22053_Carolina Coach_Dec Memo_20210726

DECISION MEMORANDUM
DATE: July 26, 2021
FROM: Holly Samaha-Smith, PE
TO: BF Assessment File
RE: Carolina Coach Co.
1208 South Blount Street
Raleigh, Wake County
BF # 22053-18-092
Based on the following information, it has been determined that the above referenced
site, whose intended use is for no uses other than multi -family residential
(condominiums), office, retail, parking and associated amenity uses, and with prior
written DEQ approval, other commercial uses, can be made suitable for such uses.
Associated amenity uses may include pools, clubhouses, courtyards, common areas,
recreation areas.
Introduction:
The Brownfields Property was formerly comprised of two parcels totaling 3.86 acres.
These parcels were assigned Wake County Tax Parcel Identification Number (PINs)
1703737525 and 1703738750 with the addresses of 1201 & 1208 S. Blount Street. These
two parcels were recombined into one parcel on effective January 3, 2019 under active
PIN 1703738654 and the address 1208 S. Blount Street. The original PINS were retired,
and the acreage was corrected to 3.84 acres after recombination. The Brownfields
Property is located at the southern portion of Downtown Raleigh, north of the intersection
of the I-40 and Hammond Road interchange.
The Prospective Developer is Stanley Martin Homes, LLC, a manager -managed,
registered North Carolina Limited Liability Corporation with an official corporate
mailing address of 11710 Plaza America Drive, Suite 1100, Reston, VA. The local
Raleigh, NC office for Stanley Martin Homes, LLC is located at 4020 Westchase Blvd,
Suite 470, Raleigh, NC 27607. The Raleigh Division President of Stanley Martin Homes,
LLC is W. Hampton Pitts. Their contact person is Brian Ketchem, Director of Land,
Stanley Martin Homes, LLC at the local Raleigh address. SM Raleigh, LLC purchased
the Brownfields Property on December 21, 2018, and changed names to Stanley Martin
Homes, LLC, effective February 21, 2021. An affidavit changing the Prospective
Developer to Stanley Martin Homes, LLC was submitted to the Brownfields Program on
July 22, 2021.
Redevelopment Plans:
The Prospective Developer intends to redevelop the site with approximately 100 multi-
family residential condominium units. The development includes parking, private alleys,
a centrally located shared amenity area, and a retail store. Other commercial uses may be
Carolina Coach Co./22053-18-092/26July2021

incorporated into the redevelopment plan with prior written DEQ approval. Construction
has not yet commenced but is expected to start no earlier than 2022.
Site History:
The Brownfields Property was developed in 1939 and may have been occupied by
Sanders Ford. Carolina Coach Co. purchased the Brownfields Property from William
Sanders in December 1969, but it had been operating at this location as Carolina Coach
Company (aka Carolina Trailways) for bus maintenance, fueling, and administrative
activities since at least 1941. Vehicular repairs were conducted in the former buildings
along the northern edge along Bragg Street and in the central portion of the Brownfields
Property. Bus washing operations took place in the south-central area of the Brownfields
Property with bus parking to the east of the bus washing and a new car storage lot to the
west. A boiler room was located immediately adjacent to west of the bus washing
facilities. Carolina Coach handled waste streams including tetrachloroethylene (PCE)
and non -halogenated solvents.
The southwestern area of the Brownfields Property at the corner of S. Blount and Branch
Streets was a sandwich shop and a motor freight station from prior to 1950 until
sometime prior to 1972, where these uses were replaced by a "New Car Warehouse",
likely associated with Sanders Ford.
Greyhound Lines, Inc. of Dallas, Texas acquired Carolina Coach in 1997, and
maintenance operations ceased in 2009. The site has been vacant since that time. All
onsite structures were razed in 2014-2015, and remnant concrete pads and asphalt
parking currently remain at the site.
Historically, 21 known underground storage tanks (USTs) were installed at the site from
approximately 1956 through 1989, each of which has been removed or closed in -place
from 1988 through 2018. An additional 2 USTs are suspected to be located on the
western edge of the Brownfields Property and partially under S. Blount Street. Soil
contamination was initially discovered in 1989 during the in -place closure of four
10,000-gallon diesel USTs located on the east side of the bus wash building on the
southern portion of the Brownfields Property. Petroleum -related constituents were
detected in soil samples, and approximately 485 tons of impacted soil was excavated to
the extent feasible without endangering the structural integrity of the bus wash building
or encroaching the Branch Street easement. A Notice of Violation (NOV) was issued on
August 29, 1991, but further information about the NOV isn't available.
The Brownfields Property was assigned Incident No. 5051 by the Division of Waste
Management (DWM) Underground Storage Tank Section for a petroleum release
originally discovered in 1992. In total, three releases from diesel UST systems have been
reported between 1992 and 2001. At the direction of DWM, free product removal
activities were initiated in August 2002 and continued through August 2009. A total of
eleven aggressive fluid -vapor recovery events were performed, and a total of 655 gallons
of product (vapor and liquid) were removed. In October 2019, an assessment for free
product was conducted in an existing well on the southern, downgradient property line.
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No free -phase petroleum product was noted in the groundwater sample collected and no
petroleum odors were noted.
Communication from the City of Raleigh Public Utilities Department to Carolina
Trailways at 1201 S. Blount Street dated October 15, 2001 notes that a fuel pump was
located in the bus wash bay and needed to be relocated to prevent an inadvertent release
to the sanitary sewer and collection system. In response, an oil -water separator was
installed in December 2005.
A Phase II Environmental Site Assessment conducted at the Brownfields Property in
December 2013 confirmed the presence of petroleum -impacted soils, petroleum -impacted
groundwater, and petroleum free product on the water table on the southern property
boundary. There is an indication that petroleum contaminants extend beyond the southern
property boundary in groundwater based on sampling conducted at a monitoring well on
the other side of Branch Street. However, monitoring for free product conducted in 2019
did not indicate that measurable free product remained on the water table at that location.
In summer 2018, four closed in -place diesel USTs and one oil -water separator on the
southern portion of the site were removed and approximately 6,425 tons of petroleum -
impacted soil were excavated. The depth of the excavation ranged from 18 to 21 feet
below ground surface (ft bgs). The excavation was extended to the property boundary and
was limited by the presence of Branch Street. Prior to backfilling, 850 pounds of
pelletized Oxygen Release Compound was broadcast across the base of the excavation.
To prevent the backfill in the excavation from commingling with the remaining
petroleum contamination, the southern sidewall of the excavation, along the site
boundary, was covered by a six -millimeter -thick polyethylene sheeting. The excavation
was then backfilled starting with approximately three feet of riprap stone followed by
smaller ABC stone, both of which were imported from Wake Stone Corporation. The
stone was covered with approximately 1,600 cubic yards of soil from the original
excavation. This soil was segregated based on field screening, and composite samples
analyzed for VOCs, SVOCs, EPH, VPH, lead, and chromium confirmed that the
segregated soil meets NCDEQ soil quality standards for reuse. Approximately 3,800
cubic yards of recycled concrete from Elite Waste Services and process fill from Wake
Stone Corporation filled the remaining extent of the excavation.
In addition to petroleum compounds, analytical data indicates the presence of chlorinated
solvents and metals in soil and groundwater above regulatory action levels.
Potential Receptors:
Potential receptors are: construction workers, on -site workers, future residents, visitors,
animals, and trespassers.
Contaminated Media:
DEQ has evaluated data collected from the following media at the subject property: soil,
groundwater, and sub -slab vapor. DEQ relies on the following data to base its
conclusions regarding the subject property and its suitability for its intended reuse.
Carolina Coach Co./22053-18-092/26July2021

Soil
Soil samples were collected at the site during multiple events spanning from 1989 to
2018. These samples represent soil from across the site and up to depths of 20 ft bgs.
Samples were typically analyzed for some or all of the following contaminants,
depending on the sampling event: volatile organic compounds (VOCs) by EPA Method
8260, semi -volatile organic compounds (SVOCs) by EPA Method 8270, chromium and
lead by EPA Method 6010, petroleum constituents by Massachusetts Department of
Environmental Protection (MADEP) volatile petroleum hydrocarbons (VPH) and
extractable petroleum hydrocarbons (EPH), and total petroleum hydrocarbons by EPA
Method 8015.
Residual soil contaminants at the Brownfields Property in excess of DWM Residential
Preliminary Soil Remediation Goals (PSRGs) include ethylbenzene (non -detect [ND] to
8.5 milligrams per kilogram (mg/kg)) and naphthalene (ND to 22.5 mg/kg). Petroleum
hydrocarbons in residual soil in excess of PSRGs include C5-C8 aliphatics (ND to 210
mg/kg), C9-C12 aliphatics (ND to 700 mg/kg), C9-C18 aliphatics (ND to 1,620 mg/kg),
C9-C 10 aromatics (ND to 250 mg/kg), C9-C 12 aromatics (ND to 520 mg/kg), C9-C 18
aromatics (ND to 260 mg/kg), and C11-C22 aromatics (ND to 1,100 mg/kg). One
residual soil sample concentration of total petroleum hydrocarbon diesel range organics
(TPH-DRO) was detected at 107 mg/kg at 17 ft bgs, which is above the DWM action
level of 100 mg/kg. However, this area was subjected to in -situ chemical oxidation
measures, covered with polyethylene sheeting, and was backfilled to grade after the 2018
excavation.
Groundwater
Monitoring wells at the Brownfields Property were sampled one to two times per year
between 1990 and 1996, and were sampled annually from 2000 to 2009. Groundwater
samples were generally analyzed for VOCs by EPA Method 602, SVOCs by EPA
Methods 601 or 625, and petroleum hydrocarbons by EPA Method 624. Maximum
concentrations exceeding NC 2L Groundwater Standards (2Ls) were detected at MW-4 in
1995 for benzene (860 micrograms per liter (µg/L)), at MW-4 in 1993 for chlorobenzene
(358 µg/L,), at MW-4 in 1994 for 1,2-dichlorobenzene (262 µg/L,), at MW-4 in 1993 for
1,4-dichlorobenzene (45 µg/L), at MW-4 in 2007 for 1,2-dichloroethane (1.7 µg/L), at
MW-1 in 2007 for 1,2-dichloropropane (34 µg/L), at MW-9 in 1996 for naphthalene (465
µg/L), and at MW-7 in 2005 for trichloroethylene (TCE; 76 µg/L). Petroleum
hydrocarbons C5-C8 aliphatics, C9-C12 aliphatics, C9-C18 aliphatics, C9-10 aromatics,
and C11-22 aromatics were also detected above 2L standards in MW-1, MW-4, and MW-
9. MW-9 was last sampled in 2000. Free product was observed in the well during
sampling events between 2004 and 2013.
Groundwater was most recently sampled in 2013 and 2015. Samples were analyzed for
VOCs by EPA Methods 6200 and 8260, SVOCs by EPA Methods 625 and 8270, and
MADEP EPH and VPH. Some wells were also analyzed for chromium and lead by EPA
Methods 303 and 3050, pesticides by EPA Method 8081, and polychlorinated
biphenyls by EPA Method 8082. Maximum concentrations exceeding 2L standards
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measured at the site include chromium at GP-25 (605 µg/L), lead at GP-22 (949 µg/L),
and tetrachloroethene at GP-26 (1.5 µg/L,). For constituents that were previously
analyzed, concentrations have generally decreased over time as presented in Exhibit 2.
Surface Water
Surface water is not located on the Brownfields Property.
Soil Gas
Soil gas data has not been collected at this time, instead relying on sub -slab vapor
collected below existing slabs.
Sub -Slab Vapor
At the request of the NC Brownfields Program, sub -slab vapor samples were collected in
October 2019 from the areas of the 12 proposed multi -residential buildings below
concrete slabs remaining after the buildings had been demolished years before. Vapor
Pins were installed to a depth of 16 inches bgs, and samples were collected using Summa
canisters and analyzed by USEPA Method TO-15. One TCE sample (45 µg/m3)exceeded
the DWM Residential Vapor Intrusion Screening Level (VISL- July 2020) of 14 µg/m3.
The compounds 1,3-dichlorobenzene, cis-1,2-dichloroethylene, ethanol, and
trichlorofluoromethane were also detected and reported in Exhibit 2, but they do not have
established VISLs.
Indoor Air
Indoor air data were not collected because all buildings on the Brownfields Property were
demolished by spring 2015.
Risk Calculations
Risk calculations were performed using the current DEQ Risk Calculator (July 2020
version). For the purposes of looking at the site spatially, the site was assessed on a site -
wide basis.
Based on available data in groundwater, residual soil, and sub -slab vapor, the risk
calculations indicated the following:
Carolina Coach Co./22053-18-092/26July2021

Risk for Individual Pathways 1
Version Date:. July 2020
Basis: May 2020 EPA RSL Table
Site ID: 22053-18-92
Exposure Unit ID: Site -Wide
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicRis
Hazard Index
Riskexceeded?
Soil
1.4E-05
7.6E+00
YES____
Resident
..
..
... ........
Groundwater Use*
8.6E-04
7.8E+01
YES
Soil
3.2E-06
1.4E+00
YES
Non -Residential Worker
....... ........... .............................................
..........
.... I ............... ...........I
.......................
Groundwater Use*
2.1E-04
I 1.SE+01
YES
Construction Worker
Soil
5.0E-07
2.7E-01
NO
il
6
1:c�
Recreator/Trespasser
....... ....... ....... .............
..... ...
. ...3.:NC
...... ........
... cs..........
Surfa eoR'ater*.......
VAPORINTRUSION CALCULATORS
Receptor
Pathway
.............. .................. .......................................................................
Groundwater to Indoor Air
CarcinogenicRisk
.........
9.1E-05
Hazard Index
.................. .................
1.0E+02
Riskexceeded?
.........I ......,..........
YES
Resident
..................................... ............... ..............
Soil Gas to Indoor Air
............... ..............................
1.9E-05
..............
1AE+00
......................
YES
...............................................................................................................................................................................
Indoor Air
NC
NC
NC
Groundwater to Indoor Air
1.6E-05
2.5E+01
YES
Non -Residential Worker
Soil Gas to Indoor Air
.............................................................................................
1.3E-06.........
............................................................................
.... 8.3E-02
NO
Indoor Air
NC
NC
NC
As indicated by the risk calculator's output, soil use for resident, non-residential worker,
and recreator/trespasser scenarios indicate an exceedance of the non -cancer hazard index
of 1.0. Groundwater use exceeds both the carcinogenic risk of 1 E-4 and non -cancer
hazard index for residential and non-residential worker scenarios. Limitations on direct
contact with soil and groundwater are included in the LURs of the Brownfields
Agreement.
Additionally, a vapor intrusion mitigation system (VIMS) will need to be installed since
the calculated soil gas to indoor air output exceeds the non -cancer hazard index of 1 for
the residential exposure scenario, as does the groundwater to indoor air calculations for
both residential and non-residential exposure scenarios.
Required Land Use Restrictions:
Land use restrictions (LURs) will include the standard land use definitions, requirement
for an Environmental Management Plan (EMP), groundwater, soil disturbance, known
contaminants, access, notification, and vapor intrusion LURs.
Based on the site -specific data provided to the Brownfield program, the site can be made
suitable for the proposed reuses as long as the agreed upon land use restrictions in the
BFA are abided by.
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Property Management Issues:
An Environmental Management Plan has not been submitted to date, so a review of the
plan will need to be conducted prior to construction. Construction is anticipated to begin
no sooner than 2022. A VIMS is necessary for this new residential redevelopment;
however, the details for the VIMS have not been discussed yet with the PD team, nor has
a VIMS design been submitted for our review. This would be installed during new
construction, which is expected to commence in early 2022.
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