PHASE II ENVIRONMENTAL SITE ASSESSMENT HOWARD UNIVERSITY EAST CAMPUS (DIVINITY SCHOOL) 1400 SHEPHERD STREET, NE WASHINGTON, DC

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1 PHASE II ENVIRONMENTAL SITE ASSESSMENT HOWARD UNIVERSITY EAST CAMPUS (DIVINITY SCHOOL) 1400 SHEPHERD STREET, NE WASHINGTON, DC ECS PROJECT NO. 47:6230-A FOR ZOM MID-ATLANTIC, INC AUGUST 24, 2018

2 August 24, 2018 Mr. Christopher Love ZOM Mid-Atlantic, Inc st Street, NW Washington, DC ECS Project No. 47:6230-A Reference: Phase II Environmental Site Assessment Report, Howard University East Campus (Divinity School), 1400 Shepherd Street, NE, Washington, DC Dear Mr. Love: ECS Mid-Atlantic, LLC (ECS) is pleased to present the following Phase II Environmental Site Assessment (ESA) report for the above-referenced site in Washington, DC. PROJECT BACKGROUND The property consists of an approximately acre parcel of land improved with the Howard University Divinity School including the Divinity Library, a vacant four-story historic building consisting of a library, offices, dormitories, a kitchen and cafeteria, a chapel, and a central courtyard. Additional improvements at the subject property include a two-story single family residence and a maintenance shed. Based on provided information, the property is being considered for redevelopment. ECS completed a Phase I ESA of the subject property in July 2018 (ECS Project Number 47:6230, dated July 2, 2018). The Phase I ESA identified the following Recognized Environmental Conditions (RECs) for the subject property: The subject property was identified on the DC underground storage tank (UST) database as "HU - School of Divinity" addressed 1400 Shepherd Street, NE 14th & Shepherd Street, NE. The subject property was listed with three "Permanently Out of Use" USTs including one 1,000-gallon gasoline, one 4,000-gallon heating oil, and one 2,000-gallon heating oil UST. Additionally, one 550-gallon diesel UST with a "Currently In Use" status was listed at the subject property. ECS reviewed the DC Property Information Verification System (PIVS) for building department records. The PIVS included three construction/miscellaneous permits including permits for the removal of two 4,000-gallon underground storage tanks. The tank removal permit was dated March 7, 2005; however, no additional information related to the tank removal was available for review. Further, the Veeder Root tank monitoring system located in a mechanical room of the Divinity Library building did not appear to be operating during the site reconnaissance. Based on the potential for a petroleum release, the UST listing was considered a REC for the subject property.

3 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 2 Staining was observed on the dirt floor of the maintenance shed located on the central-eastern portion of the subject property. The staining was suspected to be related to vehicle and/or equipment repairs conducted in the maintenance shed. Containers of mechanical oils and degreasers were observed in the maintenance shed. The stained soil and suspected use of the maintenance shed for vehicle or equipment repairs was considered a recognized environmental condition (REC) for the subject property. Additionally, the following Historical Recognized Environmental Condition (HREC) was identified: The subject property was listed on the DC Leaking Underground Storage Tank (LUST) database as "Dr. Lynn Hamerling" addressed 1421 Taylor Street, NE. The subject property was listed with one closed LUST case which was opened in 1999 related to reports of heating oil in the sub-surface soil. The closed on-site LUST case was considered a HREC for the property. The objective of this investigation was to collect soil and groundwater samples to assess whether the subsurface had been adversely impacted by previous on-site activities. Utility Clearance SCOPE OF WORK ECS contracted a private utility locator to identify and mark the underground utilities in the work area (see boring location diagram included as Appendix I) on the property. The utilities were located on August 7, The proposed location of boring B-6 (according to the work plan) was not accessible due to dense vegetation. Therefore, boring B-6 was moved to the north in a more accessible area. Soil Borings On August 8, 2018, ECS employed a track-mounted Geoprobe to advance a total of six (6) soil borings across the site. The soil borings were drilled to depths ranging from approximately 17 to 27 feet below ground surface (bgs), at which point Geoprobe refusal was encountered. The Geoprobe used a hydraulic hammer to push a 2.5 diameter steel rod with a clear PVC sleeve into the ground in five-foot increments. The macrocore was then withdrawn from the ground and the sleeve removed, containing a relatively undisturbed soil core. The sleeve was cut open allowing examination of the entire soil core, and sampling of soil from the core. Soil was screened in 5-foot intervals throughout the depth of each boring. The soil was screened in the field with a Photoionization Detector (PID), which measures total volatile organic compounds (VOCs) emanating from the soil. While drilling the soil boring B-6, white to light gray sandy clay was encountered at a depth of 15 to 20 feet bgs, which was

4 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 3 saturated with free liquid petroleum product. Petroleum odors were noted in some of the other borings. However, free liquid petroleum product was only observed in the boring B-6. Temporary PVC wells were installed in borings B-5, B-6 and B-2 in order to collect groundwater samples. The wells consisted of ten feet of machine-slotted well screen topped with a solid PVC riser pipe to the surface. Soil Sampling SAMPLING METHODOLOGY Based on field screening results, three soil samples from each boring were selected for laboratory analysis. During drilling activities, the PID malfunctioned and was not able to detect VOCs in the soil. Therefore, the soil samples were selected on the basis of visual and olfactory observations, such as staining and petroleum odors. When no evidence of petroleum impact was apparent in the soil cores, the soil samples were collected from (1) the top five feet of the borings, (2) immediately above the water table, and (3) the base of the boring. All selected soil samples were placed in laboratory grade glassware, packed on ice and submitted under chain-of-custody protocol to an independent laboratory for analysis of total petroleum hydrocarbons diesel-range and gasoline-range organics (TPH-DRO and TPH-GRO), polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), and Resource Conservation and Recovery Act (RCRA) metals. Groundwater Sampling Saturated soil conditions indicative of groundwater were encountered in each of the six borings prior to termination of the borings at depths ranging from 10 feet to 15 feet bgs. ECS collected groundwater samples from three of the six borings (B-2, B-5 and B-6). The groundwater samples were collected with a peristaltic pump with dedicated tubing. The groundwater samples were placed into laboratory-grade bottles with appropriate preservative, packed on ice and submitted to an independent laboratory for analysis of TPH- DRO, TPH-GRO, PAHs, and VOCs. Temporary wells were removed after sampling. The borings were filled with bentonite clay according to the District Department of Energy and Environment (DOEE) guidelines. RESULTS A total of six borings were advanced across the property. Obvious evidence of impact (i.e. PID readings, odors, staining, etc.) was observed in three of the six soil borings and free liquid petroleum product was observed in boring B-6. Detected soil contaminant concentrations were compared to the DC Risk Based Corrective Action (RBCA) Technical Guidance Tier 1, Table 5-9 Risk-Based Screening Levels (RBSLs) for a Resident Adult, in Sub-Surface Soil, for Indoor Inhalation. Additionally, detected concentrations of TPH GRO, TPH DRO, benzene, ethylbenzene, toluene, and xylenes were compared to the DC RBCA

5 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 4 Tier 0 screening level. Where the DC RBSLs were not established for certain compounds, the detected concentrations were compared with their respective EPA Regional Screening Level (RSL) for Resident Soil. The groundwater contaminant concentrations were compared to the DC RBCA Technical Guidance Tier 1, Table 5-9 Risk-Based Screening Levels (RBSLs) for a Resident Adult, in Groundwater, for Indoor Inhalation. Where the DC RBSLs were not established for certain compounds, the detected concentrations were compared with their respective EPA RSL for Maximum Contaminant Level (MCL). If the MCL was not established for certain compounds, the detected concentrations were compared with their respective EPA RSL for tapwater. The results are summarized below. The boring logs are included as Appendix II. The laboratory results are summarized in tables provided in Appendix III. A full laboratory report is provided in Appendix IV. Soil Sampling s VOCs Thirteen VOCs were detected in one or more of the eighteen analyzed soil samples. Three samples had detectable concentrations above the Tier 1 screening levels. Most of the VOCs detected are typically associated with petroleum products. Benzene was detected in three of the eighteen analyzed soil samples. In borings B-1 and B- 6, the detected benzene concentrations were 2.8 micrograms per kilogram (µg/kg) and 2.3 µg/kg, respectively. These concentrations were below the respective DC Tier 0 screening level of 5 µg/kg. Benzene was detected at a concentration of 7.2 ug/kg in boring B-5 at the depth of 27 feet bgs and exceeded its respective DC Tier 0 screening level. The benzene concentration in B-5 also exceeded the DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 5.06 µg/kg. n-butylbenzene was detected at an estimated concentration of 4 µg/kg in boring B-6 at a depth of 5 feet bgs, and at a concentration of 17,600 µg/kg in B-6 at a depth of 20 feet bgs. The concentrations of n-butylbenzene were below the EPA RSL for resident soil of 3,900,000 ug/kg. sec-butylbenzene was detected at a concentration of 3,860 µg/kg in boring B-6 at a depth of 20 feet bgs, which was below its EPA RSL for resident soil of 7,800,000 µg/kg. Carbon disulfide was detected in boring B-6 at the depth of 10 feet bgs, at an estimated concentration of 2.6 µg/kg, which was below its EPA RSL for resident soil of 770,000 µg/kg. Ethylbenzene was detected in eight of the eighteen soil samples at concentrations ranging from 3 µg/kg to 27,300 µg/kg. In boring B-6, the detected concentrations of ethylbenzene were 118 µg/kg at 5 feet bgs and 27,300 µg/kg at 20 feet bgs, which both exceeded the DC

6 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 5 Tier 0 screening level of 40 µg/kg and the DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 40.8 µg/kg. Isopropylbenzene (Cumene) was detected in two of the eighteen soil samples at concentrations of 3.4 µg/kg in boring B-5 at a depth of 5 feet bgs and 6,960 µg/kg in boring B-6 at a depth of 20 feet bgs. The concentrations of isopropylbenzene did not exceed the EPA RSL for resident soil of 1,900,000 ug/kg. 4-Isopropyltoluene was detected at a concentration of 7,760 µg/kg in boring B-6 at the depth of 20 feet bgs. There is no established screening level for isopropyltoluene. Naphthalene was detected in six of the eighteen analyzed soil samples at concentrations ranging from 3.6 µg/kg to 31,200 µg/kg. The concentration of 31,200 µg/kg detected in boring B-6 at 20 feet bgs exceeded its DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 188 µg/kg. The remaining detected concentrations of naphthalene were below the DC Tier 1 screening level. n-propylbenzene was detected in four of the eighteen analyzed soil samples at concentrations ranging from 3.7 µg/kg to 26,500 µg/kg. The concentrations of n- propylbenzene did not exceed its EPA RSL for resident soil of 3,800,000 ug/kg. Toluene was detected in fourteen of the eighteen analyzed soil samples at concentrations ranging from 2.6 µg/kg to 14,300 µg/kg. The concentration of 14,300 µg/kg detected in boring B-6 at 20 feet bgs exceeded its DC Tier 0 screening level of 9,600 ug/kg and DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 10,000 µg/kg. The remaining detected concentrations of toluene were below the DC Tier 0 screening level. 1,2,4-Trimethylbenzene was detected in ten of the eighteen analyzed soil samples at concentrations ranging from 2.5 µg/kg to 175,000 µg/kg. The concentrations of 1,2,4- trimethylbenzene did not exceed the EPA RSL for resident soil of 300,000 ug/kg. 1,3,5-Trimethylbenzene was detected in five of the eighteen analyzed soil samples at concentrations ranging from 9.5 µg/kg to 50,300 µg/kg. The concentrations of 1,3,5- trimethylbenzene did not exceed the EPA RSL for resident soil of 270,000 µg/kg. Xylenes (total) were detected in fourteen of the eighteen analyzed soil samples at concentrations ranging from 3.2 µg/kg to 173,800 µg/kg. The concentration of 173,800 µg/kg detected in boring B-6 at 20 feet bgs exceeded its DC Tier 0 screening level and DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 3,860 µg/kg. The remaining detected concentrations of xylenes were below the DC Tier 0 screening level. PAHs PAHs were detected in three of the eighteen analyzed soil samples from borings B-2, B-5, and B-6.

7 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 6 Benzo[b]fluoranthene was detected in one of the analyzed soil samples at a concentration of 516 µg/kg in B-6 at a depth of 5 feet bgs. The detected concentration of benzo[b]fluoranthene was below the DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 3,460,000 ug/kg. 2-Methylnaphthalene was detected in one of the analyzed soil samples at a concentration of 9,690 µg/kg in B-6 at a depth of 20 feet bgs. The detected concentration was below its EPA RSL for resident soil of 240,000 µg/kg. Naphthalene was detected in one of the analyzed soil samples at a concentration of 8,650 µg/kg in B-6 to a depth of 20 feet bgs. The detected naphthalene concentration exceeded its DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 188 ug/kg. Pyrene was detected in one of the analyzed soil samples at a concentration of 491 µg/kg in B-6 at 5 feet bgs. The detected concentration was below its EPA RSL for resident soil of 1,800,000 µg/kg. TPH DRO and TPH GRO Detectable concentrations of TPH-DRO and TPH-GRO were identified in seven of the eighteen analyzed soil samples. TPH-DRO was detected in boring B-5 at a depth of 23 feet bgs at a concentration of 85 milligrams per kilogram (mg/kg), and in boring B-6 at a depth of 5 feet bgs at a concentration of 95.8 mg/kg and at a depth of 20 feet bgs at 106 mg/kg. The detected TPH-DRO concentration of 106 mg/kg exceeded the DC Tier 0 screening level of 100 mg/kg. However, the detected TPH-DRO concentration was below the DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 2,120 mg/kg. TPH-GRO was detected in seven of the eighteen soil samples at concentrations ranging from 0.29 mg/kg to 819 mg/kg. The highest concentration of TPH-GRO (819 mg/kg) was detected in boring B-6 at the depth of 20 feet bgs, and exceeded the DC Tier 0 screening level of 100 mg/kg and DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult of 54.4 mg/kg. RCRA Metals Five metals were detected in one or more of the eighteen analyzed soil samples. Arsenic was detected in two of the eighteen samples at a concentration of 289 mg/kg in B-1 at a depth of 5 feet bgs and 19.7 mg/kg in B-4 at a depth of 10 feet bgs. Both concentrations exceeded the EPA RSL for resident soil of 0.68 mg/kg. Barium was detected in twelve of the eighteen samples at concentrations ranging from 7.66 mg/kg to 329 mg/kg. None of the concentrations exceeded the EPA RSL for resident soil of 15,000 mg/kg. Total Chromium was detected in twelve of the eighteen samples at concentrations ranging from 7.54 mg/kg to mg/kg. There is no established screening level for total chromium.

8 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 7 Lead was detected in seventeen of the eighteen samples at concentrations ranging from 2.69 mg/kg to 109 mg/kg. None of the concentrations exceeded the EPA RSL for resident soil of 400 mg/kg. Mercury was detected in seven of the eighteen samples at concentrations ranging from 0.08 mg/kg to 1.01 mg/kg. None of the concentrations exceeded the EPA RSL for resident soil of 11 mg/kg. Groundwater Sampling s Groundwater samples were collected from boring B-2, B-5, and B-6. All three groundwater samples collected had detected concentrations of VOCs. VOCs A total of twelve VOCs were detected. The compounds which exceeded their respective screening levels are discussed below. tert-amyl Alcohol (TAA) was detected at a concentration of 270 micrograms per liter (µg/l) in B-5 which exceeded the EPA RSL of 6.3 µg/l for tapwater. Benzene was detected at a concentration of 9.8 µg/l in B-2, 1,400 µg/l in B-5, and 927 µg/l in B-6, each of which exceeded the DC Tier 0 screening level of 5 ug/l. Additionally, the concentrations detected in B-5 and B-6 exceeded the DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 67.6 µg/l. Ethylbenzene was detected a concentration of 44.9 µg/l in B-2, 104 µg/l in B-5, and 3,540 µg/l in B-6. The detected concentrations in B-5 and B-6 exceeded the DC Tier 0 screening level of 70 ug/l. Additionally, the ethylbenzene concentration in B-6 exceeded the DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 206 µg/l. Naphthalene was detected at a concentration of 12.7 µg/l in B-2 and 614 µg/l in B-6. The detected naphthalene concentration in B-6 exceeded the DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 191 µg/l. Toluene was detected at a concentration of 188 µg/l in B-2, 1,580 µg/l in B-5, and 11,600 µg/l in B-6, each of which exceeded the DC Tier 0 screening level of 100 ug/l. However, none of the toluene concentrations exceeded the DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 90,000 µg/l. 1,2,4-Trimethylbenzene was detected at a concentration of 19.0 µg/l in B-2, 1,200 µg/l in B-5 and 2,770 µg/l in B-6. The detected concentrations in B-5 and B-6 exceeded its EPA RSL of 56 µg/l for tapwater.

9 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 8 1,3,5-Trimethylbenzene was detected at a concentration of 4.5 µg/l in B-2, 585 µg/l in B-5 and 716 µg/l in B-6. The detected concentrations in B-5 and B-6 exceeded its EPA RSL of 60 ug/l for tapwater. PAHs 2-Methylnaphthalene was detected at a concentration of 8.52 µg/l in B-2, 100 µg/l in B-5 and 464 µg/l in B-6. The detected concentrations in B-5 and B-6 exceeded its EPA RSL of 36 ug/l for tapwater. Naphthalene was detected at a concentration of 22.7 µg/l in B-2, 6.05 µg/l in B-5 and 880 ug/l in B-6. The detected concentration B-6 exceeded its DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 191 µg/l. TPH DRO and TPH GRO TPH-DRO was detected in the groundwater samples from B-5 and B-6 at concentrations of 7.04 milligrams per liter (mg/l) and 87.7 mg/l, respectively. The TPH-DRO concentrations were below the DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 245 mg/l. TPH-GRO was detected in each of the three groundwater samples at a concentration of 1.35 mg/l in B-2, 39.8 mg/l in B-5 and 52.0 mg/l in B-6. The detected concentrations in B-5 and B-6 exceeded the DC Tier 1 RBSL for groundwater to indoor inhalation for a resident adult of 38.8 mg/l. SUMMARY AND CONCLUSIONS In order to assess subsurface environmental conditions at the site, ECS advanced six borings across the site with a track-mounted Geoprobe to depths ranging between 17 to 27 feet bgs at which point refusal was encountered. Saturated conditions were observed in each of the six borings at depths ranging from 10 to 15 feet bgs. Three groundwater samples were collected from temporary wells. While drilling the soil boring B-6, white to light gray sandy clay was encountered and was saturated with free liquid petroleum product between a depth of 15 and 20 feet bgs. Petroleum odors were noted in some of the other borings. However, free liquid petroleum product was only observed in boring B-6. A total of 18 soil samples were submitted to an independent laboratory for analysis of TPH DRO, TPH GRO, VOCs, PAHs, and RCRA 8 Metals. Concentrations of VOCs including benzene, ethylbenzene, toluene, xylenes, and/or naphthalene exceeded their respective screening levels in three of the six samples collected from borings B-5 and B-6. Detected concentrations of PAHs were below their respective DC RBSLs or EPA RSLs; except for naphthalene which exceeded its DC Tier 1 RBSL for subsurface soil to indoor inhalation for a resident adult in the sample from boring B-6 collected at 20 feet bgs. TPH-DRO and TPH-GRO were detected in one of the soil samples exceeding its DC Tier 0 screening level and/or DC Tier 1 RBSL for subsurface soil to indoor

10 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 9 inhalation for a resident adult. None of the metals detected exceeded their respective EPA RSL for a resident adult, with the exception of arsenic. Both detected arsenic concentrations exceeded the EPA RSL for resident soil and were above typical background concentrations for this geologic area. In the event that petroleum-impacted material is excavated, it will need to be disposed of appropriately at a landfill or treatment/disposal facility permitted to accept such wastes. Disposal criteria for contaminated soil will depend on the jurisdiction in which it is to be disposed. In the District of Columbia, soils may be re-used on site if TPH-DRO and TPH- GRO concentrations are no greater than their applicable Tier 0 and/or Tier 1 screening levels, and individual constituent concentrations of BTEX are no greater than: part per million (ppm) for benzene; 9.6 ppm for toluene; 0.04 ppm for ethylbenzene; and, 3.86 ppm for total xylenes. Soils that are excavated containing petroleum concentrations above these thresholds or below these thresholds that cannot be reused onsite, cannot be disposed of within the District limits and must be disposed of at an appropriate disposal or treatment facility. In Maryland, based on the Land Materials Administration Fact Sheet dated August 2017, soil containing petroleum (TPH DRO or TPH GRO) concentrations less than 230 mg/kg may be used as Category 1 fill materials at both residential and non-residential sites. Soil containing petroleum (TPH DRO or TPH GRO) concentrations less than 620 mg/kg may be used as Category 2 fill materials on non-residential sites only. Soils containing petroleum concentrations greater than 620 mg/kg will need to be disposed at a licensed disposal/treatment facility capable of accepting the material. However, each of the other detected contaminants will also need to be below their respective residential or commercial screening level for use as Category 1 or 2 fill material. In Virginia, solid waste management regulations divide petroleum-impacted soils into various classes depending on concentration. Soils containing petroleum concentrations less than 50 mg/kg and total BTEX less than 10 mg/kg may be disposed with certain restrictions (see 9VAC D.2.d). Soils containing less than 500 mg/kg petroleum may be disposed of in a lined landfill permitted to receive such wastes. Soils containing petroleum concentrations greater than 500 mg/kg may not be disposed of in Virginia landfills, unless the permit expressly allows for such disposal. In practice, it is often difficult for developers and contractors to find a suitable disposal location for the marginally-impacted petroleum contaminated soils- i.e. soils containing detectable petroleum concentrations below the regulatory thresholds. This is due to the paucity of net fill construction sites in the area, and the relative abundance of legitimately clean fill materials with no petroleum contamination. Given the option, the developers of most fill sites will prefer clean fill materials over marginally-impacted materials. Consequently, it is common practice in this region to dispose of even low-level contaminated soils at petroleum-impacted soil facilities such as Clean Earth, Inc. of Greater Washington (Upper Marlboro, Maryland) or Soil Safe, Inc. (Brandywine, Maryland).

11 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 10 Detected groundwater concentrations of VOCs including benzene, ethylbenzene, naphthalene, toluene, xylenes, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene and TAA, PAHs including 2-methylnaphthalene and naphthalene, TPH-DRO, and TPH-GRO exceeded their respective DC RBSLs or EPA RSLs. The property and surrounding areas are supplied with public water. Therefore, the primary risk pathway for exposure is from volatilization of subsurface contamination to indoor air. In the event contamination exceeding risk-based thresholds is left in place, ECS recommends that a vapor barrier be constructed beneath future buildings constructed. If the existing building will remain, ECS recommends soil vapor sampling to determine if the subsurface contamination poses an unacceptable vapor risk for the current building. If future redevelopment will result in groundwater dewatering during construction activities, A National Pollutant Discharge Elimination System (NPDES) permit from EPA and approval from DOEE will need to be obtained prior to discharge of the groundwater to the municipal separate storm sewer system (MS4). Additional groundwater characterization would be necessary in order to obtain DOEE approval to discharge. Based on the sampling results, it is possible that treatment of the groundwater would be necessary prior to discharge to the MS4. Based on the soil and groundwater analytical results, it is ECS s opinion that the detected contaminant concentrations in soil and groundwater could pose an unacceptable risk to the environment and human health. The presence of free petroleum product in boring B-6 is a condition that ECS is obligated to report to the DOEE, as are the exceedances of the Tier 0 and Tier 1 Screening Levels identified for certain soil and groundwater samples. DOEE will likely open a Leaking Underground Storage Tank (LUST) case for the property as a result of the findings. Based on our experience with similar projects in the District of Columbia, additional investigation and remediation will be required before the case will be closed. While we do not know exactly what DOEE will require, it is ECS s opinion that the additional work required for the site will include the installation of additional soil borings to assess the horizontal extent of the soil contamination, the removal of USTs and contaminated soil in the area of SB-5 and SB-6 (the maintenance shed area as discussed in the Phase I ESA), and the installation of down-gradient monitoring wells to assess the potential for off-site migration of contaminants. Additional remedial activities may be required by DOEE. QUALIFICATIONS The conclusions presented within this report are based upon a reasonable level of investigation within normal bounds and standards of professional practice for a site in this particular geographic and geologic setting, and the areas of the site accessible for drilling. The results of this study are limited to the specific areas and elevations tested. Boring locations were chosen based on accessible areas of the site, located to avoid surface and subsurface obstructions.

12 ZOM Mid-Atlantic, Inc. ECS Project No. 47:6230-A August 24, 2018 Page 11 The findings of this study are not intended to serve as an audit of health and safety or compliance issues pertaining to improvements or occupant activities on-site. All observations, conclusions, and recommendations pertaining to environmental conditions at the subject site are limited to conditions observed, and or materials reviewed at the time this study was undertaken. No other warranty, expressed or implied, is made with regard to the conclusions and recommendations presented within this report. This report is provided for the exclusive use of ZOM Mid-Atlantic, Inc., and their prospective partners. This report is not intended to be used or relied upon in connection with other projects or by other unidentified third parties. The use of this letter by any undesignated third party or parties would be at such party's sole risk and ECS disclaims liability for any such third party use or reliance. ECS has not completed or used any form of predetermined language to report the conclusions of this work and it is our understanding that we will not be required to do so. Compensation for this investigation is not contingent upon results, and ECS has conducted this Phase II ESA objectively without reference to any particular outcome desired by the client. If you have any questions about this report or other aspects of this project, please contact us at (703) Respectfully submitted, ECS MID-ATLANTIC, LLC Swardhuni Pethe Environmental Scientist Pamela Furst, LEED AP Environmental Senior Project Manager David J. Bookbinder, C.P.G. Environmental Senior Project Manager Appendix I Appendix II Appendix III Appendix IV Boring Location Diagram Boring Logs Summary of Final Laboratory s I:\_e-projects\ \6230- A HU East Campus Phase II ESA\Report\6230-A_Phase II Report_FINAL.docx

13 APPENDIX I BORING LOCATION DIAGRAM

14 B 1 B 2 B 3 B 4 B 5 B 6 Boring Loca on Boring Location Diagram Howard University East Campus 1400 Shepherd Street NE Washington, DC ECS Project No.: 47:6230 A Scale: Not to Scale Date: 8/15/2018

15 APPENDIX II BORING LOGS

16 This information pertains only to this boring and should not be in terpreted as being indicative of the site. PROJECT: MONITORING WELL NO. B-1 CLIENT: PROJECT NO. LOCATION: DRILLER: DRILL RIG: Elevation/ Depth (Ft) PID Reading Sample Number Sample Recovery (in/in) HU East Campus Blow Count JETCO Inc. GeoProbe Graphic Log Soil Classification Topsoil GC-SC Fill CL-ML SW/SP SM/MH 3" topsoil Sandy Clay with 2" stone (GC-SC Fill), brown Silty Clay (CL-ML), brown, med fine, moist Sand (SW/SP), brown, loose, moist Silty Sand (SM/MH), orange-brown, loose, wet Refusal at 17' ELEVATION: N/A DATE DRILLED: 8/9/2018 DEPTH TO WATER: SOIL DESCRIPTION 12 LOGGED BY: MMH, SP Page 1 of 1

17 This information pertains only to this boring and should not be in terpreted as being indicative of the site. PROJECT: MONITORING WELL NO. B-2 CLIENT: PROJECT NO. LOCATION: DRILLER: DRILL RIG: Elevation/ Depth (Ft) PID Reading Sample Number Sample Recovery (in/in) HU East Campus Blow Count JETCO Inc. GeoProbe Graphic Log Soil Classification Topsoil SM/MH 2" topsoil Silty Sand (SM/MH), orange-brown, loose, moist loose, dry color change to light brown color change to light brown/gray, moist Refusal at 16' ELEVATION: N/A DATE DRILLED: 8/9/2018 DEPTH TO WATER: SOIL DESCRIPTION 15 LOGGED BY: MMH, SP Page 1 of 1

18 This information pertains only to this boring and should not be in terpreted as being indicative of the site. PROJECT: MONITORING WELL NO. B-3 CLIENT: PROJECT NO. LOCATION: DRILLER: DRILL RIG: Elevation/ Depth (Ft) PID Reading Sample Number Sample Recovery (in/in) HU East Campus Blow Count JETCO Inc. GeoProbe Graphic Log Soil Classification Topsoil CH-MH MH/SM MH CH 3" topsoil Silty Clay (CH-MH), brown, soft Silty sand (MH/SM), brown to red, soft, loose silty sand (MH/SM), red, coarse, loose, slightly moist silty sand (MH/SM), orange/brown, coarse, loose, wet silt (MH), red, med fine, moist color change to orange/brown clay (CH), brown muttling, med firm, refusal at 23' ELEVATION: N/A DATE DRILLED: 8/9/2018 DEPTH TO WATER: SOIL DESCRIPTION 15 LOGGED BY: MMH, SP Page 1 of 1

19 This information pertains only to this boring and should not be in terpreted as being indicative of the site. PROJECT: MONITORING WELL NO. B-4 CLIENT: PROJECT NO. LOCATION: DRILLER: DRILL RIG: Elevation/ Depth (Ft) PID Reading Sample Number Sample Recovery (in/in) HU East Campus Blow Count JETCO Inc. GeoProbe Graphic Log Soil Classification Topsoil CH-MH MH/SM MH/CH CH/SC 2" roots and grass clayey silt (CH-MH), brown, med coarse, med loose, moist Silty sand (MH/SM), orange brown, coarse, moist wet Silty clay (MH/CH), white, trace sand, moist Clayey Sand (CH/SC), white, med coarse, med loose, odor refusal at 23' ELEVATION: N/A DATE DRILLED: 8/9/2018 DEPTH TO WATER: SOIL DESCRIPTION 15 LOGGED BY: MMH, SP Page 1 of 1

20 This information pertains only to this boring and should not be in terpreted as being indicative of the site. PROJECT: MONITORING WELL NO. B-5 CLIENT: PROJECT NO. LOCATION: DRILLER: DRILL RIG: Elevation/ Depth (Ft) PID Reading Sample Number Sample Recovery (in/in) HU East Campus Blow Count JETCO Inc. GeoProbe Graphic Log Soil Classification Gravel GP-SP Fill MH/SM ML/SM ML-CL ML/SM CH 6" gravel Sandy Fill and Gravel (GP-SP Fill), brown, coarse, loose Sandy Silt (MH/SM), brown, soft, moist silty sand, orange/brown, coarse, wet, Sulfur odor Silty Clay (ML-CL), white, coarse, wet Silty sand (ML/SM), white/gray, coarse, med loose, moist color change to gray refusal at 23' Clay (CH), brown/red, firm, fine, dense refusal at 27' ELEVATION: N/A DATE DRILLED: 8/9/2018 DEPTH TO WATER: SOIL DESCRIPTION 10 LOGGED BY: MMH, SP Page 1 of 1

21 This information pertains only to this boring and should not be in terpreted as being indicative of the site. PROJECT: MONITORING WELL NO. B-6 CLIENT: PROJECT NO. LOCATION: DRILLER: DRILL RIG: Elevation/ Depth (Ft) PID Reading Sample Number Sample Recovery (in/in) HU East Campus Blow Count JETCO Inc. GeoProbe Graphic Log Soil Classification Asphalt GM Fill SW/SP SP-SC 4" asphalt silty gravel (GM Fill), brown Sand (SW/SP), brown, coarse, loose, moist black staining, odor odor continues Sandy Clay (SP-SC), white/light gray, odor, and free product Refusal at 20' ELEVATION: N/A DATE DRILLED: 8/9/2018 DEPTH TO WATER: SOIL DESCRIPTION 10 LOGGED BY: MMH, SP Page 1 of 1

22 APPENDIX III SUMMARY OF ANALYTICAL RESULTS

23 Table 1 Summary of Soil VOCs s 1400 Shepherd Street NE Washington, DC Sample ID B1-5 B1-15 B1-17 B2-5 B2-15 B2-17 B3-5 B3-15 B3-23 B4-5 B4-10 B4-23 B5-5 B5-15 B5-27 B6-5 B6-10 B6-20 Sample Date 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 Screening Level VOCs ug/kg * ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Ethylbenzene nd nd nd nd nd 5.3 nd nd nd nd nd Toluene 9, nd nd nd nd Xylenes (total) 3, nd nd nd nd Benzene 5 0 nd 2.8 nd nd nd nd nd nd nd nd nd nd nd nd nd nd Naphthalene nd nd nd nd nd nd 6.5 nd nd nd nd nd nd n-propylbenzene 3,800,000 2 nd nd nd nd nd nd 3.7 nd nd nd nd nd nd nd nd ,2,4-Trimethylbenzene 300, nd nd nd nd nd 46.7 nd 2.5 nd nd ,3,5-Trimethylbenzene 270,000 2 nd nd nd nd nd nd 10.6 nd nd nd nd nd 21.2 nd nd Isopropylbenzene (Cumene) 1,900,000 2 nd nd nd nd nd nd nd nd nd nd nd nd 3.4 nd nd 8.6 nd n-butylbenzene 3,900,000 2 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 4.0 nd Carbon disulfide 770,000 2 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 2.6 nd sec-butylbenzene 7,800,000 2 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd Isopropyltoluene ne nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd : Only compounds present at concentrations above the laboratory detection limit are included *0 - DC RBCA Tier 0 Risk-Based Screening Levels (June 2011) *1 - DC RBCA Technical Guidance Tier 1, Table 5-9 Risk-Based Screening Level for a Resident Adult, Sub-Surface Soil, Indoor Inhalation, Updated June 2011 *2 - If no DC RBCA screening level was established then the EPA Regional Screening Level (RSL) was utilized for comparison (May 2018) ug/kg = micrograms per kilogram ne - not established nd - not detected above laboratory method detection limit Exceeds Screening Level

24 Table 2 Summary of Soil PAHs s 1400 Shepherd Street NE Washington, DC Sample ID B1-5 B1-15 B1-17 B2-5 B2-15 B2-17 B3-5 B3-15 B3-23 B4-5 B4-10 B4-23 B5-5 B5-15 B5-27 B6-5 B6-10 B6-20 Sample Date 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 Screening Level* Soil PAHs ug/kg * ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Benzo[b]fluoranthene 3,460,000 1 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 516 nd nd Pyrene 1,800,000 2 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 491 nd nd 2-Methylnaphthalene 240,000 2 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 9,690 Naphthalene nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 8,650 : Only compounds present at concentrations above the laboratory detection limit are included *1 - DC RBCA Technical Guidance Tier 1, Table 5-9 Risk-Based Screening Level for a Resident Adult, Sub-Surface Soil, Indoor Inhalation, Updated June 2011 *2 - If no DC RBCA screening level was established then the EPA Regional Screening Level (RSL) was utilized for comparison (May 2018) mg/kg = milligrams per kilogram ug/kg = micrograms per kilogram ne - not established nd - not detected above laboratory method detection limit Exceeds Screening Level

25 Table 3 Summary of Soil TPH s 1400 Shepherd Street NE Washington, DC Sample ID B1-5 B1-15 B1-17 B2-5 B2-15 B2-17 B3-5 B3-15 B3-23 B4-5 B4-10 B4-23 B5-5 B5-15 B5-27 B6-5 B6-10 B6-20 Sample Date 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 Screening Level TPH mg/kg * mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg Gasoline-Range Organics 54 1 nd nd nd nd nd nd 0.29 nd nd nd nd nd Diesel-Range Organics nd nd nd nd nd nd nd nd nd nd nd nd 85 nd nd 95.8 nd 106 : Only compounds present at concentrations above the laboratory detection limit are included *0 - DC RBCA Tier 0 Risk-Based Screening Levels (June 2011) *1 - DC RBCA Technical Guidance Tier 1, Table 5-9 Risk-Based Screening Level for a Resident Adult, Sub-Surface Soil, Indoor Inhalation, Updated June 2011 *2 - If no DC RBCA screening level was established then the EPA Regional Screening Level (RSL) was utilized for comparison (May 2018) mg/kg = milligrams per kilogram ug/kg = micrograms per kilogram ne - not established nd - not detected above laboratory method detection limit Exceeds Screening Level

26 Table 4 Summary of Soil Metals s 1400 Shepherd Street NE Washington, DC Sample ID B1-5 B1-15 B1-17 B2-5 B2-15 B2-17 B3-5 B3-15 B3-23 B4-5 B4-10 B4-23 B5-5 B5-15 B5-27 B6-5 B6-10 B6-20 Sample Date 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 8/9/2018 Screening Level RCRA 8 Metals mg/kg * mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg Arsenic nd nd nd nd nd nd nd nd nd 19.7 nd nd nd nd nd nd nd Barium 15, nd 17.0 nd nd nd nd nd nd Total Chromium ne nd nd nd nd nd Lead nd Mercury (elemental) nd nd nd nd 0.12 nd nd nd nd 0.10 nd nd nd : Only compounds present at concentrations above the laboratory detection limit are included *1 - DC RBCA Technical Guidance Tier 1, Table 5-9 Risk-Based Screening Level for a Resident Adult, Sub-Surface Soil, Indoor Inhalation, Updated June 2011 *2 - If no DC RBCA screening level was established then the EPA Regional Screening Level (RSL) was utilized for comparison (May 2018) mg/kg = milligrams per kilogram ug/kg = micrograms per kilogram ne - not established nd - not detected above laboratory method detection limit Exceeds Screening Level

27 Table 5 Summary of Groundwater 1400 Shepherd Street NE Washington, DC Sample ID B2 B5 B6 Sample Date 8/9/2018 8/9/2018 8/9/2018 Screening Level GW VOCs ug/l * ug/l ug/l ug/l Benzene , Ethylbenzene ,540 Naphthalene nd 614 Toluene ,580 11,600 1,2,4-Trimethylbenzene ,200 2,770 1,3,5-Trimethylbenzene tert-amyl alcohol (TAA) nd 270 nd sec-butylbenzene 2,000 3 nd 61.3 nd Isopropylbenzene (Cumene) nd 76.6 nd 4-Isopropyltoluene ne nd 122 nd n-propylbenzene Xylenes (total) 1, ,010 GW PAHs ug/l ug/l ug/l ug/l 2-Methylnaphthalene Naphthalene GW TPH mg/l mg/l mg/l mg/l Gasoline-Range Organics Diesel-Range Organics nd : *1 - DC Risk-Based Corrective Action (RBCA) Technical Guidance, Table 5-9 Risk-Based Screening Level for a Resident Adult, Groundwater, Indoor Inhalation, Updated June 2011 *2 - If no DC RBCA screening level was established then the EPA Region 3 Regional Screening Level (RSL) Summary Table May 2018 Maximum Contaminant level (MCL) was utilized for comparison. *3 - IF EPA MCL is not available then the EPA Region 3 Regional Screening Level (RSL) Summary Table May 2018 Screening Level for Tapwater was utilized for comparison ne - not established nd - not detected above laboratory method detection limit Exceeds Screening Level

28 APPENDIX IV FINAL LABORATORY REPORTS

29 VELAP ID August 2018 Pam Furst ECS-Chantilly Thunderbolt Place, Suite 100 Chantilly, VA RE: HOWARD UNIVERSITY Enclosed are the results of analyses for samples received by the laboratory on 08/10/18 14:45. A more detailed report format is available upon request, which lists the accreditation status for all analytical methods performed. Please visit our website at for a complete listing of our accreditations. If you have any questions concerning this report, please feel free to contact me. Sincerely, Will Brewington President Page 1 of 98

30 Client Sample ID Alternate Sample ID Laboratory ID Matrix Date Sampled Date Received B1-5' Soil 08/09/18 00:00 08/10/18 14:45 B1-15' Soil 08/09/18 00:00 08/10/18 14:45 B1-17' Soil 08/09/18 00:00 08/10/18 14:45 B2-5' Soil 08/09/18 00:00 08/10/18 14:45 B2-15' Soil 08/09/18 00:00 08/10/18 14:45 B2-17' Soil 08/09/18 00:00 08/10/18 14:45 B3-5' Soil 08/09/18 00:00 08/10/18 14:45 B3-15' Soil 08/09/18 00:00 08/10/18 14:45 B3-23' Soil 08/09/18 00:00 08/10/18 14:45 B4-5' Soil 08/09/18 00:00 08/10/18 14:45 B4-10' Soil 08/09/18 00:00 08/10/18 14:45 B4-23' Soil 08/09/18 00:00 08/10/18 14:45 B5-5' Soil 08/09/18 00:00 08/10/18 14:45 B5-15' Soil 08/09/18 00:00 08/10/18 14:45 B5-27' Soil 08/09/18 00:00 08/10/18 14:45 B6-5' Soil 08/09/18 00:00 08/10/18 14:45 B6-10' Soil 08/09/18 00:00 08/10/18 14:45 B6-20' Soil 08/09/18 00:00 08/10/18 14:45 B Nonpotable Water 08/09/18 00:00 08/10/18 14:45 B Nonpotable Water 08/09/18 00:00 08/10/18 14:45 B Nonpotable Water 08/09/18 00:00 08/10/18 14:45 As a NELAP accredited laboratory, MSS can provide a certification list upon request. Page 2 of 98

31 B1-5' (Soil) VOLATILE ORGANICS BY EPA METHOD 8260B (GC/MS) Acetone ND ug/kg dry /13/18 08/13/18 13:57 GM tert-amyl alcohol (TAA) ND ug/kg dry /13/18 08/13/18 13:57 GM tert-amyl methyl ether (TAME) ND ug/kg dry /13/18 08/13/18 13:57 GM Benzene ND ug/kg dry /13/18 08/13/18 13:57 GM Bromobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM Bromochloromethane ND ug/kg dry /13/18 08/13/18 13:57 GM Bromodichloromethane ND ug/kg dry /13/18 08/13/18 13:57 GM Bromoform ND ug/kg dry /13/18 08/13/18 13:57 GM Bromomethane ND ug/kg dry /13/18 08/13/18 13:57 GM tert-butanol (TBA) ND ug/kg dry /13/18 08/13/18 13:57 GM 2-Butanone (MEK) ND ug/kg dry /13/18 08/13/18 13:57 GM n-butylbenzene ND ug/kg dry /13/18 08/13/18 13:57 GM sec-butylbenzene ND ug/kg dry /13/18 08/13/18 13:57 GM tert-butylbenzene ND ug/kg dry /13/18 08/13/18 13:57 GM Carbon disulfide ND ug/kg dry /13/18 08/13/18 13:57 GM Carbon tetrachloride ND ug/kg dry /13/18 08/13/18 13:57 GM Chlorobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM Chloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM Chloroform ND ug/kg dry /13/18 08/13/18 13:57 GM Chloromethane ND ug/kg dry /13/18 08/13/18 13:57 GM 2-Chlorotoluene ND ug/kg dry /13/18 08/13/18 13:57 GM 4-Chlorotoluene ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2-Dibromo-3-chloropropane ND ug/kg dry /13/18 08/13/18 13:57 GM Dibromochloromethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2-Dibromoethane (EDB) ND ug/kg dry /13/18 08/13/18 13:57 GM Dibromomethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2-Dichlorobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM 1,3-Dichlorobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM 1,4-Dichlorobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM Dichlorodifluoromethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1-Dichloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2-Dichloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1-Dichloroethene ND ug/kg dry /13/18 08/13/18 13:57 GM cis-1,2-dichloroethene ND ug/kg dry /13/18 08/13/18 13:57 GM As a NELAP accredited laboratory, MSS can provide a certification list upon request. Page 3 of 98

32 B1-5' (Soil) VOLATILE ORGANICS BY EPA METHOD 8260B (GC/MS) (continued) trans-1,2-dichloroethene ND ug/kg dry /13/18 08/13/18 13:57 GM Dichlorofluoromethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2-Dichloropropane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,3-Dichloropropane ND ug/kg dry /13/18 08/13/18 13:57 GM 2,2-Dichloropropane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1-Dichloropropene ND ug/kg dry /13/18 08/13/18 13:57 GM cis-1,3-dichloropropene ND ug/kg dry /13/18 08/13/18 13:57 GM trans-1,3-dichloropropene ND ug/kg dry /13/18 08/13/18 13:57 GM Diisopropyl ether (DIPE) ND ug/kg dry /13/18 08/13/18 13:57 GM Ethyl tert-butyl ether (ETBE) ND ug/kg dry /13/18 08/13/18 13:57 GM Ethylbenzene 6.3 ug/kg dry /13/18 08/13/18 13:57 GM Hexachlorobutadiene ND ug/kg dry /13/18 08/13/18 13:57 GM 2-Hexanone ND ug/kg dry /13/18 08/13/18 13:57 GM Isopropylbenzene (Cumene) ND ug/kg dry /13/18 08/13/18 13:57 GM 4-Isopropyltoluene ND ug/kg dry /13/18 08/13/18 13:57 GM Methyl tert-butyl ether (MTBE) ND ug/kg dry /13/18 08/13/18 13:57 GM 4-Methyl-2-pentanone ND ug/kg dry /13/18 08/13/18 13:57 GM Methylene chloride ND ug/kg dry /13/18 08/13/18 13:57 GM Naphthalene ND ug/kg dry /13/18 08/13/18 13:57 GM n-propylbenzene ND ug/kg dry /13/18 08/13/18 13:57 GM Styrene ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1,1,2-Tetrachloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1,2,2-Tetrachloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM Tetrachloroethene ND ug/kg dry /13/18 08/13/18 13:57 GM Toluene 27.8 ug/kg dry /13/18 08/13/18 13:57 GM 1,2,3-Trichlorobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2,4-Trichlorobenzene ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1,1-Trichloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,1,2-Trichloroethane ND ug/kg dry /13/18 08/13/18 13:57 GM Trichloroethene ND ug/kg dry /13/18 08/13/18 13:57 GM Trichlorofluoromethane (Freon 11) ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2,3-Trichloropropane ND ug/kg dry /13/18 08/13/18 13:57 GM 1,2,4-Trimethylbenzene 5.5 J ug/kg dry /13/18 08/13/18 13:57 GM 1,3,5-Trimethylbenzene ND ug/kg dry /13/18 08/13/18 13:57 GM As a NELAP accredited laboratory, MSS can provide a certification list upon request. Page 4 of 98

33 B1-5' (Soil) VOLATILE ORGANICS BY EPA METHOD 8260B (GC/MS) (continued) Vinyl chloride ND ug/kg dry /13/18 08/13/18 13:57 GM o-xylene 10.6 ug/kg dry /13/18 08/13/18 13:57 GM m- & p-xylenes 24.6 ug/kg dry /13/18 08/13/18 13:57 GM Surrogate: 1,2-Dichloroethane-d % 08/13/18 08/13/18 13:57 Surrogate: Toluene-d % 08/13/18 08/13/18 13:57 Surrogate: 4-Bromofluorobenzene % 08/13/18 08/13/18 13:57 SEMIVOLATILE ORGANICS BY EPA METHOD 8270D (GC/MS) Acenaphthene ND ug/kg dry /13/18 08/15/18 12:23 WB Acenaphthylene ND ug/kg dry /13/18 08/15/18 12:23 WB Anthracene ND ug/kg dry /13/18 08/15/18 12:23 WB Benzo[a]anthracene ND ug/kg dry /13/18 08/15/18 12:23 WB Benzo[b]fluoranthene ND ug/kg dry /13/18 08/15/18 12:23 WB Benzo[k]fluoranthene ND ug/kg dry /13/18 08/15/18 12:23 WB Benzo[ghi]perylene ND ug/kg dry /13/18 08/15/18 12:23 WB Benzo[a]pyrene ND ug/kg dry /13/18 08/15/18 12:23 WB Chrysene ND ug/kg dry /13/18 08/15/18 12:23 WB Dibenzo[a,h]anthracene ND ug/kg dry /13/18 08/15/18 12:23 WB Fluoranthene ND ug/kg dry /13/18 08/15/18 12:23 WB Fluorene ND ug/kg dry /13/18 08/15/18 12:23 WB Indeno[1,2,3-cd]pyrene ND ug/kg dry /13/18 08/15/18 12:23 WB 2-Methylnaphthalene ND ug/kg dry /13/18 08/15/18 12:23 WB Naphthalene ND ug/kg dry /13/18 08/15/18 12:23 WB Phenanthrene ND ug/kg dry /13/18 08/15/18 12:23 WB Pyrene ND ug/kg dry /13/18 08/15/18 12:23 WB Surrogate: 2-Fluorophenol Surrogate: Phenol-d5 Surrogate: Nitrobenzene-d5 Surrogate: 2,4,6-Tribromophenol Surrogate: 2-Fluorobiphenyl Surrogate: Terphenyl-d % % % % % % 08/13/18 08/15/18 12:23 08/13/18 08/15/18 12:23 08/13/18 08/15/18 12:23 08/13/18 08/15/18 12:23 08/13/18 08/15/18 12:23 08/13/18 08/15/18 12:23 As a NELAP accredited laboratory, MSS can provide a certification list upon request. Page 5 of 98