December 22, 1998 technical
standards requirements. Monitor the implementation ofthis plan. Facility No. 14509; Operator -E.U.A. Air Support (Formerly Mission Properties Company) The UST systems located in Facility
No. 14509 are operated by E.UA Air Support (E.UA) under a Public Aircraft Fuels Dispensing Permit issued by the Town ofAddison. According to the Phase 1 report, the registration for
this facility needs to be updated. On April 21, 1998, the TNRCC conducted a compliance inspection ofthe current fuel storage and dispensing operations at this facility. The inspection
was to evaluate the facilities' compliance with applicable rules and regulations regarding fuel storage and dispensing. Revised registration forms were completed by E.UA. as part ofthe
inspection. According to the TNRCC, an inspection report will be sent to E.UA. during May. The report will include any deficiencies encountered and actions required to meet the standards.
The report will require that each operator resolve any deficiencies within 30 days. AATIAction Follow-up with E.UA. after the receipt ofthe TNRCC compliance inspection report. Monitor
E.UA.'s progress towards making any other upgrades to the UST systems that were identified from the TNRCC inspection. Follow-up with E.UA. for their plan of action to meet the December
22, 1998 technical standards requirements. Monitor the implementation ofthis plan. Addi.son Ailporr Plan of..J.clion Page 6 prepared byAddison Ai/parr ofTe.'W.s, IT/c. 
Facility No. 15460; Operator -R. Stern FBO Limited The UST systems located in Facility No. 15460 are operated by R Stern FBO Limited under a Public Aircraft Fuels Dispensing Permit issued
by the Town of Addison. According to the Phase 1 report, the registration for this facility needs to be updated. On April 21, 1998, the TNRCC conducted a compliance inspection ofthe
current fuel storage and dispensing operations at this facility. The inspection was to evaluate the facilities' compliance with applicable rules and regulations regarding fuel storage
and dispensing. Revised registration forms were completed by Stern as part ofthe inspection. According to the TNR CC, an inspection report will be sent to Stern during May. The report
will include any deficiencies encountered and actions required to meet the standards. The report wil! require that each operator resolve any deficiencies within 30 days. AATIAction Follow-up
with R Stern after the receipt ofthe TNRCC compliance inspection report. Monitor Stem's progress towards making any upgrades to the UST systems that were identified from the TNRCC inspection.
Follow-up with R Stern for their plan of action to meet the December 22, 1998 technical standards requirements. Monitor the implementation ofthis plan. Facility No. 27123; Operator -Town
of Addison (Central Fire Station) According to TNRCC registration records, the Town ofAddison operates one 2,000 gallon diesel tank and one 10,000 gallon gasoline tank at this facility.
The Phase 1 report indicates that the registration for this facility is correct. Since recordsfrom the Town ofAddison concerning this facility have not been received, this cannot be verified. No further action is planned for this site. AATIAction Follow-up with the Town ofAddison
for their plan ofaction to meet the December 22, 1998 technical standards requirements. Monitor the implementation ofthis plan. Facility No. 35843; Operator -FAA (ATCT) TNRCC files indicate
that one USTwas used to supply fuel for the emergency power backup system and removed from this location in 1989. The UST was permanently removed from service. The documents indicate
that soil sampling during the removal ofthe UST did not encounter any elevated levels ofpetroleum hydrocarbons. The UST facility was granted clean Addison Airport Plan ojAction Page
7 prepored byAddison Airport afTe.:cas, Inc. 
closure by the TNRCC. No further action is planned for this site. Facility No. 36935; Operator -Town of Addison (Service Center) According to TNRCC registration records, the Town ofAddison
operates one 10,000 gallon gasoline, one 6,000 gallon gasoline, one 1,000 gallon diesel, one 550 gallon used oil, and one tank of unknown size and contents at this facility. The Phase
I report indicates that the registration for this facility needs to be corrected. Since records from the To\Vl1 of Addison concerning this facility have not been received, this cannot
be verified. AA Tl Action Request that the Town of Addison review the current registration data on this facility. Work with the To\Vl1 ofAddison for the submittal of a corrected registration
form, ifneeded. Follow-up with the Town ofAddison for their plan ofaction to meet the December 22, 1998 technical standards requirements. Monitor the implementation ofthis plan. Facility
No. 44612; Operator -R. Stern FRO Limited The UST systems located in Facility No. 44612 44612 are operated by R Stern FBO Limited under a Public Aircraft Fuels Dispensing Permit issued
by the Town ofAddison. According to the Phase 1 report, the registration for this facility needs to be updated. On April 21, 1998, the TNRCC conducted a compliance inspection ofthe current
fuel storage and dispensing operations at this facility. The inspection was to evaluate the facilities' compliance with applicable rules and regulations regarding fuel storage and dispensing.
Revised registration forms were completed by Stern as part of the inspection. According to the TNRCC, an inspection report will be sent to Stern during May. The report will include any
deficiencies encountered and actions required to meet the standards. The report will require that each operator resolve any deficiencies within 30 days. AATlAction Follow-up with R Stern
after the receipt ofthe TNRCC compliance inspection report. Monitor Stern's progress towards making any upgrades to the UST systems that were identified from the TNRCC inspection. Follow-up
with R Stern for their plan ofaction to meet the December 22, 1998 technical standards requirements. Monitor the implementation ofthis plan. Ad&sOf/Airport Plan ofAcUon Page 8 prepared
by Addiscl} Airport ofT(ixas, Inc. 
Facility No. 50235; Operator -Addison Aircraft Storage (Cherry Air) The UST systems located in Facility No. 50235 are operated by Addison Aircraft Storage (Cherry Air), under a Public
Aircraft Fuels Dispensing Permit issued by the Town ofAddison. According to the Phase I report, the registration for this facility needs to be updated. On April 21, 1998, the TNRCC conducted
a compliance inspection ofthe current fuel storage and dispensing operations at this facility. The inspection was to evaluate the facilities' compliance with applicable rules and regulations
regarding fuel storage and dispensing. Revised registration forms were completed by Cherry Air as part ofthe inspection. According to the TNRCC, an inspection report will be sent to
Cherry Air during May. The report will include any deficiencies encountered and actions required to meet the standards. The report will require that each operator resolve any deficiencies
within 30 days. AATIAction Follow-up with Cherry Air after the receipt ofthe TNRCC compliance inspection report. Monitor Cherry Air's progress towards making any upgrades to the UST
systems that were identified from the TNRCC inspection. Follow-up with Cherry Air for their plan of action to meet the December 22, 1998 technical standards requirements. Monitor the
implementation ofthis plan. Facility No. 63865; Operator -Mercury Air Center The UST systems located in Facility No. 63865 are operated by Equitable Leasing. Equitable Leasing leases
the UST systems to Mercury Air Center under a Public Aircraft Fuels Dispensing Permit issued by the Town ofAddison. According to the Phase 1 report, the registration for this facility
needs to be updated. On April 21, 1998, the TNRCC conducted a compliance inspection ofthe current fuel storage and dispensing operations at this facility. The inspection was to evaluate
the facilities' compliance with applicable rules and regulations regarding fuel storage and dispensing. Revised registration forms were prepared by Equitable Leasing on behalf ofMercury
Air as part ofthe inspection and have been forwarded to the Town ofAddison for approval prior to submittal to the TNRCC. According to the TNRCC, an inspection report will be sent to
Mercury Air during May. The report will include any deficiencies encountered and actions required to meet the standards. The report will require that each operator resolve any deficiencies
within 30 days. Addison Airport Plan ofAction Page 9 prepared byAddisan Airport ofTe.rus, IIIC, 
AATIAction Follow-up with Mercury after the receipt of the TNRCC compliance inspection report. Monitor Mercury Air's progress towards making any upgrades to the UST systems that were
identified from the TNRCC inspection. Follow-up \'lith Mercury for their plan of action to meet the December 22, 1998 technical standards requirements. Monitor the implementation ofthis
plan. 2.1.2. Leaking Petroleum Storage Tank Corrective Actions Subchapter D ofChapter 334, Title 30 of the Texas Administrative Code sets forth the requirements for reporting and corrective
action associated \\lith any release from an UST system. The Phase I report identified five LPST sites located on the Addison Airport. One additional LPST site has been added since the
Phase 1 report was prepared. The following table summarizes the LPST sites located at the Addison Airport. Facility Name Facility Address Facility lDNo. LPST No. Addison Airport 4788
Roscoe Turner Road Dallas, Texas 75248 22 91471 Texas Pro Air 15407 Addison Road Addison, Texas Texas 75248 20294 92419 Million Air 15407 Addison Road Addison, Texas 75248 30356 98890
Jet Way 15407 Addison Road Addison, Texas 75248 44612 110033 Central Fire Station 4798 Airport Parkway Addison, Texas 75244 27123 111949 Cherry Air 15407 Addison Road Addison, Texas
75248 50235 112934 AATI representatives met \\lith the listed responsible parties (RP) for the LPST sites, except the Central Fire Station, on several occasions. AA II discussed the
RP's plan to meet the TNRCC requirements \\lith each RP. The proposal was made to conduct a single assessment ofall ofthe fuel farms in order to full -.. ofeach RP. Since all ofthe s
did not agree, each RP will address his own LPST site with the TNRCC. ' Addison Airport Plan ofAclicn Page 10 prepared byAddison Airport 0fTe.wli.lnc. 
-( /r􀁾􀀧􀀠 Each of the RPs is currently working with the TNRCC. One site has received closure from the TNRCC. Three sites have reports, plans, and/or requests pending with the TNRCC.
The field activities have been completed and a report is expected to be submitted to the TNRCC within the next few weeks on the final site. LPST No. 91471 -Addison Airport Addison Airport
of Texas has conducted several phases of assessment activities at the site in order to define the extent of petroleum hydrocarbons in the subsurface. At the time of the Phase 1 report,
TNRCC had requested additional assessment activities to support portions ofthe Plan A Risk Based Site Assessment submitted in 1997. AA TI has conducted the additional assessment activities
and submitted an addendum to the risk based site assessment on May 1, 1998. The additional activities included additional soil analyses and groundwater analyses. In addition to the results,
the submittal to the TNRCC contained the proposed plan ofaction for the site. The proposed plan ofaction includes the collection of additional soil samples in the area of highest petroleum
contamination at the facility. In addition, groundwater monitoring was proposed. AATIActioll Work with the TNRCC on the proposed activities for the site. Conduct the activities that
are approved by the TNRCC. LPST No. 92419 -Texas Pro Air Texas Pro Air formerly operated fuel storage and dispensing operations from this facility. Texas Pro Air went bankrupt in the
1988 time frame and apparently emptied the tanks oftheir contents. Shortly thereafter the tanks floated out ofthe tankpit and breached the surface ofthe ground. During 1988, five USTs
and associated impacted fill material were removed from this facility. Soil samples coIlected following the UST removal indicated slightly elevated levels of petroleum hydrocarbons remaining
in the subsurface. The TNRCC assigned LPST No. 92419 to this facility. TNRCC requested that information concerning the UST closures be submitted and a site assessment be conducted at
the site .•Although AA Tl denies that it is the responsible party 􀁾for this site, it is addressing the site with the TNRCC-Additional data was generated from the former Texas Pro Air
site during the recent risk based assessment conducted by Cherry Air on LPST No. 112934. These data revealed very low to nondetectable levels ofpetroleum hydrocarbons in the subsurface
at the former Texas Pro Air site. AATI has been in discussions with the TNRCC on this site. A report containing the available data from the 1988 UST closures and data collected from
the recent Cherry Air investigation will be submitted within two weeks. Addisoll Airport Plan ofAction Page 11 prepared by ..l.ddison Airport o/Texas. Inc. 
AATIActioll Conduct additional activities if required by the TNRCC. LPST No. 98890 -Million Air In 1991, an overfill ofone UST prompted the TNRCC to issue LPST No. 98890 for this facility.
Million Air was directed by the TNRCC to perform a site assessment to determine the extent of petroleum contamination. Million Air conducted the required site assessment activities and
submitted the result to TNRCC. On March 25, 1998, Million Air received a closure letter from TNRCC stating that no further actions are required for this LPST site. AATI Actioll None
LPST No. 110033 -Jet Way Jet Way formerly operated this facility. A site assessment was performed by R. Stem FBO Limited prior to bringing the UST systems back into service after a long
period without use. Elevated levels ofpetroleum hydrocarbons were encountered in the soil samples collected from the north end ofthe tank farm. The TNRCC assigned LPST Number 110033
to the site based on these soil sample results. On May 1, 1998, Stern sent a letter to the TNRCC summarizing the activities performed at the site. The letter also questioned the assignment
of the original LPST number and requested closure ofthe LPST site. AATIActioll Follow-up with Stern when a response is received from the TNRCC. If additional activities are required,
monitor the activities performed at the site and Stern's progress in meeting the TNRCC requirements. LPST No. 111949 -Central Fire Station The Central Fire Station has been assigned
LPST No. 111949 which identifies the Town of Addison as the responsible party. During the installation of spill and overfill protection equipment at this facility, a leak was discovered
in a product line. Free product was encountered in the tankpit. According to Mr. Mark Acevedo ofthe Town of Addison, the site assessment has been completed. The site is in the final
quarter of groundwater monitoring. The Town of Addison intends to request closure ofthis LPST site at the end ofthe groundwater monitoring. 􀁾􀀮􀀠AddisOTl Airport Pia" ofAction Page
12 prepared by Addison AilporI ofTe:ws, I"c. 
AATIAction Collect the necessary information from the Town ofAddison in order to monitor the activities performed at the site and their progress in meeting the TNRCC requirements. LPST
No. 112934 -Addison Aircraft Storage (Cherry Air) In November 1997, Cherry Air experienced an overfill of product from one of the UST systems. The spilled material was contained and
the impacted area was excavated. The TNRCC assigned LPST Number 112934 to this site. Subsequently, another surface spill from an overfill occurred. TNRCC directed Cherry Air to perform
a risk based site assessment to determine the extent of petroleum contamination from these incidents. In April 1998, Cherry Air initiated a risk based site assessment on the site. The
laboratory results have been received. The risk based assessment report is expected to be submitted to the TNRCC by the end of May. AATI and their environmental consultants have been
provided with preliminary data from the site assessment. Based on the review of the preliminary results, the efforts undertaken by Cherry Air meet the requirements of the risk based
site assessment. AATIAction Collect necessary information from Cherry Air to evaluate if the site is being assessed and remediated in accordance with TNRCC requirements. Monitor the
progress ofthese activities. 2.1.3. Spill Prevetltion, Control, alld Coulltermeasures (SPCC) Plan The preparation of the SPCC plan for the entire fuel farm area is underway. The SPCC
Plan is expected to be submitted to the appropriate regulatory agency within the next three weeks. The SPCC Plan covers all of the USTs located in the tank farm area. The SPCC Plan will
be incorporated in the airport's overali emergency spi\I response plan as detailed in that section. 2.2 Storm Water Management According to the February 1998 Phase I Environmental Site
Assessment performed by CDM, the general National Pollutant Discharge Elimination System (NPDES) Permit ofthe Addison Airport had expired and a notice of intent to obtain a new multi-sector
permit had been sent to the USEPA. In addition, several areas of potential concerns were identified in the ESA Report that were possibly impacting storm water management. On March 12,
1998, AAII received the new NPDES Permit for the Addison Airport. The industrial tenants (37) have submitted Notices ofIntent to the USEP A for coverage under the ..lddison Airport Plan
OjA(:Iion Page 13 prepared by Addi.wn Airport afTe.W$, Inc. 
Addison Airport NPDES Permit. The Addison Airport is the permitee and each of the tenants will be co-permitees. The activities associated with the storm water management at the Addison
Airport are categorized into NPDES Permit Activities and Storm Water Pollution Prevention Plan (SWPPP) Activities. Activities in both categories are Priority I items and are underway.
Many of the activities have been completed. The ESA Report also identified the drainage swales at the airport to be areas of potential environmental concerns. According to CDM, there
is a potential for the accumulation of contaminants in the sediments ofthese storm water basins since most storm water leaving the site must flow through them. The evaluation ofthe drainage
swales is a Priority 3 item and is included at the end of this section. 2.2.1 NPDES Permit Activities On March 12, 1998, AA TI received the new NPDES Permit (TXR05E625) for the Addison
Airport. The multi-sector general permit requires certain storm water pollution prevention and control measures, possible monitoring and reporting, and annual inspections. Thirty-seven
industrial tenants at the airport have submitted Notices ofIntent (NOI) to the USEPA for coverage under the Addison Airport NPDES Permit. The initial NOr contained incorrect information
concerning the Standard Industrial Codes (SIC) for the tenants. The tenants have submitted revised NOI and most have received their individual NPDES Number. The tenant NPDES Permits
relate back to the Addison Airport permit. The Addison Airport is the permitee and each ofthe tenants are co-permitees. AA TI has had several meetings with the tenants to discuss the
storm water management issues and plans. Meetings have been designed to educate the tenants to the requirements ofthe NPDES permits and to collect and disseminate operational information.
All ofthe activities associated with the NPDES Permit are Priority I items. t1-'I-J--a/lo-l-7 The estimated cost to complete the Priority I items is $ 15,000. _ J.0􀁪􀀮􀀮􀁊􀁾􀀠. 2.2.2
SWPPP Activities A Storm Water Pollution Prevention Plan (SWPPP) is required under the conditions ofthe multisector general permit. In January 1998, AA TI implemented the SWPPP for the
Addison Airport. AATI has contracted with EA Engineering, Science and Technology to evaluate the SWPPP and expand on the plan. EA is a professional environmental consulting firm with
strong capabilities in the area of SWPPP. They have prepared several SWPPP for airports including ones for Love Addison A.irport Plan olAe/ion Page 14 prepared byAddison Airport o/Texas,
Inc .. 
Field and Red Bird Airport in the Dallas area. EA's evaluation of the SWPPP preparation has been underway. Their recommendations are expected to be ready in three weeks. Their recommendations
will be provided to all tenants for review and comment. A training meeting will occur between the tenants and AA TI. The formal adoption ofthe recommendations is expected to occur by
the end of June. Three specific areas ofconcern were identified in the ESA Report. The initial area involved aircraft washing. The second area involved floor drains. The final area included
exterior chemicalfwaste storage areas, Aircraft Washing All tenants have been advised that aircraft washing is no longer allowed on the airport property without proper containment. Tenants
with facility drains inside their hangers are allowed to continue to wash aircraft as long as none ofthe wash water enters the storm system. Exterior aircraft washing has been eliminated
except when using a system designed to collect wash water prior to entering the storm system. One tenant has purchased an aircraft washing boom system that complies with this requirement.
AA TI is evaluating the need for an aircraft wash rack on the airport property. This system could be used to wash aircrafts outside. Several tenants are evaluating plans to build wash
rack facilities at their facility. Floor Drains The ESA Report identified three facilities where the floor drains discharged directly to the storm sewer system. The report indicated
that several other tenants did not know iftheir drains connected to the storm or sanitary sewer. CDM recommended that a study be conducted ofany floor drain in question and appropriate
action be taken to eliminate any discharges through these drains to the storm system. AA TI conducted a study ofthe floor drains in the facilities at the Addison Airport. Four facilities
were found to have floor drains connected to the storm system. These include the 600 Series Hangers; 800 Series Hanger, Stem FBO, and Classic Aviation. The floor drains at Classic Aviation
have been plugged with a concrete seal. The floor drains in Stern FBO will be plugged with concrete within the next three weeks. Discharge to these drains have been eliminated but the
plugging ofthe drains cannot occur until a current tenant vacates. The floor drains in the 600 and 800 Series Hangers are being connected to the sanitary sewer system. The estimated
costs ofthese activities are $20,000. Addison Airporr Plon ofAction Page 15 prepared by Addison Airport ofTe:r:as, 1m:., 
Exterior Waste/Chemical Storage Areas The ESA Report identified several areas with exterior waste/chemical storage. Some ofthese areas had evidence of surface staining associated with
them. The discussion and planned actions for the surface staining are contained in Section 2.4. A meeting was held with the tenants identified in the ESA Report to discuss alternatives
to their current storage practices. Most ofthe tenants have installed proper storage for the areas. AAII continues to work with the remaining tenants to ensure that they are upgrading
their storage facilities. 2.2.3 Drainage Swales Large drainage swales/channels are located near the north and south ends of the airport property. Smaller drainage ditches are located
along the runway and through the various airport facilities. Storm water enters the airport property from the surrounding community on all sides. The ESA Report identifies the drainage
swales as potential environmental concerns since contaminated sediment may accumulate in them. The ESA Report recommends the assessment ofthe sediments contained in the drainage swales.
The initial step in assessing the sediments in the drainage swales will include the collection of three composite sediment samples from each ofthe three primary drainage swales. The
composite samples will be collected from near surface sediments in accordance with standard industry practices. Laboratory analyses for total petroleum hydrocarbons (TPH), volatile organic
compounds (VOC), semi volatile organic compounds (SVOC) and total metals will be performed on each of the composite sediment samples. Compounds detected in the sediment samples at levels
above the acceptable levels will be identified as the COe. The remaining 7 assessment of each drainage swale will be designed to address the COe.L 􀁾􀁢􀁦􀀮􀁾. IfCOC are identified in
the surficial sediment sample from any drainage swale, a more complete assessment will be implemented. Up to four hand auger borings will be installed. The hand auger borings will be
installed to depths of6 -8 ft in an attempt to determine the vertical extent of any impact The vertical extent ofthe impact will be determined by collecting soil samples at 2 ft intervals
from each boring. Soil samples collected from the area with a suspected solvent or fuel impact will be field screened for volatile constituents with a Photo Ionization Device (PID).
Soil samples collected from an area with suspected waste oil or heavier petroleum products \vill ,,.' be field screened for volatile organics with a PID and for nonvolatile constituents
with a Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. In addition, composite sediment samples will be collected from two locations up gradient from the original composite sample
locations. A&lison Airport Plan ofAction Page 16 prepared by Addison Airport ofTcxtlS. Inc" 
Two soil samples (highest PID reading and total depth) will be collected from each ofthe hand auger borings installed to determine the vertical extent ofthe impact These samples and
the up gradient composite samples will be submitted to the laboratory for the analysis for the COe. The estimated cost to conduct the assessment ofa drainage swale is $15,000 The total
cost for assessing the three primary drainage swales is estimated to be $45,000. Since the assessments of the drainage swales are Priority 3 items, the cost estimate will be included
in the request for next fiscal year. 2.3 Emergency Spill Response Plan As previously discussed, the plan for addressing the potential environmental concerns identified in the Phase 1
report has been prioritized based on the degree ofpotential impact. The preparation ofthe emergency spill response plan is a Priority 1 activity. The plan is currently being prepared
and is expected to be completed within the next four weeks. The emergency spill response plan will define the reporting requirements and necessary actions for any spill offuel or other
chemicals at the Addison Airport. It will be very specific on the requirements. The location and use ofspill response equipment and materials will be detailed. A mandatory training program
will be required for each tenant ofthe airport as part ofthe fuel permit requirements to ensure that each have fully trained staff. AA TI is considering requesting the Town ofAddison
to implement a penalty system for noncompliance with the emergency spill response plan. The Spill Prevention, Control, and Countermeasures (SPCC) Plan for the fuel farm area will be
incorporated into the emergency spill response plan. The emergency spill response plan will also be incorporated into the best management practices ofthe Storm Water Pollution Prevention
Plan that is being developed. 2.4 Surface Spills and Stained Soil According to the February 1998 Phase 1 Environmental Assessment report prepared by CDM, numerous "significant fuel/chemical
spills" have occurred and areas ofstained soil observed at the Addison Airport. The information concerning the fuel/chemical spills and soil staining was obtained through review ofexisting
data (Section 6), interviews with Town/AATI staff and tenants (Section 2), and the on-site visual survey (Section 4). CDM lists the most significant fuel/chemical spills and soil stains
identified during the site assessment in Section 7.1.2. In many cases, the information provided on the suspect area is marginal and based on someone's rl(fdiSOll AirpOYI Plan ofAcJ.iOtl
Page 17 prepared by Addisoll Airport o/Te.'«l's, Inc. 
recollection of an incident which occurred years before. The VSS provided additional data on the suspect areas, but in many cases this data showed no current visual impacts. A prioritized
plan was developed in order to effectively address the potential impacts of the fuel/chemical spills and stained soil areas identified in the Phase I report. The initial step of the
plan was to conduct a more intensive review of existing information to obtain more information on the suspect areas. The second step was to conduct an inspection oftne areas identified
in the Phase I report to prioritize further actions on this matter. This was completed on April 24 by representatives of AATJ, their environmental consultants, and the Town ofAddison.
The suspect areas identified in the Phase I report were then prioritized into the following categories: Priority 1: Imminent threat to human health or the environment or under direct
supervision of a regulatory agency; Priority 2: Potential threat to the environment; requires further assessment and possible remediation; and Priority 3: No apparent threat to the environment;
requires further assessment to verify. Activities have been implemented and remedies pursued for all Priority I items. Plans have been developed and cost estimated prepared for the Priority
2 items. A request to increase the 􀁾􀀠Addison Airport Upkeep Budget for this fiscal year has been submitted in order to implement _ these plans. Plans and cost estimates are being finalized
for the Priority 3 items. These items will be included in the Upkeep Budget request for next fiscal year. This section provides the information concerning the suspect areas and their
potential impact to the environment It does not include their potential impacts to the storm water permit and Storm Water Pollution Prevention Plan at the airport. Those potential impacts
are contained in the Storm Water Section, The foTiowing paragraphs detail the observations and plans for the areas of concern listed in the Phase I report. 2.4.1 Priority 1 Sites None
ofthe "significant fuelfchemical spills and stained soil" sites identified in the Phase I report present an imminent threat to human health or the environment However, several ofthe
sites are under direct supervision ofa regulatory agency. The sites associated with the fuel farm area are under TNRCC oversight and the sites associated with storm water issues are
under EPA oversight Three Priority I sites are associated with the fuel farm area. Several discussions with AATI staff Addison Airpol'l Pian afAe/ion Page 18 pl'epareeJ by 􀁁􀁤􀀬􀁈􀁾􀁯􀁮􀀠Airport
oj'Te.tas, Inc. 
and tenants reference surface spills of fuels in this area, In addition, observations made during the VSS indicate evidence offuel stains in the area, The operators ofeach of the individual
fuel farms that are referenced in the interviews have been working with the TNRCC on the assessment and remediation ofthe sites. Each ofthese sites were assigned a Leaking Petroleum
Storage Tank (LPST) Number by the TNRCC, Details of the activities performed on these sites is contained in the Fuel Storage and Dispensing Operations section, Several of the sites with
evidence of surface stains or a history of spillage are considered Priority 1 due to their potential impact on the storm water discharge quality, The sites are not listed as Priority
1 in this section but are discussed ingreater detail in the Storm Water section, 2.4.2 Priority 2 Sites The Priority 2 sites include those sites with more than a nominal chance ofhaving impacted the subsurface, The activities
planned for these sites are primarily designed to assess any impact. Appropriate plans and cost estimates for remediation will be prepared based on the assessment results, Building No.2
COOP T -Hanger -Building B Potential Environmental Concern I) Stained soil was observed at east end ofbuilding, 4/24/98 Observations This area is the same as the area located west. of
Building No, 3, See below for observations and planned action, AATlAction See Building 3 Building No.3 COOP T -Hanger -Building C Potential Environmental Concern I) Stained soil was
observed at east and west ends ofbuilding. 2) AST located at east end and petroleum staining was observed at the base ofthis tank 4/24/98 Observations The AST has been removed from the
site, Three small areas (one was -2' in diameter and two were -1' in diameter) ofsoil staining was observed in the area ofthe former waste oil Addison Airport Plan ifAction Page 19 prepared
by Addison Airport a/Texas, Inc. 
tank (east end ofbuilding). The soil staining did not extend beyond 4" deep, Guardtop had been placed on the rocks west of the building (between Building Nos 2 and 3), The area covered
was -2' wide by 8' long. The Guardtop has solidified at the surface, AATIAction Area east of building; remove approximately 6" of top soil from the areas of the soil staining and replace
with clean fill. Install two hand auger borings in the location of the surface staining, The borings will be installed to depths of 6 -8 ft in an attempt to determine the vertical extent
ofany soil impact The vertical extent ofthe impact will be determined by collecting soil samples at 2 ft intervals from each boring, Soil samples collected from the area will be field
screened for volatile constituents with a Photo Ionization Device (PlD) and Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. Up to two soil samples (highest PlD reading and total
depth) will be collected from each ofthe hand auger borings installed to determine the vertical vertical extent ofthe impact The samples will be submitted for laboratory analysis for
volatiles, semi-volatiles, P AH, total petroleum hydrocarbons (TPH) and total metals, Area between Building Nos 2 and 3, no action. Estimated Cost $2,400 Building No. 25 Classic Aviation
Flight School, Hanger, Maintenance and Automobile Shop Potential Environmental Concern 2) Stained soil vvas observed in the drainage ditch adjacent to the north end of the building ,A
floor drain and sink in the automotive shop discharge directly into this drainage ditch. 4/14/98 Observations There are three areas ofimpact located along the north side ofthe automotive
shop. One associated with each the sink, floor drain and either additional drain or discharge out ofthe front door. The sink discharge area covers approximately an area 4' by 10'. The
floor drain area was about 6' in diameter. The third area was about the same as the sink area, Two soil samples were collected and screened with an OVM. Both samples had detectable levels
of volatile organic vapors in excess of 1,000 parts per million (ppm). AA Tl Actioll 􀁾􀀠Inform current lessee of the potential environmental concern and subsequent observations. 􀁾__s_u_gg_o_e_st_t_
h_a_tt_h_e_le_s_se_e_co_n_d_u_c_t_an_en_v_i_ro_n_m_e_n_t_al_a_s_s_es_s_m_e_n_t_o_f_th_e_a_r_ea_,____-..,.___ Addison Airport Pfan ofAclian Page 20 prepared by Addt"son .4irpor( QfTems,
Inc, 
Building No. 29 Walter Fuller Aircraft Sales Hanger and Maintenance Shop Potential Ellvironmental Concer/! I) A waste oil AST was located outside on the north end ofthe building. Stains
were observed in the soils located beneath the tank and at a separate location along the north side ofthe building. 5) Stained soil was observed in the grassy area south ofthis building
and petroleum staining was observed in a nearby drainage ditch. 4124/98 Observations The waste oil AST had been removed from its location. It was still present at the site but not in
use. A concrete pad with curbs has been constructed in the area where the AST was located. Construction ofthis pad has removed any stains ofthe soil. An area ofimpacted grass approximately
6' by 50' was observed to the south ofthis building. The distressed vegetation was not continuous through the area. There was not any connection between the location ofthe impacted areas
and potential sources. It appeared that someone had dumped the materials at several locations. One location was stained white with paint. The areas smelled like solvents. Two storm sewers
meet at a location SW ofthis building in the grass between the taxiway and ramp. Heavy oil staining was observed between these pipes. The storm water flows from the south to the north.
AATIAction Inform current lessee ofthe potential environmental concern and subsequent observations. Suggest that the lessee conduct an environmental assessment ofthe area. Building No.
30 Jet 10 Hanger Potential Environmelltal COllcer/! I) Soil staining was observed between this hanger and the adjacent All American Aviation Hanger. 4124/98 ObservatiollS The observations
ofthe area between this building and Building No. 31 are listed below. It appears that the soil staining is a result ofoperations from Building 31. AATIActiOlI See Below ,􀁾􀀠. Addison
Airport Platt ofAelion Page 21 prepare,{ by Addison Airport o/Texas./nc. 
Building No. 31 All American Aviation Hanger and Maintenance Hanger Pote1!tial Eflviroflt1U!1!tal COflceT1! I) Soil staining was observed between this hanger and the adjacent Jet 10
Hanger. 4124/98 Observatiofls Two areas of soil staining were observed between the building and Building No. 30. The first area covered approximately 4' by 10'. It smelled ofsolvents
and appeared to have originated from the adjacent chemical storage area. ' The second area was located in the NW corner ofthis area adjacent to Building No. 30. This area appeared to
be impacted by waste oil. The impacted area was less than 5' in diameter. AA TI Acti01! The initial step is to determine the chemicals of concern (COC). Collect a composite surficial
soil sample from each ofnoted soil staining. Submit the soil samples to the laboratory for analyses oftota! petroleum hydrocarbons (TPH), volatile organic compounds (VOC), semi volatile
organic compounds (SVOC) and total metals. Compounds detected in the soil sample at levels above the acceptable levels will be identified as the COCo Each of the areas ofnoted soil staining
may have different COe. The remaining assessment at this facility will be designed to address the COCo Install one hand auger boring in each of the areas ofsoil staining. The hand auger
borings will be installed to depths of6 -8 ft in an attempt to determine the vertical extent ofany soil impact. The vertical extent ofthe impact will be determined by collecting soil
samples at 2 ft intervals from each boring. Soil samples collected from the area with a suspected solvent or fuel impact will be field screened for volatile constituents with a Photo
Ionization Device (PI D). Soil samples collected from an area with suspected waste oil or heavier petroleum products \\111 be field screened for volatile organics with a PID and for
nonvolatile constituents with a Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. After determining the vertical extent ofimpact, up to 15 additional hand auger borings will be installed
to determine the horizontal extent of impact at the depth shown during field screening. Two soil samples (highest PID reading and total depth) will be collected from each ofthe hand
auger borings installed to determine the vertical extent ofthe impact. The samples wiIl be submitted to the laboratory for the Two soil samples (highest PID reading and total depth)
will be collected from three hand auger borings located on the perimeter ofthe impacted area and will be submitted for COC analyses. If groundwater or competent limestone is encountered
before determining the vertical extent ofimpact in the initial three hand auger borings, hand auger boring installation will continue as planned in an effort to determine the horizontal
extent ofthe impact area. 􀁾􀀮􀀠' Addison Airporf Pkm ojAcJicm Page 22 prepartfll byAddison Airport ofTtXOs, Inc, 
After determining the horizontal impact area, a truck mounted drill rig will be utilized to install four 2 in. diameter temporary monitor wells for the collection ofgroundwater samples.
Soil from each monitor well will be sampled continuously, and samples collected from each 2 ft interval for field screening and possible laboratory analyses. Up to three soil samples
(highest PID reading, groundwater interface and total depth) from each well will be submitted for cae analyses. After installation ofthe monitor wells, the top ofcasing elevations will
be surveyed. Depth to water measurements will be collected in all wells to determine groundwater gradient. All wells will then be developed, purged ofall groundwater, and sampled after
groundwater recharges. Groundwater samples will be submitted for cae analyses. Estimated Costs $42,000 2.4.3 Priority 3 Sites The Priority 3 sites have very low possibilities of impacting
the enviromnent. However, in order to better understand the possibility additional assessment is needed. The activities planned for these sites are primarily designed to provide an initial
assessment ofany impact. Appropriate plans and cost estimates for further assessment or remediation will be prepared based on the assessment results. Building No.4 300 Series T-Hangers
Potential Environmental Concern 1) AST located at south end ofbuilding and soil staining observed under tank. 2) Large fuel spill was occurred in 320. 3) Small soil and rock staining
observed in Hangers 17 and outside Hanger 10. 4124/98 Observations The floors ofthe hangers are concrete and asphalt. All staining was on the impermeable surface. The AST has been removed.
No soil staining was observed in the vicinity ofthe former AST. AATIAction Install 1 scil boring at the location ofthe former waste oil AST. Analyze soil sample for volatiles, semi-volatiles,
metals, P AH, and total petroleum hydrocarbons. Estimated Cost $1,600 Addison Airporl Pian ofAcrion Page 23 prepared by Addison Airport ofTe.'((Js, inc, 
Building No.5 400 Series T-Hangers Potelltial Envirol/mel/tal COl/cern 1) Minor soil staining was observed in Hangers 5, 8, and 22. 4/24/98 Observations The floors ofthe hangers are
concrete and asphalt. All staining was on the impermeable surface. AATI Action None Building No.6 500 Series T-Hangers Potential Environmental Concem 1) Minor soil staining was observed
in Hangers 5, 6, 9, and 11. 4/24/98 Observations The floors of the hangers are concrete and asphalt. All staining was on the impermeable surface. AATlAction None Building No.7 Cragin
Aviation Hanger and Maintenance Shop Potential Envirol/mental ConcertI 5) Soil staining was observed along the northern exterior wall and in adjacent drainage ditches. 4/24/98 Observations
The "soil staining" observed along the northern exterior wall of the building and shown in Photo # 34 is sandblasting sand. A small parts sandblaster is vented to the exterior at this
location. A small amount of residual sandblasting sand is released. The residual sandblasting sand sand does not pose a threat to human health or the environment. According to the ESA
Report, the staining of the drainage ditch behind this facility did not originate from this facility. No soil staining was observed in the drainage ditch behind this facility. The distressed
vegetation shown in Photo #33 is most likely from standing water and not petroleum impacts. The potential environmental concern from the stained soil in the drainage ditch, as identified
in the ESA Report, is covered under the S!':ytech Facility. 􀁁􀁤􀁤􀁩􀀮􀁾􀁯􀁮􀀠Airport Plan ofAction Page 24 prepared by Addison Airport 􀁱􀁦􀁔􀁥􀀺􀁾􀁡􀁳􀀬􀀠Inc. 
AA TIActioll None Building No.8 Sky tech Aviation Hanger and Maintenance Shop Potelltial Ellvironmelltal COlICem 4) Soil staining was observed at the east end ofbuilding between Skytech
and AV Group hangers. Stained asphalt was also observed beneath the exterior waste oil storage tank located at the NE comer of the building. According to the ESA Report, the most likely
source of the stained soil in the drainage ditch behind the Cragin Facility is the former floor drain discharge from this facility. 4124/98 Observations The only staining observed at
the east end of the building was associated with the exterior waste oil storage tank. The staining is limited to the asphalt area as seen in Photo # 61. No soil staining was observed
in the drainage ditch behind the Cragin Facility. The distressed vegetation shown in Photo #33 is most likely from standing water and not petroleum impacts. AATIAction The ESA Report
identifies the most likely source ofthis stained soil behind the Cragin Facility as the discharge from the Millennium and Skytech facilities prior to their connection to the sanitary
sewer system. These facilities are owned by the Town of Addison. Since the potential source ofthis concern cannot be attributed to a lessee, the following activities will be performed.
Install 2 soil borings in the drainage ditch behind this facility. The borings will be installed to depths of6 -8 ft in an attempt to determine the vertical extent of any soil impact.
The vertical extent of the impact will be determined by collecting soil samples at 2 ft intervals from each boring. Soil samples collected from the area will be field screened for volatile
constituents with a Photo Ionization Device (PID) and Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. Up to two soil samples (highest PID reading and total depth) will be collected
from each ofthe hand auger borings installed to determine the vertical extent ofthe impact. The samples will be submitted for laboratory analysis for volatiles, semj-volatiles, PAH,
total petroleum hydrocarbons (TPH) and total metals. Estimated Cost $3,000 Addison Airport Plan 0/Action Page 25 prepared byAddison Airparl a/Texas, Inc. 
Building No.9 Aviation Management Hanger and Maintenance Shop Potential Envirollmental COllcem 4) Former waste oil AST was located behind their fuel trucks and staining was previously
observed by tenant below the tank. 7) Stained soil and rock was observed on west end of building. 8) Four fuel trucks are parked on apron. Numerous small asphalt stains from previous
fuel spills were observed. 9) A 55-gallon sump fuel drum was located behind fuel truck parking area. Stained asphalt from previous spills were observed at the base ofdrum. 10) Stained
soil and asphalt were observed near the end ofthe concrete fence located in front of Av Group facility. 4124/98 ObservatioflS A waste oil AST was not found at this facility. The sump
fuel drum had been removed. Small areas ofpetroleum staining were observed on the asphalt at the locations of the former AST and drum. The fuel trucks continue to be parked on the apron
ofthis facility. Small areas ofstaining were observed on the asphalt near the fuel truck parking. Stained soil and rock was not found on the west side ofthe building. The only staining
observed on the west side ofthe building was that associated \vith the chemical and waste storage practices at Building 8. Stained asphalt was observed at the north end ofthe concrete
fence located to the east ofthis facility (Photo # 46). There was no evidence that this petroleum staining extended beyond the asphalt covered area. AATIAction Install 1 soil boring
at the location of the former waste oil AST. Install I soil boring at the north end of the concrete fence located to the east ofthe facility. Install 2 soil borings in the area where
the fuel trucks are parked. The borings will be installed to depths of6 -8 ft in an attempt to determine the vertical extent ofany soil impact. The vertical extent ofthe impact will
be determined by collecting soil samples at 2 ft intervals from each boring. Soil samples collected from the area will be field screened for volatile constituents with a Photo Ionization
Device (PID) and Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. Up to two soil samples (highest PID reading and total depth) will be collected from each ofthe hand auger borings
installed to determine the vertical extent ofthe impact. The samples \vill be submitted for laboratory analysis for volatiles, semi-volatiles, PAH, total petroleum hydrocarbons (TPH)
and total metals. Estimated Cost $7,000 ,..Jddison .-!irporf Plan alAelion Page 26 prepared by Addison Airport ofTf!Xf1S, Inc, 
Building No. 10100 Series T-Hangers Potential Environmental Concerti I) Minor soil/asphalt staining was observed in Hangers 3, 10, 15, and 17. 4124/98 Observations The floors ofthe hangers
are concrete and asphalt. All staining was on the impenneable surface. AATIAction None Building No. 11 200 Series T-Hangers Potential Environmental Concerti 1) Minor soil/asphalt staining
was observed in Hangers 5, 9, II, and 15. 2) A large soil stain resulting from Guardtop spillage was observed in Hangers 19 and 20. 4124198 Observations The floors ofthe hangers are
concrete and asphalt. All staining was on the impenneable surface. The ground inside Hanger 19 and 20 is covered with asphalt and concrete. The spill reported by CDM appears to involve
diesel fuel instead ofGuardtop. AATI Action Recommendations have been made to the tenant ofHangers 19 and 20 to check the integrity of the impenneable surface and repair it iffound to
be deficient Collect one soil sample from the native material beneath Hangers 19 and 20. Analyze the soil sample for BTEX, PAH, and total petroleum hydrocarbons. Estimated Cost $1,000
Building No. 14 Omniflight Helicopters Hanger and Maintenance Shop Potential Environmental Concerti I) An exterior waste/chemical storage area were observed. Stained soils and asphalt
were also observed in the waste storage area. Addl.son Airport Plan ofAcfimJ Page 27 prepared by Addisoll Airporl a/Texas, Inc, 
4124198 Observations The area beneath the waste/chemical storage area has been paved with asphalt. This area needs to be upgraded in order to meet the SWPPP requirements. AATIAction
Inform current lessee ofthe potential environmental concern and subsequent observations. Suggest that the lessee conduct an environmental assessment of the area. Building No. 15 Open
Air Hangers Potential Environmental Concern 1) A waste oil AST was located north ofthis building. Petroleum staining was observed on the asphalt at the base ofthis tanle 4/24/98 Observations
The waste oil AST has been removed. Minor staining was observed on the asphalt at the location of the former AST. AATIAction Install 1 soil boring at the location of the former waste
oil AST. The boring will be installed to depths of6 -8 ft in an attempt to determine the vertical extent ofany soil impact. The vertical extent ofthe impact will be determined by collecting
soil samples at 2 ft intervals from each boring. Soil samples collected from the area will be be field screened for volatile constituents with a Photo Ionization Device (PID) and Petroflag
Total Petroleum Hydrocarbon (TPH) analyzer. Up to two soil samples (highest PID reading and total depth) will be collected from each ofthe hand auger borings installed to determine the
vertical extent ofthe impact. The samples will be submitted for laboratory analysis for vola!iles, semi-volatiles, P AH, total petroleum hydrocarbons (TPH) and total metals. Estimated
Cost $1,500 Building No. 19 Henley's Aircraft Services Hanger and Maintenance Shop Potential Environmental Concern I) Stained asphalt from previous fuel spills was observed various locations
on their ramp. 4124198 Observations All stains are contained on the paved ramp. AATIAction None Addison Airport Plan ofAction Page 28 prepared by Addlsoll Airport ojTe,"(.(ls, Inc. 
Building No. 24 Associated Hanger, Inc. Potential Environmental Concern I) A steel pipe is located in the ground on the north side of the building. This pipe could possible be a vent
pipe or fill port for an UST. 2) Stained soil was distressed vegetation were observed in the grassy area along the north end of this building and between the Omniflight apron and Centerline
tie down areas. 4124/98 Observations The steel pipe cannot be located. According to the tenant, he found the steel pipe when it was first identified by CDM but has not been able to find
it since. He said the pipe appeared to be part ofa recreation area and not associated with an UST. The "soil staining and distressed vegetation" shown in Photo # 38 is not present. The
distressed vegetation shown in the photo appears to be due to truck traffic, not petroleum impacts. One small area ofrecent soil staining was observed. An aircraft was parked on the
apron with its nose over the grassy area. Motor oil was observed leaking from the engine. The impacted area was approximately 2' in diameter and less than 6" deep. Three small areas
of what appeared to be residual roofing tar or topcoat were observed on the north side of this building. AATIAction Inform current lessee ofthe potential environmental concern and subsequent
observations. Suggest that the lessee conduct an environmental assessment of the area. Building No. 28 Concourse Plaza Office Building and Hanger Potelltlal Environmental Concern 1)
A plane was observed leaking fuel from a wing fuel tank. 4124/98 Observations The asphalt ramp area had several areas ofsmall fuel stains. AA TlAction Inform current lessee of the potential
environmental concern and subsequent observations. Suggest that the lessee conduct an environmental assessment of the area. A,ldison Airpol'l Plan ofAclion Page 29 prepared by Addison
Airport o/Te.tas, /nco 
Building No. 32 Series 600 Hangers PotenJial E'lvironmenJal Concern 2) Stained soil was observed at the NW comer of the building and in the open area between the two hanger bUildings.
4/24/98 Observations No soil stains were observed at this facility. AATIAction None Building No. 36 Open Air Hangers Potential Environmental Concern I) A waste oil AST is located at
the north end ofthe building. Stains were observed on the asphalt beneath and adjacent to this tank. 4/24/98 Observations The waste oil AST has been removed. Minor staining was observed
on the asphalt at the location ofthe former AST. AATJAction Install I soil boring at the location of the former waste oil AST. The boring will be installed to depths of6 -8 ft in an
attempt to determine the vertical extent of any soil impact The vertical extent ofthe impact will be determined by collecting soil samples at 2 ft intervals from each boring. Soil samples
collected from the area will be field screened for volatile constituents with a Photo Ionization Device (PlD) and Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. Up to two soil
samples (highest PlD reading and total depth) will be collected from each of the hand auger borings installed to determine the vertical extent ofthe impact. The samples will be submitted
for laboratory analysis for volatiles, semi-volatiles, P AH, total petroleum hydrocarbons (TPH) and total metals. Estimated Cost $1,500 Building No. 47 Warfield Private Hanger Potential
Environmental Concern 1) Stained soil was observed in the drainage ditch adjacent to the north end ofthis building. Addison Airport PlcJn ofA.ction Page 30 prepared by Addison Airport
a/Texas. Inc. 
4/24198 Observations No staining was observed. The impacted area in Photo # 39 appear to be related to standing water, not petroleum spi Ilage. AATIAction None Building No. 48 Mercury
Air FBO Terminal, Hanger and Maintenance Shop Potential Environmental Concern 2) Minor soil staining was observed in the grassy area behind the fuel truck parking area. 4124/980bservatio1lS
Several (4-5) small areas offuel staining were observed behind the fuel truck parking area at this fucility. The areas were approximately 2' in diameter and less than 6" deep. In addition,
waste fuel drums were observed in this area. AATlAction Infonn current lessee ofthe potential environmental concern and subsequent observations. Suggest that the lessee conduct an environmental
assessment ofthe area. Building No. 51 E.U.A. Air Support Hanger and Maintenance Hanger Potential Environmental Concern 2) Stained rock and soil were observed outside along the south
end ofthe building. 4/24/98 Observations An area approximately 6' in diameter was observed to be stained in the rocks next to the south wall ofthis building. The impact did not exceed
2" in depth. AATIAction None Building No. 58 Addison Aviation Services Hanger and Maintenance Shop Potential Environmental Concern 4) The soils in one area oftheir apron appears stained.
A concrete pad was previously located in this area and was used to park their fuel truck. The spill incident records indicate that several fuel spills have occurred on this ramp. Addison
Airport Plan ofAction Page 31 prepared byAddisoll Airport ofTe:ws, Inc. 
4/14/98 Observations All stains were contained on the asphalt. Construction is currently underway at the location of the fonner fuel truck parking area. The surface soils have been moved.
It is not possible to locate those soils that were previously present or stained. The site will be covered with concrete pavement. AATlAction None Building No. 59 Domar Leasing Private
Hanger Potential Environmental Concern 2) Fuel staining was observed on their ramp possibly from the Addison Aviation Services fuel truck. 4114/98 Observations All stains were contained
on the asphalt. AATlAction None Building No. 66 Million Air Hanger and Maintenance Shop Potential Environmental Concern 2) A soil stain was observed in the grassy area south ofthis hanger.
4114/98 Observations A very minor surface stain was noted at this location. The impacted area shown in Photo # 49 appears to be due to standing water rather than petroleum spillage.
AATl Action Infonn current lessee of the potential environmental concern and subsequent observations. Suggest that the lessee perfonn an environmental assessment ofthe area. Building
No. 67 Million Air FBO Terminal, Hanger, and Maintenance Shop Potential Environmental. Concern 2) A fuel spill from a fuel truck has previously occurred in the drainage ditch adjacent
to the Mill ionaire facility. Addison Airporl PUm o.fAClitm Page 32 prepared by Addison Airport a/Texas. Inc. 
4) Fuel trucks park adjacent to a drainage ditch on the Millionaire facility. 4124198 Observations No visual evidence ofthe previous fuel spill to the drainage ditch was observed. The
fuel truck park adjacent to this drainage ditch. AATIAction Inform current lessee of the potential environmental concern and subsequent observations. Suggest that the lessee conduct
an environmental assessment of the drainage ditch. Ramp Between Interjet, E.U.A. and Redman Investments Potential Ellvirollnumtal Concem According to an interview, a fuel truck spilled
500 gallons ofJet A at this location. It is unclear how much ofthe fuel was recovered or drained into the grassy areas. 4124198 ObservatiollS No visual evidence ofthe previous fuel spill
to this area was observed. AATI Action Inform current lessee ofthe potential environmental concern and subsequent observations. Suggest that the lessee conduct an environmental assessment
ofthe area. Skyworks Aviation Potential EllvirOllmellul1 COllcem An USEPA document indicated that paint related materials were dumped into the dumpster and on the land surface at this
facility. 4124198 ObservatiollS No visual evidence of this area was observed. AATIAction Install 4 soil borings in the area. The borings will be installed to depths of6 -8 ft in an attempt
to determine the vertical extent ofany soil impact. The vertical extent ofthe impact will be determined by collecting soil samples at 2 ft intervals from each boring. Soil sam pies collected
from the area will be field screened for volatile constituents with a Photo Ionization Device (PlO) and Petroflag Total Petroleum Hydrocarbon (TPH) analyzer. Up to two soil samples (highest
PlO reading and total depth) will be collected from each ofthe hand auger borings installed to determine the vertical extent ofthe impact. The samples \vill be submitted for laboratory
analysis for volatiles, PAH, and total petroleum hydrocarbons Addison Airport Plan o/Action Page 33 prepared byAddison Airport a/Texas,lnc. 
(TPH). Estimated Cost $7,500 2.5 Suspected Fill Areas According to the February 1998 Phase I Environmental Site Assessment perfonned by CDM, suspectedfill areas are located at the north and south ends of the main runway and along the western property boundary in several locations. Another suspected fill area was also identified beneath
the current Million Air facility. The report further explains that it is believed that some ofthe fill areas may contain construction debris. The complete contents ofthe fill in each
area are unknown. In the Phase I report, CDM recommends that each fill area be investigated to detennine the makeup of the fill material. If fill materials are found, the investigation
should be expanded to detennine the presence ofany soil and !,'l'oundwater contamination in each area. As previously discussed, the plan for addressing the potential environmental concerns
identified in the Phase 1 report has been prioritized based on the degree of potential impact. The suspected fill areas identified in the Phase 1 report appear not to present a threat
to the environment but assessment is needed in order to verity this. Therefore, the assessment activities proposed for the suspected fill areas are Priority 3 activities. The plan and
cost estimate have been finalized for the Priority 3 items, These items will be included in the Upkeep Budget request for next fiscal year. According to airport personnel, a large portion
of the airport property contains fill material. Much of the fill was taken from off-site fill areas. Construction debris has also been used periodically since the 1970's. The Town of
Addison was aware ofand endorsed the use of the construction debris as fill material. In fact, much ofthe construetion debris was generated at Town of Addison construction projects.
Since the suspected fill areas do not present an imminent threat to human health or the environment, the assessment ofthe areas has been assigned a lower priority. The lower priority
items will be included in the Upkeep Budget ofthe airport for the upcoming fiscal year. AA TI proposes to use a combination of magnetometer survey and subsurface sampling and analyses
to assess the suspected fill areas, The suspected fill areas have been divided into three areas, north of the runway, south of the runway, and west ofthe runway. The same scope of work
will be used for each ofthese areas, The initial step of the assessment is the use of a magnetometer survey to assess whether subsurface anomalies exist in the areas which could be indicative
of buried containers (storage Am/iSDn Airport Plan ofAction Page 34 prcptlred by Addison Airport ojTt!;oos, Inc. 
tanks, drums, etc.). Any metal object such as a storage tank or drum cause magnetic field anomalies that can be detected during a magnetometer geophysical survey. The area to be assessed
must be divided into a predefined grid. The magnetometer survey is conducted using a dual sensor proton precession magnetometer. The magnetic field readings are plotted against the grid
pattern and contoured to provide a graphical illustration of potential tanks, drums, etc. Once the magnetometer survey is completed, soil borings are advanced in the areas of suspected
concerns. Up to 20 soil borings will be advanced in the areas of potential concern. The borings will be advanced using an auger rig through the fill material into native soils. Representative
samples of the fill materials will be logged and recorded. Soil/fill samples will be collected for laboratory analyses for the compounds listed below. Up to five of the soil borings
will be converted into groundwater monitor wells. Groundwater samples will be collected and analyzed for the compounds listed below. The monitor wells will be surveyed and groundwater
elevations will be recorded. During the initial assessment, soil and groundwater samples will be analyzed for metals, volatiles, semi-volatiles, pesticides, herbicides, cyanide and phenols.
Subsequent sampling should be limited to the areas where contaminants are encountered and only to the compounds detected. The estimated cost to perform the assessment at a suspected
fill area is $65,000. The total cost to assess the three suspected fill areas is $ $195,000. 2.6 Septic Tanks According to the February 1998 Phase I Environmental Site Assessment perfonned
by CDM, four facilities indicated that they used septic tanks and associated leach fields prior to the installation ofthe sanitary sewer. It is believed that the sanitary sewer was made
available at the airport in the 1960's. CDM further expands this by saying that all facilities that were present prior to the availability of the sanitary sewer must have been connected
to septic tanks. Since waste products from maintenance activities could have been disposed ofin the septic tank systems for many years, the fonner septic tanks and associated leach fields
present environmental concerns. CDM recommends that a subsurface sampling and testing program be completed to determine the presence ofany subsurface contamination in the area ofthe
former septic tanks. The Phase 1 report identified the following buildings as likely having been connected to septic tank systems: 1. Air Traffic Control Tower 2. Cragin Hanger and Maintenance
Shop Addi,wn Airport Plml 0/Action Page 35 prepan>tl hy Addiwn Ai/pm·1 ofTe.:cas, Inc.. 
3, The Six Hanger and Maintenance Shop 4, 600 Series Hangers 5, Current Omniflight Facility across from Ari Ben Aviator facility 6. Ad Ben Aviator Facility (Old South Terminal) 7. Centerline
Aviation Hanger 8, Classic Aviation Hanger and Maintenance Shop 9. Jet t and 2 10. Mercury Air Hanger 2 (Across from their main FBO terminal) 11, The Av Group and Skytech Hangers (Former
Collins Hangers) 2.6.1 Suspected Septic Tanks 011 Ground Lease Facilities Several ofthe suspected septic tanks are located on ground lease facilities, Therefore the lessee will be requested
to conduct an assessment to determine the location and condition ofthe septic tank and leach field, Those facilities include the following: Air Traffic Control Tower Cragin Hanger and
Maintenance Shop The Six Hanger and Maintenance Shop Current Omniflight Facility across from Ari Ben Aviator facility Centerline Aviation Hanger Classic Aviation Hanger and Maintenance
Shop Mercury Air Hanger 2 (Across from their main FBO terminal) AATIAction Request that the lessee conduct an assessment to determine the location and condition ofthe septic tank and
leach field, 2.6.1 Suspected Septic Tanks on Non-Ground Lease Facilities The suspected septic tanks located on non-ground lease facilities include: 600 Series Hangers Ari Ben Aviator
Facility Jet I and 2 The Av Group and Skytech Hangers As previously discussed, the plan for addressing the potential environmental concerns identified in the Phase 1 report has been
prioritized based on the degree ofpotential impact. The suspected septic tanks identified in the Phase I report appear not to present a threat to the environment but Addison Ah'jroN
Plan ofAction Page 36 prepared by Addison Airport a/Texas. 1M." 
assessment is needed in order to verify this. Any septic tanks at the airport have been in place since the 1960s and have not been in use for a number of years. Therefore, the assessment
activities proposed for the suspected septic tanks are Priority 3 activities. The plan and cost estimate have been finalized for the Priority 3 items. These items will be included in
the Upkeep Budget request for next fiscal year. Even though the assessment of suspected septic tanks is a Priority 3 item, the initial steps have already been performed. The initial
step in assessing the potential impacts from former septic tank systems is to identify their location. A review of the available construction documents for the referenced facilities
were performed. This review did not reveal the locations of any of the suspected former septic tanks and leach fields. The next step was to perform a field inspection, which was conducted
by AATI and their environmental consultants on April 24, 1998. The objectives of the field inspection were to identify any surficial evidence of the potential locations of suspected
septic tanks, document the physical surface conditions, and verify that each ofthe facilities listed are not currently using septic tank systems. The location of former septic tanks
could not be identified at any location from the field inspection. The general direction from the facilities that a former septic tank system would have been located was estimated based
on current sanitary sewer connections and surface topography. Generally, the ground surfaces in these areas are paved with concrete or asphalt covering. This further restricts the ability
to locate any suspected septic tanks. The remaining portions of this assessment are more timely and costly. Since the former septic tank systems have been present for more than 30 years
and have not been in use for a similar length of time, they do not appear to pose an imminent threat to human health or the environment. A lower priority has been assigned to this activity.
The lower lower priority items will be included in the Upkeep Budget of the airport for the upcoming fiscal year. AATl proposes to use a combination of magnetometer survey and resistivity
survey to locate the former septic tanks. Following the location of a septic tank, it will be uncovered to determine the location of its associated leach field. A subsurface investigation
will be conducted to determine the impacts ofthe septic tank and leach field to the environment. The same scope of work will be utilized for each ofthe J I facilities listed above. The
initial step of the assessment is the use ofa magnetometer survey to assess whether subsurface anomalies exist in the area which could be indicative ofa buried reinforced concrete structure
such as a septic tank. The reinforcing steel can cause magnetic field anomalies that can be detected during a magnetometer geophysical survey. The area to be assessed must be divided
into a predefined grid. The magnetometer survey is conducted using a dual sensor proton precession precession magnetometer. The magnetic field readings are plotted against the grid pattern
and contoured to provide a graphical illustration of location of a septic tank Addisvn AirpOH Pion ofAcrfOll Page 37 prepared by Adolison Airport o!Te.\'{I$, InC'.. 
In the areas where the magnetometer survey is inconclusive, a resistivity survey will be conducted. The resistivity survey uses the grounds natural resistivity to identifY the locations
of any voids such as the inside of a septic tank. A grid wiII be set and the resistivity survey will be conducted. Results from the resistivity survey will be graphed to show the locations
ofany suspected septic tanks. Once a septic tank is located by the magnetometer surveyor combination ofthe surveys, the top of the septic tank will be excavated. Examination ofthe septic
tank will assist in locating the associated leach field. Once the septic tank and associated leach field have been located, a subsurface investigation will be conducted. Three soil borings
will be advanced in the area, one at the septic tank and two in the leach field. The borings will be advanced using an auger rig and representative samples of the soil will be logged
and recorded. Soil samples will be collected for laboratory analyses for metals, volatiles, semi-volatiles, pesticides, herbicides, cyanide and phenols. One soil boring will be converted
into a temporary groundwater monitor well. A groundwater sample will be collected and analyzed for metals, volatiles, semi-volatiles, pesticides, herbicides, cyanide and phenols. If
the laboratory analyses do not encounter any compounds that present a concern, the septic tank will be filled with sand and left in place. Ifsubsurface contamination is encountered,
a site assessment will be conducted in accordance with the TNRCC Hazardous and Industrial Waste Section requirements. The estimated cost to perform the assessment at a suspected septic
tank area is $15,000. The total cost to assess the four facilities is $60,000. These costs do not include the cost ofany additional assessment or remediation beyond the initial assessment.
2.7 Other Areas The ESA Report identified several potential environmental concerns that could not be categorized in the previous areas ofconcern. This section identifies those potential
environmental concerns and provides the plan of action to address each. 2.7.1 Hydraulic Lifts According to the ESA Report, two facilities at the Addison Airport utilize underground hydraulic
lifts which have the potential to impact subsurface soil and groundwater in the event of a release ofpetroleum products. The facilities are the Town ofAddison Service Center and the
Six Hanger. Properly maintained hydraulic lifts pose a very minimal risk to the environment. Addison Airport Plan ofAction Page 38 prl!partul hy Addison Airpan a/Texas,lnc., 
AATIActions AA TI will request maintenance and repair records from the operators ofthe hydraulic lifts. The records will be reviewed for any indication ofleakage. Estinwted Costs $100
2.7.2 Petroleum Pipeline According to the ESA Report, an underground petroleum pipeline is located along the railroad tracks adjacent to the southern airport boundary. The report indicated
that this petroleum pipeline could pose an environmental concern to the airport property due to its close proximity. AATIAction None Addison Airport Plan ofAction Page 39 prepared byAddison
Airport ofTexi1$, Inc" 
3. Costs Summarized The following table summarizes the estimated costs associated with the activities conducted and planned to be conducted to address the potential environmental concerns
identified in the ESA Report. These costs cover the activities needed in order to assess whether the potential environmental concerns are environmental problems. The estimated costs
are only those that have or will be incurred in connection with the upkeep ofthe airport. They do not include any costs incurred by the tenants. These estimated costs have been prepared
using the data that is available at this time. Certain Priority I items need to be completed in order to obtain a better understanding of the potential environmental concern. As additional
data becomes available, these costs may need to be revised. These costs do not cover any remediation ofany site. Should the assessment acti vities indicate that remediation is needed,
a work plan and cost estimate will be prepared. Area of Concern Priority I Priority 2 Priority 3 I Activities Activities Activities IFuel St?rage and Dispensing Operahons i , $49,500
. Storm Water Management $50,000 $45,000 r--Emergency Spill Response Plan $12,500 Surface Spills and Stained Soil $6,000 $44,400 523,100 Suspected Fill Material $500 $195,000 Suspected
Septic Tanks $4,000 $60,000 Other Areas $600 Contingency (15%) $18,500 $6,700 $48,500 Total $141,600 $51,100 $371,600 Addison Airport Pkm ofAction Page 40 prepan:d byAddisOt1 Airport
ojTe:tas. Inc," 
CDM Camp Dresser & McKee Inc. consulb"ng engineering constrocfion operations One Glen Lakes 8140WainutHili 􀁾􀁡􀁮􀁥􀀬􀀠Suite 1000 Dallas, Texas 75231 Tel: 214 346-2800 Fax: 214 987-2017
June 12, 1998 Mr. Jim Pierce, P.E. Town of Addison P.O. Box 144 Addison, Texas 75001-0144 Re: Review of Addison Airport Action Plan Addison Airport Addison, Texas Dear Mr. Pierce: Camp
Dresser & McKee Inc. (CDM) has completed our review of the Addison Airport Action Plan that was recently developed by Addison Airport of Texas, Inc. (AATI) to address the environmental
concerns identified in the Phase I Environmental Site Assessment (ESA) that was previously completed for the subject property by CDM. Based on our review of the document, we have the
following comments concerning the proposed action items discussed in the plan. Fuel Storage and Dispensing Areas Registration and Compliance with Technical Standards In general, CDM
agrees with the proposed approach outlined for updating the registration documents for the underground storage tank (UST) systems in use at the airport and bringing the UST systems into
compliance with current and upcoming TNRCC technical standards. However, we have the following comments and recommendations concerning these action items. Registration CDM recommends
that the Town of Addison (Town) obtain a copy of each of the updated registration documents submitted to the Texas Natural Resource Conservation Commission (TNRCC) and any follow-up
correspondence that may be submitted for each of the fueling facilities discussed in the Action Plan in the event that a third party review is necessary. Based on the facilities listed
in the Plan of Action, and based on CDM's review ofTNRCC files and tenant interviews during the Phase I ESA, it appears that there may still be some confusion regarding Facility ID numbers
14509 and 15460. This may have been cleared up during the registration updating process performed by AATI and their consultant; however, CDM would need to review the submitted registration
forms to confirm this conclusion. The reason we think that there may still be some confusion regarding these Facility ID numbers is that the UST that was removed at Monarch Air is not
mentioned in the Action Plan under Facility ID number 14509. A UST was removed from this facility, but updated registration documents were not submitted once the tank was removed. Monarch
Air showed CDM the registration documents, but it does not appear that they were ever submitted to TNRCC. The registration for this facility also needs to be updated to show that the
tank has been removed. The Action Plan states that E.U.A. Air Support operates this facility. 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 2 Information reviewed by CDM during the ESA indicated that Monarch Air, not E.U.A, removed this tank. CDM also
recommends that the registration documents for the FAA (ATCT) be updated as discussed in the ESA to show that the UST was removed, not closed in place. CDM also recommends that AATIdetermine
if the tanks at the Texas Pro Air facility were ever registered and if the registration documents need to be updated to show that the tanks at this facility were removed. Technical Compliance
Standards COM recommends that the Town obtain copies of any deficiency letters that are submitted to the owner/operators by the TNRCC following their inspection of the fueling facilities
and any follow up correspondence that may be submitted by the involved parties. We further recommend that the Town request additional information from AATI that addresses the following:
I) How does AATI plan to monitor the operator's progress towards making any necessary upgrades to their fueling systems? How will AATI document that the upgrades are performed? Will
AATI inspect the facilities as the upgrades are performed by the tenants or will they rely on !he operators to document compliance? 2) Who will review and approve the suggested upgrade
or engineering modifications prior to installation? Since there are numerous tank monitoring, release detection and spill prevention systems on the market, it is our opinion that the
proposed system modifications should be reviewed and approved prior to installation to assure that they meet with everyones approval. 3) How will AATI acquire all necessary information
from tenants in a timely manner? 4) Who will be responsible for staying current with future UST regulations that might be promulgated and who will monitor and assure that future compliance
is maintained for these UST systems? 6) How will AATI keep the Town informed concerning the progress made towards compliance in this area? CDM recommends that the review and oversight
oversight of all the proposed upgrades be performed by an independent outside consultant familiar with fuel system design and modification that would be retained by the individual owner/operator,
AATI or the Town. Leaking Petroleum Storage Tank Corrective Actions In general, CDM agrees with the proposed approach outlined for the assessment of the Leaking Petroleum Storage Tank
Corrective Actions that were outlined in the Action Plan. Since the TNRCC is in charge of regulating releases from UST sites, they will direct, review and approve any assessment and/or
cleanup work that may be needed at each of these sites. They will also determine when closure, in accordance with regulatory standards, is appropriate. However, CDM has the following
comments and recommendations concerning this action item. COM recommends that the Town obtain copies of all correspondence and reports that are submitted between the owner/operators
and the TNRCC during the investigation, assessment and remediation of these sites. We further recommend that the Town request additional information concerning how 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 3 AATI will monitor the operator's progress in petforming the assessment and remedial work that may be required
at these sites to assure that they are assessed in a timely manner. Information should also be requested that addresses how AATI will keep the Town informed of the progress made concerning
the work petformed in these areas. Will AA TI provide direct oversight of the investigation/assessment work petformed by the tenants andlor review the reports submitted to the TNRCC
by the tenants? At a minimum, CDM recommends that all site investigation, assessment and remedial activities initiated at these sites be petformed by an independent third party environmental
consultant fiuniliar with TNRCC UST regulations and reporting requirements. The Town may also want to consider your own third party review of the reports prepared for submission to TNRCC,
oversight of the assessment activities petformed by tenants, review of remedial proposals, proposals, or limited confirmation sampling around all of the tank systems located in the fuel
farm area to assure that the Towns interests are protected. As discussed in the ESA, the Town may also want to consider more stringent cleanup requirements in the fuel farm area since
redevelopment of this area for other uses may be planned in the future. Spill Prevention, Control and Countermeasures Plan (SPCC) CDM recommends that the Town obtain copies of all correspondence
and reports that are submitted between AATI and the regnlatory agency. CDM also recommends that the Town request additional information on how AATI will keep the Town informed concerning
the development, approval and implementation of this plan. All tenants who operate fuel !'anns should be provided a copy of the plan and provided with adequate training in regards to
the implementation and execution requirements of the plan. CDM recommends that the SPCC plan be developed by a third party environmental consultant/engineer experienced in the development
and implementation of these types of spill plans. The Town may also want to consider their own third party review of the SPCc. Storm Water Management NPDES Permit Activities CDM recommends
that the Town obtain copies of all correspondence and reports that are submitted between AA TI and the regnlatory agency. CDM also recommends that the Town request additional information
on how AATI will keep the Town informed concerning the revisions to the tenants Notices of Intent and other work petformed in this area. CDM recommends that all training sessions and
meetings that are held with tenants concerning the NPDES Permit be documented to assure that adequate training is petformed concerning the implementation and execution requirements of
the plan. CDM recommends that all NPDES permitring activities be petformed by a tbird party environmental consultant familiar with these types of permits. The Town may also want to consider
their own third party review of the NPDES permitting activities petformed. SWPPP SWPPP Activities CDM recommends that the Town obtain copies of all correspondence and reports regarding
the development and implementation of the SWPPP and associated best management practices developed for the airport. CDM also recommends that tbe Town request additional information on
how AATI will keep the Town informed concerning the development, approval, and implementation of the SWPPP. CDM recommends that all tenants be provided with a copy of the plan and all
training sessions and meetings held with tenants concerning the SWPPP be documented to assure that adequate 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 4 training is performed concerning the implementation and execution requirements of the plan. CDM recommends that
the SWPPP be developed by a third party environmental consultant experienced in the development and implementation of these types of plans. The Town may also want to consider their own
third party review of the SWPPP. Aircraft Washing CDM agrees with the approach outlined in the plan to address aircraft washing. However, we feel that additional infonnation is needed
concerning how these requirements will be managed and enforced. This infonnation will likely be provided in the SWPPP. Floor Drains CDM recommends that the Town obtain copies of the
drainage study perfonned on the floor drains in the event a third party review is necessary. CDM also recommends that the Town request additional information on how AA TI will keep the
Town updated concerning the floor drain discharge modifications outlined in the plan. Exterior WastelChemical Storage Areas CDM recommends the Town request additional information concerning
how AATI will monitor and assure compliance in the exterior waste/storage areas. According to the plan, most tenants have now installed proper storage devices for these areas. CDM recommends
that additional infonnation be provided to the Town documenting the types and locations of the storage facilities that have been approved by AA TI and how they relate to the SWPPP. Will
these facilities be inspected by AA Tlon a regular basis to assure continued compliance? Have the waste materials identified in the ESA been removed? Are the approved waste storage areas
covered? Have spill containment devices been installed? CDM also recommends that the Town request additional information on how AATI will keep the Town informed of future inspections,
if ally, that will be performed in these areas. Once identified, the Town may also want to consider a third party inspection of these storage areas to assure their interests are protected.
Drainage Swales CDM agrees with the limited sampling plan proposed, however, the exact scope of work to be performed may change as the project progresses. Ifthe Town decides to move
forward with this investigation, CDM recommends that the Town obtain copies of all correspondence and reports regarding the investigation of the drainage swales. CDM also recommends
that the Town request additional information on how AATI will keep the Town informed of the assessment activities performed in these areas. The Town may also want to consider third party
oversight during any testing activities performed in the drainage swales by AATI or their consultant. CDM cannot agree with the proposed costs without additional detailed cost information
as further detailed in the Costs Summarized Section of this letter. Emergency Spill Response Plan CDM recommends that the Town obtain copies of all correspondence and reports regarding
the development and implementation of the Spill Response Plan. CDM also recommends that the Town request additional information on how AATI will keep the Town informed concerning tenant

CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 5 compliance andlor noncompliance with the plan. CDM recommends that all tenants be provided with a copy of the
plan and that all training sessions and meetings held with tenants concerning the Spill Response Plan be documented to assure that adequate training is perfonned in regards to the implementation
and execution requirements of the plan. CDM recommends that the Spill Response Plan be developed by a third party environmental consultant experienced in the development and implementation
of these types of spill plans. The Town may also want to consider their own third party review of the spill plan developed. Surface Spills and Stained Soils Priority 1 Sites See comments
in Leaking Petrolenm Storage Tank Corrective Actions Section of this letter. Priority 2 and 3 Sites General Comments Regarding all Priority 2 and :3 Sites: CDM recommends that the Town
obtain copies of all correspondence and reports regarding any assessment or cleanup perfonned in the surface spill/stained soils areas. CDM also recommends that the Town request additional
infonnation on how AATI will keep the Town informed concerning the assessment andlor cleanup work performed in each of these areas. Additional infonnation also needs to be provided on how tenant follow up
and compliance will be handled for tenant sites where AA TI will recommend that the tenant perfonn the environmental assessment. The Town may also want to consider a third party review
of reports, oversight of the assessment activities performed by AATI andlor tenants, or limited confinnation sampling to assure that the Towns interests are protected. At a minimum,
CDM recommends that a1l site investigation, assessment and remedial activities initiated at these sites be perfonned by an independent third party environmental consultant familiar with
TNRCC regulations regarding the reporting, assessment and remediation of these types of sites. Based on the review of the Action Plan, it appears that all of the small aboveground waste
oil storage tanks that were previously supplied for individual tenant use by AATI have been removed. Are new plans in place to address waste oil disposal activities by individual tenants?
Additional infonnation on these procedures should be requested from AATI. In general, CDM agrees with the approaches outlined for the investigation and assessment of the spill/stained
areas outlined in the plan with the following exceptions. Building 2 and 3 -Coop Hangers This environmental concern can probably be classified as a Priority 3 site based on CDM's observations
during the ESA. Building 29 -Walter Fuller Aircraft Sales Hanger and Maintenance Shop As stated in the Phase I ESA, CDM recommends that a limited surfaceisubsurface soil assessment be
performed in the location of the previous waste oil tank. 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 6 Building 31 -All American Aviation and Maintenance Hanger Since the impacted area between the hangers is small,
an alternati ve approach that the Town might want to consider would include performing the initial limited investigation as proposed, followed by excavation and clearance sampling consistent
with what AATI proposed for the COOP Hangers. Building 4 -300 Series Hanger As discussed in the Phase I ESA, CDM recommends limited sampling in hanger 320 where the large fuel spill
occurred. Based on photos reviewed, all staining did not appear to be on the impermeable surface. Building 8 -Skytech Aviation and Maintenance Shop As discussed in the Phase I ESA, CDM
also recommends limited testing beneath the waste oil storage tank at this facility. Building 19 -Henley's Aircraft Services Hanger and Maintenance Shop As discussed in the Phase I ESA,
CDM recommends limited testing beneath the ramp to determine if the soils have been impacted. Building No. 58 -Addison Aviation Services Hanger and Maintenance Shop CDM recommends that
limited subsurface testing be performed in these areas as discussed in the Phase IESA. Suspected Fill Areas Ifthe Town decides to move forward with this investigation, CDM agrees with
the limited sampling plan proposed, however, the exact scope of work to be performed and associated costs may change as the project progresses. CDM cannot agree with the proposed costs
without additional detailed cost information as further detailed in the Costs Summarized Section of this letter. CDM recommends that the Town obtain copies of all correspondence and
reports regarding any assessment or cleanup performed in the fill areas. CDM also recommends that the Town request additional information on how AATI will keep the Town informed concerning
the assessment and/or cleanup work performed in these areas. The Town may also want to consider a third party review of reports, oversight of the assessment activities performed by AATI
and/or or tenants, or limited confirmation sampling to assure that the Towns interests are protected. At a minimum, CDM recommends that all site investigation, assessment and remedial
activities initiated in the fill areas be performed by an independent third party environmental consultant familiar with TNRCC regulations regarding the reporting, assessment and remediation
of these types of sites. No information was provided concerning surface fill areas where dumping was observed in the Airfield Operations Area (AOA). Will surface dumping in the AOA be
allowed in the future or will policies be developed to assist in preventing further dumping in these areas? Iffill will continue, will anyone regulate the materials used as fill? Ifso,
how will this program be managed and what types of fill will be allowed. 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 7 Septic Tanks Ifthe Town decides to move forward with this investigation, CDM generally agrees with the limited
sampling plan proposed, however, the exact scope of work to be performed and associated costs may change as the project progresses. CDM cannot agree with the proposed costs without additional
detailed cost information as further detailed in the Costs Summarized Section of this letter. CDM recommends that the Town obtain copies of all correspondence and reports regarding any
assessment or cleanup performed in the septic tank areas. CDM also recommends that the Town request additional information on how AATI will keep the Town informed concerning the assessment
and/or cleanup work performed in each of these areas. Additional information also needs to be provided on how tenant follow up and compliance will be handled for tenant sites where AATI
will recommend that the tenant perform the environmental assessment of the septic tanks. The Town may also want to consider a third party review of reports, oversight of the assessment
activities performed by AATI and/or tenants, or limited confirmation sampling to assure that the Towns interests are protected. At a minimum, CDM recommends that all site investigation,
assessment and remedial activities initiated at these sites be performed by an independent third party environmental consultant familiar with TNRCC regulations regarding the reporting,
assessment and remediation of these types of sites. Other Areas Hydraulic Lifts What will happen if maintenance and repair records are not available for the systems identified? Since
other assessment activities are already being recommended by AATI to the tenant in the Six Hanger, it is our opinion that it would be cost effective for the tenant to perform additional
limited investigation in the vicinity of the hydraulic lift at the same time to document if a concern exists. Costs Summarized Based on the limited information provided in the Action
Plan concerning the exact scope of work to be performed and the questions presented in this document, CDM cannot effectively evaluate the investigation/assessment costs presented in
this Section of the Action Plan. CDM recommends that the Town decide which specific tasks they would like AA TI to begin addressing and request detailed work proposals, schedules and
cost estimates for this work. Once the exact scope of work is defined, AATI should be able to develop a detailed cost breakdown for each action item. The cost breakdown should include
estimated costs for labor, outside professionals/subcontract and other direct costs that would be required to complete the work, not just an estimated total dollar amount. CDM can then
compare these detailed cost breakdowns to industry standards to determine if they are reasonable. The Town may want to consider competitive bidding to assist in keeping costs for this
project in check, or having some of the work performed under the direction of the Town so that costs can be be more closely monitored by Town staff. General Comments CDM recommends that
the Town assure that someone is reviewing the qualifications and experience of the environmental consultants that will be used by the tenants and AATI. Since the experience and 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 12, 1998 Page 8 qualifications of finns vary widely and this is an important project to the Town, COM recommends that the qualifications
and experience of these firms be closely scrutinized. Iftheir are any discrepancies identified between the recommendations provided in this letter and the original ESA performed by COM,
the recommendations provided in the ESA will govern. COM appreciates the opportunity to provide this review to the Town of Addison. If you have any questions regarding this infonnation
presented or need any additional information, please phone me at 214-346-2800. Sincerely, CAMP ORESSER & McKEE INC. Ron Hartline, P .E. Project Manager RH:kar 
__________________________ _ JOB NO.VATE ArrENTfON RE:Public Works I Engineering 16801 Westgrove' P.O. Box 144 Addison, Texas 75001 Telephone: (214) 450-2871 • fox: (214) 931·6643 GENTLEMAN:
WE ARE SENDING YOU 􀁾􀁴􀁴􀁡􀁣􀁨􀁥􀁤􀀠D Under separate cover via ______the following items: D Shop Drawings 'r}Prints D Plans D Samples D Specifications D_________________________D Copy
of letter D Change order COPIES DATE NO. DESCRIPTION 􀁾􀀠OAllJ//A J--u IA,:I-L C'.h d' b 􀁨􀀱􀀻􀀻􀀻􀁾􀀠(/• I I (j I 1.6-8-1K-" THESE ARE TRANSMITTED as checked below: D For approval
D Approved as submitted D Resubmit ____copies for approval }(For your use D Approved as noted D Submit copies for distribution D As requested D Returned for corrections D Retum corrected
prints D For review and comment D D FOR BIDS DUE __________ 19,____ D PRINTS RETURNED AFTER LOAN TO US REMARKS _______________________________________________________ COpy TO ________________________
____ If enclosures are not as noted, pleas no' us at once. 
___________________________ _ --ADDisoN Public Works I Engineering 16801 Westgrove. P.O. Box 144 Addison, Texas 75001 Telephone: (214) 450-2871 • Fax: (214) 931·6643 DATE JOB NO. ATTENTION
GENTLEMAN: WE ARE SENDING YOU p(f.ttached o Under separate cover via ______ the 􀁦􀁯􀁬􀁬􀁯􀁾􀁩􀁮􀁧􀀠items: o Shop Drawings o Prints o Plans 0 Samples 0 Specifications 0 __________________________o
Copy of letter o Change order DESCRIPTIONNO.COPIES DATE ...-.. f'􀁾4'-J 􀁾.....'" J.£.-, (;";/;;: //lA /AJ "/h rr--'t (/(J '-"?I ( I THESE ARE TRANSMITTED as checked below: o For approval
0 Approved as submitted o Resubmit _____ copies for approval p(ior your use 0 Approved as noted o Submit copies for distribution o As requested 0 Returned for corrections o Return corrected
prints o For review and comment 0 o FOR BIDS DUE ___________________ 19____ o PRINTS RETURNED AFTER LOAN TO US REMARKS ______________________________________________________________________
COPYTO __________________________________ SIGNED: 􀀭􀀬􀁌􀁾􀁾􀁾􀁾􀁾􀁾􀀺􀀺􀀺􀀺􀀽􀀺􀀺􀀢􀀺􀀺􀀺􀀺􀀺􀀽􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭If enclosures are not as noted, please 
CDM Camp Dresser & McKee Inc. consulting engineering construction opera,ons One Glen Lakes 8140Walnut Hill 􀁾􀁡􀁮􀁥􀀬􀀠Suite 1000 Dallas, Texas 75231 Tel: 214 346·2800 Fax: 214 987·2017
June 1, 1998 Mr. Jim Pierce, P.E. Project Manager Town of Addison P.O. Box 144 Addison, Texas 75001-0144 Re: Amendment 1 to Engineering Services Agreement between Camp Dresser & McKee
Inc. and the Town of Addison for Phase I Environmental Site Assessment Services at Addison Airport Dear Mr. Pierce: The Phase I Environmental Site Assessment (ESA) of Addison Airport
has been completed by Camp Dresser & McKee Inc. (COM) in accordance with our previous contract. Since the ESA was completed, Addison Airport of Texas Inc. (AATI) has developed a Plan
of Action to address the environmental concerns identified in the ESA. The Town of Addison would now like COM to review the Plan of Action and provide our comments concerning the proposed
assessment, oversight, and management activities discussed in the plan. To facilitate our review of these documents, CDM will need to amend our current contract upper limit. The labor
budget for the previous contract has been expended and will require an amendment to allow COM to complete the requested services. COM proposes to review the Addison Airport Plan of Action
and provide our comments to each of the proposed action items in a follow up letter to the Town of Addison. COM has also included one meeting with Town staff upon completion of the review
activities. A second meeting has also been included, ifneeded, with Town staff, AATI and AATI's environmental consultant to discuss any additional information that may be needed or deficiencies
identified in the proposed plan. Project Budget COM proposes to increase the upper limit for this project as presented below. All services outlined in this amendment will be performed
in accordance with the terms and conditions of our original contract. Review Action Plan and Compare to ESA Findings (10 hours at $ 90.00/hour) ...........................................
$ 900.00 Prepare Written Response to Plan of Action (10 hours at $ 90.00/hour) . . .. $ 900.00 Meet with Town of Addison to Discuss Response Findings (4 hours at 90.00/hour) .........................
.................... $ 360.00 Ifneeded, Meet with Town and AATI to Discuss Response Findings (4 hours at $ 90.00/hour) ............................................ $ 360.00 Administration/Clerical
Services (5 hours at $ 45.00/hour) .............. $ 225.00 Total Amendment Requested ...................................... $ 2,745.00 
CDM Camp Dresser & McKee Inc. Mr. Jim Pierce, P.E. June 1, 1998 Page 2 Schedule CDM proposes to complete the services described in this amendment within 14 days of receipt of written
authorization from the Town of Addison. CDM appreciates the opportunity to provide continued service to the Town of Addison. If you have any questions about this amendment or need any
additional information, please phone me at 214-346-2800. Sincerely, CAMP DRESSER & McKEE INC. 􀁾􀁾􀁃􀀮􀀱􀁫􀁊􀁁􀁾􀀮􀀠Ron Hartline, P.E. c. Hunter Nolan Y1(.11. Project Manager Vice President
APPROVED: TOWN OF ADDISON DATE (r,z...-!' -9'P 
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