PHASE II ENVIRONMENTAL SITE ASSESSMENT BURKHART ESTATE MATAGORDA COUNTY, TEXAS

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1 FINAL REPORT PHASE II ENVIRONMENTAL SITE ASSESSMENT BURKHART ESTATE MATAGORDA COUNTY, TEXAS PREPARED FOR: TEXAS A&M UNIVERSITY PREPARED BY: AUSTIN, TEXAS MAY 26, 2011

2 1.0 EXECUTIVE SUMMARY A Phase II Environmental Site Assessment (ESA) was completed during April and May 2011 by URS Corporation (URS) on behalf of Texas A&M University (TAMU) at the Burkhart Estate in Matagorda County, Texas. Areas of investigation were selected based on the results of the March 2011 Phase I ESA, which documented recognized environmental conditions apparently related to oil and gas production and associated brine injection activities at the site. The Phase II sampling activity included advancing 22 soil borings, installing five temporary groundwater sampling points, and sampling four existing site water wells. A total of 31 soil samples and eight groundwater grab samples were collected during the investigation and analyzed variously for total petroleum hydrocarbons (TPH), volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), metals (arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver), select cations (calcium, magnesium, potassium, and sodium), select anions (chloride and sulfate), alkalinity, total dissolved solids (TDS), ph, and/or specific conductance. Analytical results were screened using the lowest applicable Tier 1 residential protective concentration level (PCL) for each chemical of concern (COC), assuming a 30-acre source area (site-specific) and Class 1 groundwater (default), based on the Texas Risk Reduction Program (TRRP) rule (Texas Administrative Code [TAC], Title 30, Part 1, Chapter 350). The presence of contamination above the applicable PCLs was confirmed in multiple areas of the investigation, indicating release(s) of hazardous substances or petroleum products. URS concludes that the recognized environmental conditions appear to be related to oil and gas production and associated brine injection activities at the Burkhart Estate, and recommends that TAMU report the findings of this Phase II ESA to the Site Remediation Section of the Oil and Gas Division of the Railroad Commission (RRC) of Texas. 2.0 INTRODUCTION 2.1 Purpose Referring to guidance from the American Society for Testing and Materials (ASTM), the primary objectives of conducting a Phase II Environmental Site Assessment (ESA) are to evaluate the recognized environmental conditions identified in the Phase I ESA for the purpose of providing sufficient information regarding the nature and extent of contamination to assist in making informed business decisions about the property; and where applicable, providing the level of knowledge necessary to satisfy the innocent purchaser defense under the Comprehensive Environmental Response, Compensation, and Liabilities Act (CERCLA). Accordingly, the extent of the assessment is based on the business objectives of the user as well as the degree of uncertainty acceptable to the user. Therefore, it may be appropriate to perform more than a single iteration of assessment to satisfy the objectives of the user; however, many Phase II ESAs are in fact restricted to only a single round of assessment. Prior to conducting Phase II ESA activities, URS Corporation (URS) discussed with Texas A&M University (TAMU) the project objectives and degree of uncertainty that is acceptable to TAMU, as well as the appropriate scope of work to satisfy those objectives. Subsequently, URS conducted the agreed upon single iteration of soil and groundwater field investigations to screen the site for the presence or absence of contamination potentially related to oil and gas production and associated brine injection activities at the site. The results of the Phase II ESA are presented in this report. 2.2 Limitations This report and the associated work have been provided in accordance with the principles and practices generally employed by the local environmental consulting profession. This is in lieu of all warranties, expressed or implied. It should be recognized that this study was not intended to be a definitive investigation of the nature and extent of contamination at the subject property, and the recommendations provided are not necessarily inclusive of all the possible conditions. This Phase II ESA is not a regulatory compliance audit or an evaluation of the efficiency of the use of any hazardous materials at the subject property. The assessment did not include a survey for Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 1 May 26, 2011

3 wetlands or naturally occurring radioactive materials (NORM). Additionally, sampling for asbestos, radon, and lead-based paint was not performed. Given that the scope of work for this investigation was limited, it is possible that currently unrecognized contamination may exist at the site. The conclusions presented in this report are professional opinions based solely upon indicated data described in this report. URS does not assume any liability for information that has been misrepresented to us by others or for items not visible, accessible, or present on the subject property during the time of the investigation. The conclusions and recommendations are intended exclusively for the purpose outlined herein and for the site location and project indicated. This Phase II ESA report has been prepared for use by TAMU. This report shall not be relied upon by or transferred to any additional parties, or used for any other purpose, without the express written authorization of URS. Opinions and recommendations presented herein apply to the site conditions existing at the time of our investigation and cannot necessarily apply to site changes of which URS is not aware and has not had the opportunity to evaluate. Changes in the conditions of this property may occur with time due to natural processes or the works of man on the subject site or adjacent properties. Changes in applicable standards may also occur as a result of legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated, wholly or in part, by changes beyond our control. Opinions and judgments expressed herein are based on URS understanding and interpretation of current regulatory standards, and should not be construed as legal opinions. 3.0 BACKGROUND In March 2011, URS completed a Phase I ESA on behalf of TAMU at the Burkhart Estate in Matagorda County, Texas. The site consists of approximately 2,903 acres of contiguous property located approximately 4 miles northwest of Bay City, Texas, on the western bank of the Colorado River. The mostly undeveloped property is primarily used for cattle ranching, oil and gas development, and pipeline routing. During Phase I ESA activities, recognized environmental conditions were observed that are apparently related to oil and gas production and associated brine injection activities at the site, and the need for conducting a Phase II ESA was confirmed. The Phase I ESA Final Report provides additional information regarding the site description and features, its physical setting, site history and land use, adjacent property land use, and the assessment s findings. A map depicting the general location of the Burkhart Estate relative to Bay City, Texas, is provided as Figure PHASE II ACTIVITIES 4.1 Areas of Investigation Based on the objectives and the degree of acceptable uncertainty that was defined by TAMU, URS conducted a single iteration of soil and groundwater field investigations to screen the Burkhart Estate for the presence or absence of contamination related to past or present site operations. Areas of investigation were selected based on the results of the Phase I ESA, which identified 23 potential sources of hazardous or petroleum substances, and through discussions of the Phase I findings with TAMU. The resulting work plan prioritized seven key areas for investigation that are summarized in the following table. Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 2 May 26, 2011

4 Areas Investigated During Phase II ESA Area J Northeastern saltwater injection system, brine pond, and related aboveground storage tanks (ASTs). Area K Northeastern oil ASTs and heater treater facility (northeastern property boundary at Colorado River). Area O Saltwater spill/drainage area. Area P Western heater treater facility. Area Q Abandoned drilling mud pits. Area S Western saltwater injection system, brine pond, and related ASTs. Area T Area east of off-site crude oil tanks (western property boundary at County Road 408). Four additional areas were investigated utilizing select existing site water wells summarized in the table below. Area D Area E Area M Area R Water Wells Investigated During Phase II ESA Windmill water well, active (in use), depth unknown. Residential water well, active (ready for use), depth unknown. Water well adjacent to abandoned compressor station, inactive (pump disconnected), depth unknown (measured >100'). Residential water well, active (ready for use), depth unknown. A map depicting the areas of potential environmental concern that were selected for investigation is provided as Figure Scope of Work The Phase II ESA consisted of planning and site reconnaissance, soil and groundwater sampling and analysis, and documenting findings and recommendations in this report. Planning involved the necessary management, contracting, and scheduling steps to safely execute the field investigation. Site reconnaissance was conducted to identify candidate water supply wells for sampling; to stake/mark the proposed soil and groundwater sampling locations; and to coordinate underground utility clearances with a private utility locator and various pipeline representatives. The sampling activity consisted of retaining and overseeing a driller to advance 22 soil borings and install five temporary groundwater sampling points to depths ranging from 15 to 35 feet using direct push technology (DPT) equipment. Drilling locations were selected to target potential releases related to the oil and gas production or brine injection equipment, or other site features, present within the areas described above. Access to some equipment was precluded by fencing, above-ground piping and structures, and/or underground pipelines. Therefore, most soil borings had to be placed around the periphery of potential points of release; but an effort was made to site the borings as close as possible to their intended targets so as to obtain, to the extent practicable, a representative sampling of each investigation area. A total of 31 soil samples and four groundwater grab samples were collected during the drilling activity (one of the temporary groundwater sampling points did not produce water). Additionally, groundwater grab samples were also collected from four select existing site water wells described above. During the field sampling activity, a photoionization detector (PID) and radiation meter were utilized for safety monitoring and sample screening purposes. Investigation-derived waste (IDW) soil was placed inside a single 55-gallon drum that is presently staged at Area K, pending removal. Soil and groundwater samples were submitted to a Texas-accredited laboratory for total petroleum hydrocarbons (TPH) analysis to evaluate potential site impacts related to past or present oil and gas operations. Groundwater samples were also analyzed for select cations (calcium, magnesium, potassium, and sodium), select anions (chloride and sulfate), alkalinity, total dissolved solids (TDS), ph, and specific conductance to Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 3 May 26, 2011

5 evaluate site impacts related to previous brine spills. Additionally, based on field observations, four soil and five groundwater samples were analyzed for volatile organic compounds (VOCs); four soil and three groundwater samples were analyzed for semi-volatile organic compounds (SVOCs); and 12 soil and two groundwater samples were analyzed for metals (arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver). One inconsequential deviation from the work plan was that the laboratory inadvertently analyzed two groundwater samples (O-03-GW-010 and Q-02-GW-010) for VOCs instead of TPH. Upon receiving the final laboratory data, a URS chemist reviewed it for completeness and to ensure its suitability for use in the Phase II ESA report. Maps of specific sampling locations are provided as Figures 3 and 4. Summaries of soil and groundwater analyses completed for each sample are provided in the following tables. Soil Analysis Summary Sample ID Depth TPH VOCs SVOCs Metals Sample ID Depth TPH VOCs SVOCs Metals J ' X O ' X X J ' X X P ' X J ' X P ' X J ' X P ' X J ' X Q ' X X K ' X Q ' X K ' X X X X Q ' X X K ' X Q ' X X K ' X S ' X K ' X X X X S ' X K ' X S ' X X X X K ' X S ' X X X X K ' X S ' X O ' X X S ' X O ' X X S ' X O ' X X Groundwater Analysis Summary Sample ID TPH VOCs SVOCs Metals Cations Anions Alk TDS ph SC O-03-GW-010 X X X X X X X Q-02-GW-010 X X X X X X X S-02-GW-010 X X X X X X X X X T-01-GW-013 X X X X X X X Well-E-010 X X X X X X X X X X Well-M-010 X X X X X X X X X X Well-R-010 X X X X X X X WellWM-D-010 X X X X X X X 5.0 EVALUATION AND PRESENTATION OF RESULTS 5.1 Site Geology Subsurface conditions throughout the site vicinity are mapped and described in the Texas Water Development Board s Geologic Atlas of Texas, Seguin Sheet (1979) and Houston Sheet (1982). According to the atlas, roughly the northeastern half of the Burkhart Estate is underlain by Quaternary (Holocene) age alluvium (clay, silt, and Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 4 May 26, 2011

6 sand) associated with the adjacent Colorado River and its tributaries. The southwestern portion of the site is underlain by somewhat older Quaternary (Pleistocene) age fluvial deposits (mostly clay) known as the Beaumont Formation, which may be approximately 100 feet thick. Beneath the Beaumont lie the Lissie Formation (approximately 200 feet thick) and Willis Formation (up to 75 feet thick), which complete a vertical sequence of predominantly fluvial Quaternary age sediments collectively referred to as the Chicot unit of the regional Gulf Coast aquifer. Observations at 22 soil borings drilled and sampled during the Phase II ESA confirm the presence of clay, silt, and sand mixtures within the upper 15 to 35 feet of site geologic materials. A brief summary of soil conditions and geologic materials logged at each sampling location is provided in the table below. In addition, copies of the State of Texas Well Reports are included in Appendix 1. Soil Log Summary Loc Depth Description J ' Mostly silt and clay w/sand, brown. Gray-brown at 12'. J ' Mostly silt and clay w/sand, brown. Black at 7', reddish-brown at 10'. J ' Mostly silt and clay w/sand, brown. Black at 3', brown at 5', reddish-brown at 9'. J ' Mostly silt and clay w/sand, brown. Black at 5', gray-brown at 8', reddish-brown at 10'. J ' Mostly silt and clay w/sand, brown. Dark gray at 5', reddish-brown at 10'. K ' Mostly silt and clay w/sand, brown. Black at 9', reddish brown at 12'. Mostly silt and clay w/ sand, brown. Reddish brown sand at 19.5', wet clayey silt at 25'. K ' Temporary well installed, screened 25-35'. Well dry. K ' Mostly silt and clay w/sand, brown. Black at 10', reddish brown at 11'. K ' Mostly silt and clay w/sand, brown. Black at 10', reddish brown at 11'. O ' Mostly silt and clay w/sand, brown. Black at 5', dark gray at 6.5', reddish-brown at 10'. O ' Mostly silt and clay w/sand, brown. Black at 6', gray-brown at 8', reddish-brown at 10'. Mostly silt and clay w/ sand, brown. Light brown sand at 20', wet silty clay at 23'. Temporary O ' well installed, screened 18-28'. Depth to water was 22.35'. P ' Mostly sandy clay, brown. Greenish gray clayey sand at 5', wet sand at 15'. P ' Mostly sandy clay, brown. Tan sand at 6.5', damp to wet sand at 10'. Q ' Mostly silt and clay w/ sand, brown. Light gray sand at 13.5'. Mostly silt and clay w/ sand, brown. Tan sand at 11', wet sand at 19'. Temporary well installed, Q ' screened Depth to water was 18.70'. S ' Mostly sandy clay, brown. Black and wet at 2', reddish-brown sand at 8.5', wet sand at 11.5'. Mostly sandy clay, brown. Brown sand at 9.5', wet sand at 16', clay at 25'. Temporary well S ' installed, screened 18-28'. Depth to water was 15.05'. S ' Mostly sandy clay, brown. Yellow-brown sand at 11.5', damp to wet sand at 15'. S ' Mostly sandy clay, brown. Reddish-brown sand at 10', damp sand at 15'. S ' Mostly sandy clay, brown. Reddish brown sand at 8.5', damp to wet sand at 13'. Mostly silt and clay, brown and gray. Wet sand at 17.5', clay at 20'. Temporary well installed, T ' screened 13-23'. Depth to water was 12.05'. 5.2 Soil Analytical Results As outlined above in Section 4.0, a total of 31 soil samples were collected from 22 soil borings distributed throughout Areas J, K, O, P, Q, and S, and were analyzed for TPH, VOCs, SVOCs, and/or metals. The appropriate benchmark for screening analytical results is the lowest applicable Tier 1 residential protective concentration level (PCL) for each chemical of concern (COC), assuming a 30-acre source area (site-specific) and Class 1 groundwater (default), based on the Texas Risk Reduction Program (TRRP) rule (Texas Administrative Code [TAC], Title 30, Part 1, Chapter 350). Soil COCs were detected at each area of investigation, but only a total of 16 Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 5 May 26, 2011

7 samples were found to have at least one COC above an applicable PCL. All soil PCL exceedances are summarized in the following table. PCL Exceedances in Soil Sample ID Depth Analyte Result PCL (mg/kg) (mg/kg) PCL Reference J ' Lead TX Background Selenium Soil -Ing K ' TPH GW- Soil -Ing K ' TPH Soil -Ing Selenium Soil -Ing K ' TPH GW- Soil -Ing K ' TPH Soil -Ing Selenium Soil -Ing K ' TPH GW- Soil -Ing O ' Lead TX Background Selenium Soil -Ing Arsenic TX Background Barium TX Background O ' Lead TX Background Mercury TX Background Selenium GW- Soil -Ing Arsenic TX Background O ' Lead TX Background Selenium GW- Soil -Ing O ' Selenium GW- Soil -Ing Q / ' Selenium 4.22 / GW- Soil -Ing Q ' Barium TX Background Selenium Soil -Ing S / ' TPH 6260 / GW- Soil -Ing S ' TPH GW- Soil -Ing TPH / GW- Soil -Ing S / ' 2-Methylnaphthalene 23.6 / Soil -Ing Naphthalene (SW8260C) 18.3 / Soil -Ing Selenium 1.59 / GW- Soil -Ing TPH GW- Soil -Ing 1,2,4-Trimethylbenzene GW- Soil -Ing 2-Methylnaphthalene GW- Soil -Ing S ' Benzene Soil -Ing Ethylbenzene Soil -Ing Naphthalene (SW8260C) GW- Soil -Ing Naphthalene (SW8270D) GW- Soil -Ing Selenium GW- Soil -Ing Additional soil data tables that summarize all detections of metals, VOCs, SVOCs, and TPH, and their screening criteria, are included in Appendix 2. A copy of the final laboratory analytical report is included in Appendix 3. Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 6 May 26, 2011

8 5.3 Groundwater Analytical Results As outlined above in Section 4.0, a total of four groundwater grab samples were collected from temporary monitoring points at Areas O, Q, S, and T, and four grab samples were collected from select existing site water wells D, E, M, and R. The samples were analyzed for TPH, VOCs, SVOCs, and/or metals for comparison to the appropriate PCLs, and for select cations and anions, alkalinity, TDS, ph, and specific conductance, which are not regulated by TRRP but are useful in documenting general water quality and variability. Again, the lowest applicable TRRP Tier 1 PCL for each COC was used as a benchmark. Groundwater COCs were generally not present in most of the samples, but one temporary monitoring point (S-02) was found to have two COCs above the applicable PCLs. Summaries of the S-02 groundwater PCL exceedances and the non-regulated water quality parameters from all sample points are provided in the tables below. Sample ID S-02-GW-010 PCL Exceedances in Groundwater Analyte Result PCL (mg/l) (mg/l) TPH Methylnaphthalene PCL Reference GW- GW -Ing GW- GW -Ing Water Quality Parameters Sample ID Cations (mg/l) Anions (mg/l) Alk TDS SC ph Ca Mg K Na Cl SO4 (mg/l) (mg/l) (µmhos/cm) O-03-GW Q-02-GW S-02-GW T-01-GW Well-E-010 / 89.4 / 25.8 / 1.78 / 89.2 / 167 / 13.5 / 318 / 601 / 7.34 / dup / 1030 Well-M Well-R WellWM-D Additional groundwater data tables that summarize all detections of metals, VOCs, SVOCs, and TPH, and their screening criteria, are included in Appendix 2. A copy of the final laboratory analytical report is included in Appendix DISCUSSION OF FINDINGS AND CONCLUSIONS 6.1 Findings from Each Area of Investigation During the Phase I ESA conducted during March 2011, URS found the presence or likely presence of hazardous substances or petroleum products at the Burkhart Estate apparently related to past or present oil and gas production and associated brine injection activities at the site. Having subsequently completed a Phase II ESA targeting the key areas defined and described by this report, URS has confirmed the presence of contamination above the applicable screening PCLs at five of seven areas where soil was investigated (Areas J, K, O, Q, and S), at one of five temporary groundwater monitoring points (Area S), and at none of four select existing water wells that were sampled. The findings from each area are discussed further below. Area J: The northeastern saltwater injection system, brine pond, and related ASTs were investigated via five soil samples collected at five different borings distributed throughout this approximately 2-acre area. TPH was detected in three out of the five samples, but at levels below applicable PCLs. One sample (J ) collected east of the brine pond at a depth of 7.5 to 8 feet was also analyzed for metals. While TPH was not detected in this sample, lead and selenium were detected above their respective PCLs. The lead result of 16.2 mg/kg is just Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 7 May 26, 2011

9 above its PCL of 15 mg/kg (the Texas-specific median background concentration), and therefore may be attributable to background lead concentrations in soil. The selenium result of 4.46 mg/kg, however, is about four times above its PCL of 1.1 mg/kg. Additionally, it is an order of magnitude above the median background concentration of 0.3 mg/kg, and is among the highest detections of selenium anywhere on site. Therefore, selenium levels in this area may be attributable to past release(s) of brine from the injection system, or otherwise may indicate that unusually high background selenium concentrations are present in site soil. Area K: The northeastern oil ASTs and heater treater facility were investigated via eight soil samples collected at four different borings distributed along the northern and eastern perimeter of this approximately 1-acre area. TPH was detected in six out of the eight samples, and five of the detections exceed applicable PCLs, ranging between 439 and 2910 mg/kg. Two samples (K and K ) collected north of the heater treater facility at depths of 9.5 to 10 feet and 27 to 27.5 feet, respectively, were also analyzed for VOCs, SVOCs, and metals. A few VOCs and SVOCs were detected in both samples, but at levels below applicable PCLs. Selenium was detected in both samples at levels a little more than two times above its PCL. While it is not clear whether selenium in this area is attributable to past brine release(s), or unusually high background concentrations, it appears that petroleum hydrocarbons have impacted Area K to a depth of at least 27.5 feet, and may have migrated north and northeast of the area in the direction of the Colorado River. Additionally, it should be noted that a temporary groundwater monitoring point was set at location K-02, screened between a depth of 25 and 35 feet; however, the well failed to yield groundwater. This result was unexpected because wet materials were observed in the soil core from a depth of 25 feet. Therefore, it is assumed that some kind of complication, either in selecting the appropriate screen interval or in physically setting the well, precluded groundwater collection at this location. Area O: The saltwater spill/drainage area was investigated via four soil samples collected at two different borings located about 180 feet apart within the wet-weather creek channel (dry at the time of sampling) where the spill apparently accumulated as documented in the Phase I ESA report. TPH was detected in one out of the four samples, but at levels below applicable PCLs. All four samples were also analyzed for metals with results for arsenic, barium, lead, mercury, and selenium each exceeding their respective PCLs in at least one sample. Maximum concentrations found in this area are 468 mg/kg for barium, 22.2 mg/kg for lead, and mg/kg for mercury detected in sample O from a depth of 0 to 0.5 feet; and 9.67 mg/kg for arsenic and 4.78 mg/kg for selenium detected in sample O from a depth of 3 to 3.5 feet. The levels of arsenic, barium, lead, and mercury are roughly 1.5 times above their respective PCLs, while the selenium result is about four times above its PCL. These results are among the highest detections of metals anywhere on site, and may therefore be attributable to release(s) of brine from Area J, as well as natural processes related to the perennial drainage feature. Additionally, one temporary groundwater monitoring point was installed within the channel at location O-03, approximately 1200 feet downstream of the soil borings. The well was screened between a depth of 18 and 28 feet and the depth to groundwater measured at the time of sampling was feet. The groundwater grab sample was analyzed for VOCs and water quality parameters. Acetone and benzene were detected, but at levels below applicable PCLs (acetone is a common laboratory contaminant, and the benzene result of mg/l was flagged J [estimated] and is an order of magnitude below its PCL of mg/l). Water quality parameters, Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 8 May 26, 2011

10 however, indicate that the groundwater at O-03 is distinctly different from groundwater tested elsewhere on site. Results for calcium (424 mg/l), magnesium (347 mg/l), sodium (1180 mg/l), chloride (4150 mg/l), TDS (8120 mg/l), and specific conductance (10200 µmhos/cm) are all about an order of magnitude greater than results from other site sampling points. While there are no PCLs applicable to these parameters, they are indicative of general water quality and, in this case, overall salinity. As such, the groundwater results appear to corroborate the metals results in soil, indicating that the wet-weather creek channel and underlying groundwater may be impacted by past brine release(s) from Area J. Area P: The western heater treater facility was investigated via three soil samples collected at two different borings located at the northern and eastern corners of this approximately 0.75-acre area. TPH was detected in one out of the three samples, but at levels below applicable PCLs. Therefore, this area does not appear to have been significantly impacted by petroleum hydrocarbons at the locations tested. Area Q: The abandoned drilling mud pits were investigated via four soil samples collected at two different borings located on the northwestern side and eastern corner of this approximately 1-acre area. TPH was not detected in any of the samples. Three samples were also analyzed for metals. Selenium was detected above its PCL in one sample (Q ) at a depth of 8.5 to 9 feet, and barium and selenium were detected above their PCLs in another sample (Q ) at a depth of 4.5 to 5 feet. The highest selenium result of 4.31 mg/kg from Q is about four times above its PCL of 1.1 mg/kg, and is among the highest detections of selenium anywhere on site. Likewise, the barium result of 418 mg/kg is considerably higher than its PCL of 300 mg/kg, and is the second highest barium detection anywhere on site. While these results are generally inconclusive, metals levels at Area Q may possibly be attributable to past drilling operations. Additionally, one temporary groundwater monitoring point was installed at location Q-02. The well was screened between a depth of 20 and 30 feet and the depth to groundwater measured at the time of sampling was feet. The groundwater grab sample was analyzed for VOCs and water quality parameters. Acetone was detected, but at levels below applicable PCLs (acetone is a common laboratory contaminant). Water quality parameters indicate that aside from having the highest alkalinity measured anywhere on site (495 mg/l), the groundwater at Q-02 is similar to groundwater tested elsewhere on site; therefore, it does not appear to be adversely impacted as a result of previous land use. Area S: The western saltwater injection system, brine pond, and related ASTs were investigated via seven soil samples collected at five different borings distributed throughout this approximately 1.5-acre area. TPH was detected in four out of the seven samples, and all of the detections exceed applicable PCLs, ranging between 2030 and mg/kg. Two samples (S and S ) collected just west of the injection well at depths of 11 to 11.5 feet and Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 9 May 26, 2011

11 15.5 to 16 feet, respectively, were also analyzed for VOCs, SVOCs, and metals. A few VOCs and SVOCs were detected in both samples, including various detections that exceed applicable PCLs. The greatest PCL exceedances occurred within the sample with the highest TPH result of mg/kg (S ): benzene (0.171 mg/kg flagged J [estimated]), 1,2,4-trimethylbenzene (49.1 mg/kg), ethylbenzene (14.0 mg/kg), naphthalene (35.5 mg/kg), and 2-methylnaphthalene (44.2 mg/kg). These results are roughly 2 to 13 times above their respective PCLs. Selenium was the only metal detected above its PCL in both samples. The highest selenium result of 4.53 mg/kg is about four times above its PCL of 1.1 mg/kg. Additionally, it is an order of magnitude above the median background concentration of 0.3 mg/kg, and is among the highest detections of selenium anywhere on site. Therefore, selenium levels in this area may be attributable to past release(s) of brine from the injection system, or otherwise may indicate that unusually high background selenium concentrations are present in site soil. In any case, it appears that petroleum hydrocarbons have impacted Area S to a depth of at least 16 feet. Additionally, one temporary groundwater monitoring point was installed at location S-02. The well was screened between a depth of 18 and 28 feet and the depth to groundwater measured at the time of sampling was feet. The groundwater grab sample was analyzed for TPH, VOCs, SVOCs, and water quality parameters. TPH and various VOCs and SVOCs were detected, but only TPH and 2- methylnaphthalene were detected above their applicable PCLs. The TPH result of 12.2 mg/l is about 12 times above its PCL of 0.98 mg/l, and the 2- methylnaphthalene result of mg/l is about 1.4 times above its PCL of mg/l. Water quality parameters indicate that the groundwater at S-02 is similar to groundwater tested elsewhere on site. Nonetheless, the groundwater TPH result appears to corroborate the TPH, VOCs, and SVOCs results in soil, indicating that Area S has been impacted by petroleum hydrocarbons. Area T: The area east of off-site crude oil tanks was investigated via one temporary groundwater monitoring point installed at location T-01. The well was screened between a depth of 13 and 23 feet and the depth to groundwater measured at the time of sampling was feet. The groundwater grab sample was analyzed for TPH and water quality parameters. TPH was not detected, and water quality parameters indicate that aside from having the highest sulfate measured anywhere on site (69.0 mg/l), the groundwater at Q-02 is similar to groundwater tested elsewhere on site; therefore, it does not appear to be adversely impacted as a result of offsite land use. Areas D, E, M, and R: Groundwater grab samples were analyzed from select existing site water wells to determine if they are currently impacted by past or present site operations. Evidence indicates that these wells are considerably deeper than the temporary groundwater monitoring points installed and tested elsewhere on site as part of the investigation (it was only possible to gauge one well [Well M], which measured greater than 100 feet deep [the limit of the measuring probe]). Therefore, results from the water wells are presumed to be representative of a different and separate groundwater zone than that which has been discussed thus far. Samples from windmill Well D and residential Well R were analyzed for TPH and water quality parameters. Samples from residential Well E and inactive Well M were analyzed for TPH, VOCs, SVOCs, metals, and water quality parameters. TPH was not detected in any of the samples, and water quality parameters indicate general similarities among the wells with no unusual outliers or other concerns. Acetone and bis(2-ethylhexyl)phthalate were the only VOC and SVOC detected, but at levels below applicable PCLs (acetone is a common laboratory Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 10 May 26, 2011

12 contaminant, and phthalates are a common field and laboratory contaminant). Metals results were all below applicable PCLs. Therefore, none of the water wells tested appear to be adversely impacted as a result of onsite or off-site land use. 6.2 Conclusions Referring to ASTM guidance, the term recognized environmental conditions means the presence or likely presence of any hazardous substances or petroleum products on a property under conditions that indicate an existing release, a past release, or a material threat of a release of any hazardous substances or petroleum products into structures on the property or into the ground, groundwater, or surface water of the property. The term includes hazardous substances or petroleum products even under conditions in compliance with laws. The term is not intended to include de minimis conditions that generally do not present a threat to human health or the environment and that generally would not be the subject of an enforcement action if brought to the attention of appropriate governmental agencies. Conditions determined to be de minimis are not recognized environmental conditions. Based on this understanding, and on the findings of the Phase II ESA presented in this report, URS concludes that recognized environmental conditions (impacted soil and groundwater) have been confirmed related to oil and gas production and associated brine injection activities at the Burkhart Estate. As a result, these implied soil and/or groundwater releases may be subject to further investigation and/or corrective action(s). 7.0 RECOMMENDATIONS URS recommends that TAMU report the findings of this Phase II ESA to the Site Remediation Section of the Oil and Gas Division of the Railroad Commission (RRC) of Texas in accordance with TAC, Title 16, Part 1, Chapter 3, Rule 3.20, which provides that the RRC be notified of releases from oil and gas production facilities. An option for how to proceed is to apply to the RRC Voluntary Cleanup Program (VCP) as codified in Rule 4.4. The RRC-VCP provides an incentive to remediate oil and gas related pollution by participants as long as they did not cause or contribute to the contamination. Applicants to the program receive a release of liability to the state in exchange for a successful cleanup. Alternately, the RRC may compel cleanup efforts via The Operator Cleanup Program (OCP), which is tasked with oversight of complex pollution cleanups performed by the oil and gas industry. Complex sites include those that occur in sensitive environmental areas as defined by Rule 3.91 and which may require site specific cleanup levels based on risk. Additionally, OCP staff may be involved in the review of data in cases where the source of contamination is uncertain. When cleanup activities are successfully completed by the operator, RRC staff may issue a No Further Action letter acknowledging completion. Texas A&M University Phase II Environmental Site Assessment Burkhart Estate, Matagorda County, Texas 11 May 26, 2011

13 FIGURES

14 P:\GIS_Projects\TAMU_Burkart\GIS\P2ESA\Fig 1 Site Loc.mxd 6:26:40 PM Map Legend Figure 1 Site Location Map Texas A&M University Burkhart Estate Phase II ESA May 26, 2011 Subject Property 0 1,500 3,000

15 P:\GIS_Projects\TAMU_Burkart\GIS\P2ESA\Fig 2 AOIs.mxd 6:28:34 PM M K!(!( J!(!( O Figure 2 Areas of Investigation Map Map Legend Texas A&M University Burkhart Estate Phase II ESA May 26, 2011 T!( R!( S!( P!( Q!( D!( E!( Subject Property!( Select Phase I Observations 0 1,000 2,000 Feet

16 !A WELL-M #* D!P K-01 K-02 #* K-03 #* K-04 #* J-01 #* J-02 #* J-03 #* J-04 #* #* J-05 O-01 #* O-02 P:\GIS_Projects\TAMU_Burkart\GIS\P2ESA\Fig 3 Samps JKM.mxd 6:29:56 PM Map Legend #* D!P!A Figure 3 Sample Locations in Areas J, K, M, and O Texas A&M University Burkhart Estate Phase II ESA May 26, 2011 Subject Property Soil Boring Location Soil Boring and Temporary Groundwater Monitoring Point Location Water Well Location Feet D!P O-03

17 P:\GIS_Projects\TAMU_Burkart\GIS\P2ESA\Fig 4 Samps DEO-T.mxd 6:31:08 PM P-01!A WELL-D!A #* #* WELL-R P-02!A WELL-E S-02 S-01 S-04 #* D!P #* #* S-03 #* S-05 #* D!P Q-01 Q-02 D!P T-01 Figure 4 Sample Locations in Areas D, E, P, Q, R, S, and T Map Legend #* D!P!A Texas A&M University Burkhart Estate Phase II ESA May 26, 2011 Subject Property Soil Boring Location Soil Boring and Temporary Groundwater Monitoring Point Location Water Well Location Feet

18 APPENDIX 1 STATE OF TEXAS WELL REPORTS

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63 APPENDIX 2 SOIL AND GROUNDWATER DATA TABLES

64 Summary of Metals in Soil Arsenic Results in Soil (PCL[TX Background] = 5.9 mg/kg) Barium Results in Soil (PCL[TX Background] = 300 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier Q ' <0.511 Q ' 6.10 Q ' 1.38 Q ' 26.8 S ' 1.42 Q ' 27.3 Q ' 1.52 S ' 32.7 S ' 1.70 S ' 51.2 S ' 2.59 S ' 68.0 K ' 2.67 K ' 118 Q ' 3.00 K ' 120 K ' 3.68 O ' 166 O ' 3.97 O ' 171 O ' 4.67 J ' 228 J ' 5.10 O ' 246 O ' 7.73 Q ' 418 O ' 9.67 O ' 468 Cadmium Results in Soil (PCL[ GW- Soil -Ing ] = 0.75 mg/kg) Chromium Results in Soil (PCL[ GW- Soil -Ing ] = 1200 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier Q ' <0.102 Q ' 2.64 S ' J S ' 5.07 Q ' J S ' 6.94 Q ' J S ' 11.7 Q ' J K ' 12.4 S ' J K ' 13.0 S ' J Q ' 15.4 K ' J Q ' 15.7 K ' J Q ' 16.8 O ' J J ' 18.7 J ' J O ' 20.8 O ' J O ' 22.0 O ' O ' 30.2 O ' O ' 31.9 Lead Results in Soil (PCL[TX Background] = 15 mg/kg) Selenium Results in Soil (PCL[ GW- Soil -Ing ] = 1.1 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier Q ' 1.43 Q ' S ' 3.10 S ' 1.59 S ' 4.18 Q ' 1.75 S ' 6.33 S ' 1.90 K ' 7.19 K ' 2.45 Q ' 7.42 K ' 2.55 Q ' 7.73 O ' 3.95 K ' 8.94 Q ' 4.22 Q ' 11.8 O ' 4.26 O ' 14.8 Q ' 4.31 J ' 16.2 O ' 4.42 O ' 17.7 J ' 4.46 O ' 21.6 S ' 4.53 O ' 22.2 O ' 4.78 Silver Results in Soil (PCL[ GW- Soil -Ing ] = 0.24 mg/kg) Mercury Results in Soil (PCL[TX Background] = 0.04 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier Q ' < S ' < S ' < Q ' < S ' <0.101 S ' < Q ' <0.102 S ' < S ' <0.105 K ' < Q ' <0.107 Q ' < K ' <0.110 Q ' < Q ' <0.111 Q ' < O ' <0.112 K ' < K ' <0.118 O ' J J ' <0.119 J ' J O ' <0.124 O ' J O ' <0.125 O ' J O ' <0.125 O ' Appendix 2 1 of 8

65 Summary of Detected VOCs in Soil Acetone Results in Soil (PCL[ GW- Soil -Ing ] = 21 mg/kg) Benzene Results in Soil (PCL[ GW- Soil -Ing ] = mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier S ' <0.795 K ' < S ' <0.807 K ' < S ' <0.874 S ' < K ' J S ' < K ' S ' J Carbon Disulfide Results in Soil (PCL[ GW- Soil -Ing ] = 6.8 mg/kg) Cyclohexane Results in Soil (PCL[ GW- Soil -Ing ] = 2900 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' < N S ' < K ' < N S ' < S ' <0.265 N S ' < S ' <0.269 N K ' J S ' 1.70 N Ethylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 3.8 mg/kg) Isopropylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 170 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' K ' < K ' S ' S ' 1.24 S ' 1.94 S ' 2.95 S ' 14.0 S ' 9.18 m,p-xylene Results in Soil (PCL[ GW- Soil -Ing ] = 53 mg/kg) Methylcyclohexane Results in Soil (PCL[ GW- Soil -Ing ] = 7800 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' < K ' < K ' < S ' < S ' <0.269 S ' J S ' 1.87 S ' 45.5 S ' 27.0 Naphthalene Results in Soil (PCL[ GW- Soil -Ing ] = 16 mg/kg) n-butylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 61 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' J K ' < K ' S ' 12.2 S ' J S ' 18.3 S ' S ' 35.5 S ' 3.37 n-propylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 22 mg/kg) o-xylene Results in Soil (PCL[ GW- Soil -Ing ] = 35 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' K ' < K ' K ' < S ' 1.53 S ' < S ' 3.36 S ' < S ' 7.49 S ' 20.0 p-isopropyltoluene Results in Soil (PCL[ GW- Soil -Ing ] = 120 mg/kg) tert-butylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 50 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' K ' < K ' S ' < S ' J S ' < S ' S ' 4.53 S ' ,2,4-Trimethylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 4.9 mg/kg) 1,3,5-Trimethylbenzene Results in Soil (PCL[ GW- Soil -Ing ] = 27 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' < K ' < K ' < S ' < S ' < S ' < S ' < S ' 49.1 S ' 23.3 Appendix 2 2 of 8

66 Summary of Detected SVOCs in Soil Benzo[a]pyrene Results in Soil (PCL[ Tot- Soil -Comb ] = 0.56 mg/kg) Dibenzofuran Results in Soil (PCL[ GW- Soil -Ing ] = 17 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' < S ' < K ' < S ' < S ' 1.33 J S ' < S ' 1.56 J K ' S ' 2.52 Fluoranthene Results in Soil (PCL[ GW- Soil -Ing ] = 960 mg/kg) Naphthalene Results in Soil (PCL[ GW- Soil -Ing ] = 16 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' < K ' < S ' < K ' < K ' S ' 11.1 S ' S ' 12.0 S ' S ' 19.5 Phenanthrene Results in Soil (PCL[ GW- Soil -Ing ] = 210 mg/kg) Pyrene Results in Soil (PCL[ GW- Soil -Ing ] = 560 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' K ' < K ' S ' < S ' 1.62 S ' < S ' 1.84 S ' < S ' 2.49 K ' J 2-Methylnaphthalene Results in Soil (PCL[ GW- Soil -Ing ] = 8.5 mg/kg) Sample ID Depth Result (mg/kg) Qualifier K ' K ' 3.56 S ' 23.6 S ' 26.3 S ' 44.2 Appendix 2 3 of 8

67 Summary of TPH in Soil TPH C6-C12 Results in Soil (PCL[ GW- Soil -Ing ] = 33 mg/kg) TPH C12-C28 Results in Soil (PCL[ GW- Soil -Ing ] = 99 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' <7.17 S ' <7.42 S ' <7.42 Q ' <7.55 Q ' <7.55 S ' <7.56 S ' <7.56 K ' <7.86 P ' <7.71 Q ' <7.98 K ' <7.86 Q ' <8.14 Q ' <7.98 J ' <9.21 Q ' <8.14 O ' <9.51 J ' <8.29 K ' <9.79 J ' <8.56 J ' <10.8 J ' <9.21 Q ' <11.4 J ' <9.30 P ' <13.1 O ' <9.51 P ' <13.7 K ' <9.79 S ' <14.6 J ' <10.8 Q ' <15.6 Q ' <11.4 O ' <17.4 P ' <13.1 O ' <18.5 P ' <13.7 K ' 17.2 J S ' <14.6 J ' 24.6 J Q ' <15.6 J ' 24.7 O ' <17.4 O ' 31.6 J O ' <17.8 P ' 36.4 O ' <18.5 J ' 84.3 K ' 52.2 K ' 366 K ' 147 K ' 994 S ' 175 K ' 1460 K ' 248 S ' 1700 K ' 332 K ' 1840 K ' 414 S ' 2150 S ' 428 K ' 2340 S ' 530 S ' 5240 S ' 1390 S ' 6970 S ' 1760 S ' 8220 S ' 2870 S ' TPH C28-C35 Results in Soil (PCL[ GW- Soil -Ing ] = 99 mg/kg) TPH C6-C35 Results in Soil (PCL[ GW- Soil -Ing ] = 33 or 99 mg/kg) Sample ID Depth Result (mg/kg) Qualifier Sample ID Depth Result (mg/kg) Qualifier K ' <7.17 S ' <7.42 S ' <7.42 Q ' <7.55 Q ' <7.55 S ' <7.56 S ' <7.56 K ' <7.86 K ' <7.86 Q ' <7.98 Q ' <7.98 Q ' <8.14 Q ' <8.14 J ' <9.21 J ' <8.56 O ' <9.51 J ' <9.21 K ' <9.79 O ' <9.51 J ' <10.8 K ' <9.79 Q ' <11.4 J ' <10.8 P ' <13.1 Q ' <11.4 P ' <13.7 P ' <13.1 S ' <14.6 P ' <13.7 Q ' <15.6 S ' <14.6 O ' <17.4 Q ' <15.6 O ' <18.5 O ' <17.4 K ' 17.2 J O ' <18.5 J ' 39.3 (C6-C12 < 33) J ' 14.5 J J ' 43.0 (C6-C12 < 33) P ' 17.8 J O ' 50.1 J (C6-C12 < 33) J ' 18.5 J P ' 54.2 (C6-C12 < 33) O ' 18.5 J J ' 84.3 (C6-C12 < 33) K ' 20.6 J K ' 439 K ' 75.1 K ' 1220 K ' 93.8 K ' 1800 K ' 96.7 S ' 2030 S ' 138 K ' 2270 S ' 158 S ' 2820 K ' 159 K ' 2910 S ' 353 J S ' 6260 S ' 452 S ' 8720 S ' 453 S ' S ' 591 S ' Appendix 2 4 of 8

68 Summary of Metals in Groundwater Arsenic Results in Groundwater (PCL[ GW- GW -Ing ] = 0.01 mg/l) Barium Results in Groundwater (PCL[ GW- GW -Ing ] = 2 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-M Well-E-011 < Well-E Well-M J Well-E Cadmium Results in Groundwater (PCL[ GW- GW -Ing ] = mg/l) Chromium Results in Groundwater (PCL[ GW- GW -Ing ] = 0.1 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < Lead Results in Groundwater (PCL[ GW- GW -Ing ] = mg/l) Selenium Results in Groundwater (PCL[ GW- GW -Ing ] = 0.05 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M Well-M-010 < Silver Results in Groundwater (PCL[ GW- GW -Ing ] = 0.12 mg/l) Mercury Results in Groundwater (PCL[ GW- GW -Ing ] = mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < Appendix 2 5 of 8

69 Summary of Detected VOCs in Groundwater Acetone Results in Groundwater (PCL[ GW- GW -Ing ] = 22 mg/l) Benzene Results in Groundwater (PCL[ GW- GW -Ing ] = mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E J Q-02-GW-010 < Q-02-GW J Well-E-010 < Well-M Well-E-011 < O-03-GW Well-M-010 < S-02-GW O-03-GW J Well-E S-02-GW J Ethylbenzene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.7 mg/l) Isopropylbenzene Results in Groundwater (PCL[ GW- GW -Ing ] = 2.4 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier O-03-GW-010 < O-03-GW-010 < Q-02-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW m,p-xylene Results in Groundwater (PCL[ GW- GW -Ing ] = 10 mg/l) Methylcyclohexane Results in Groundwater (PCL[ GW- GW -Ing ] = 120 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier O-03-GW-010 < O-03-GW-010 < Q-02-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW J Naphthalene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.49 mg/l) n-butylbenzene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier O-03-GW-010 < O-03-GW-010 < Q-02-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW n-propylbenzene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) o-xylene Results in Groundwater (PCL[ GW- GW -Ing ] = 10 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier O-03-GW-010 < O-03-GW-010 < Q-02-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW p-isopropyltoluene Results in Groundwater (PCL[ GW- GW -Ing ] = 2.4 mg/l) tert-butylbenzene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier O-03-GW-010 < O-03-GW-010 < Q-02-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW Toluene Results in Groundwater (PCL [ GW- GW -Ing ] = 1 mg/l) 1,2,4-Trimethylbenzene Results in Groundwater (PCL [ GW- GW -Ing ] = 0.24 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier O-03-GW-010 < O-03-GW-010 < Q-02-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW J S-02-GW ,3,5-Trimethylbenzene Results in Groundwater (PCL [ GW- GW -Ing ] = 1.2 mg/l) Sample ID Result (mg/l) Qualifier O-03-GW-010 < Q-02-GW-010 < Well-E-010 < Well-E-011 < Well-M-010 < S-02-GW Appendix 2 6 of 8

70 Summary of Detected SVOCs in Groundwater Bis(2-ethylhexyl)phthalate Results in Groundwater (PCL [ GW- GW -Ing ] = mg/l) Dibenzofuran Results in Groundwater (PCL [ GW- GW -Ing ] = mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < S-02-GW Well-M-010 < Well-M S-02-GW Fluorene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) Naphthalene Results in Groundwater (PCL[ GW- GW -Ing ] = 0.49 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW Phenanthrene Results in Groundwater (PCL [ GW- GW -Ing ] = 0.73 mg/l) 2-Methylnaphthalene Results in Groundwater (PCL [ GW- GW -Ing ] = mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier Well-E-010 < Well-E-010 < Well-E-011 < Well-E-011 < Well-M-010 < Well-M-010 < S-02-GW S-02-GW Appendix 2 7 of 8

71 Summary of TPH in Groundwater TPH C6-C12 Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) TPH C12-C28 Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier T-01-GW-013 <0.670 T-01-GW-013 <0.670 Well-E-011 <0.681 Well-E-011 <0.681 Well-M-010 <0.682 Well-M-010 <0.682 WellWM-D-010 <0.686 WellWM-D-010 <0.686 Well-R-010 <0.703 Well-R-010 <0.703 Well-E-010 <0.704 Well-E-010 <0.704 S-02-GW S-02-GW TPH C28-C35 Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) TPH C6-C35 Results in Groundwater (PCL[ GW- GW -Ing ] = 0.98 mg/l) Sample ID Result (mg/l) Qualifier Sample ID Result (mg/l) Qualifier S-02-GW-010 <0.659 T-01-GW-013 <0.670 T-01-GW-013 <0.670 Well-E-011 <0.681 Well-E-011 <0.681 Well-M-010 <0.682 Well-M-010 <0.682 WellWM-D-010 <0.686 WellWM-D-010 <0.686 Well-R-010 <0.703 Well-R-010 <0.703 Well-E-010 <0.704 Well-E-010 <0.704 S-02-GW Appendix 2 8 of 8

72 APPENDIX 3 LABORATORY ANALYTICAL REPORT

73 April 28, 2011 Bob Schaefer URS Corporation 9400 Amberglen Bldg E Austin, Texas TEL: (512) FAX: (512) Order No: RE: Burkhart Matagorda Co. Dear Bob Schaefer: DHL Analytical received 45 sample(s) on 4/15/2011 for the analyses presented in the following report. There were no problems with the analyses and all data met requirements of NELAC except where noted in the Case Narrative. All non-nelac methods will be identified accordingly in the case narrative and all estimated uncertainties of test results are within method or EPA specifications. If you have any questions regarding these tests results, please feel free to call. Thank you for using DHL Analytical. Sincerely, John DuPont General Manager This report was performed under the accreditation of the State of Texas Laboratory Certification Number: T Double Creek Dr. Round Rock, TX Phone: (512) Fax: (512) Page 1 of 226

74 Table of Contents Miscellaneous Documents... 3 Case Narrative Sample Summary Prep Dates Report Analytical Dates Report Sample Results Analytical QC Summary Report MQL Summary Report Page 2 of 226

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