HomeMy WebLinkAbout20029_Shoppes on Innes_DM_20170718DECISION MEMORANDUM
DATE: July 18, 2017
FROM: Jordan Thompson
TO: BF Assessment File
RE: Centerlane Innes Street
1519 and 1539 East Innes Street
Salisbury, Rowan County
BF # 20029-16-080
Based on the following information, it has been determined that the above referenced
site, whose intended use is for no uses other than retail, restaurant, office, parking, and
health-related professional offices, can be made suitable for such uses.
Introduction:
The Brownfields Property is comprised of two parcels (Rowan County Parcel #s 070-002
and 070-118) and a future public ROW totaling 3.44 acres located west of East Innes
Street and east of Faith Road. The Brownfields Property is developed with a medical
office building that was constructed in 1959 in the southern portion (Parcel 070-118) and
was previously developed with an automotive dealership building (Fowler Motors) that
was renovated into a restaurant in the early 2000s. The former automotive dealership
building was demolished in January 2017.
Redevelopment Plans:
The Brownfields Property is proposed to be redeveloped in two phases. Phase I will be
completed in the northern portion of the property and will consist of construction of a
multi-tenant commercial building and associated parking. Additional commercial
development will be completed on the southern portion of the Brownfields property at a
later date to be determined.
Site History:
A 1,000-gallon gasoline UST was reportedly present on Parcel 070-002 of the
Brownfields Property that was installed in 1971 and removed in 1979; however, no UST
closure records or location of the former UST have been identified. During Site grading
and building demolition, no evidence of a former UST basin was identified on Parcel
070-002.
In February 2016, two groundwater samples were collected to investigate
potential impacts associated with the former use as an auto repair facility and associated
underground storage tank system that was removed in 1979. The results of the
assessment identified groundwater impacts of tetrachloroethylene (PCE) above 2L
Standards in one temporary monitoring well located south of the former automotive
dealership building.
In November 2016, Brownfields assessment activities were completed in
accordance with an approved Site-Specific Quality Assurance Project Plan (SSQAPP).
The Brownfields assessment activities included soil and groundwater sampling to further
evaluate potential impacts associated with historical uses of the Brownfields Property and
potential for off-site migration of impacts onto the Brownfields Property. Specifically,
soil samples were taken in the locations of six former hydraulic lifts, a former wash pad,
and a UST on the south side of the former automotive dealership building that was
discovered during the November 2016 assessment activities.
No soil impacts above Commercial/Industrial Preliminary Soil Remediation Goals
(PSRGs) were identified during the assessment activities. Additional groundwater
impacts of PCE were documented in the central portion of the Brownfields Property and
significantly higher concentrations of PCE were documented on the southern, upgradient,
portion of the property that are likely migrating from an off-site source. A former
drycleaner, Avalon Cleaners, is located south and upgradient of the Brownfields Property
and is in the DSCA Program.
The former automotive dealership building was demolished in January 2017 and
site grading activities began following demolition and Environmental Management Plan
(EMP) approval by DEQ. The UST that was identified during the November 2016
Brownfields assessment activities was further investigated and believed to be a heating
oil UST. The UST and lifts within the former automotive dealership building were
removed in February 2017 during grading activities and two confirmation soil samples
were collected beneath the base of the UST. Soil impacts were not detected above
NCDEQ Commercial/Industrial PSRGs.
Potential Receptors:
Potential receptors are: construction workers, on-site workers, future residences, visitors,
and trespassers. A receptor survey was completed in March 2017 that did not identify
potential receptors within 1500 ft of the Brownfields Property.
Contaminated Media:
DEQ has evaluated data collected from the following media at the subject property: soil
and groundwater. DEQ relies on the following data to base its conclusions regarding the
subject property and its suitability for its intended reuse.
Soil
Soil samples were collected from the following areas of the Brownfields Property and
analyzed for VOCs, SVOCs, and PCBs between February 2016 and February 2017: six
former hydraulic lifts, a former wash pad, and an orphaned UST discovered during
assessment activities.
Two additional soil samples were collected from the base of the orphaned UST following
removal that were sampled for VOCs and SVOCs.
Soil impacts were not detected on the Brownfields Property above Industrial/Commercial
PSRGs.
The table below demonstrates the hazard quotient of on-site soils based on the highest
concentrations identified across the Site and separately from the confirmation samples
collected at the base of the UST. Based on the planned use of the Brownfields Property
for commercial operations and lack of identified soil impacts above
industrial/commercial PSRGs, soil remediation is not required. Final grade sampling of
open areas will be required within 60 days of final redevelopment of the Brownfields
Property.
Groundwater
The most recent groundwater assessment was conducted in November 2016.
Groundwater impacts of PCE have been detected as high as 590 µg/L in the southern,
upgradient portion of the Brownfields Property that is migrating from an offsite source.
A temporary monitoring well was installed adjacent to the planned location of a
commercial building that detected PCE at 49 µg/L.
A VISL calculator was completed for the Brownfields Property as a whole, and for the
vicinity of the planned building. The hazard quotient (HQ) for the Site as a whole was
2.44 and for the vicinity of the planned building of Phase I of development on the
northern portion, was 0.202. Based on the HQ for the vicinity of the planned building,
DEQ has tentatively approved a passive mitigation system with the potential to become
an active system within the planned building and for a minimum of three years’ soil gas
monitoring from DEQ approved sentry point. DEQ Brownfields has notified the PD that
a separate mitigation plan, with the potential for an active mitigation system, may be
required for any future buildings on the Brownfields Property. The table below
demonstrates both the highest concentrations detected and those near the planned
building. Further assessment of the potential for vapor intrusion within the any building
constructed in the southern portion of the Brownfields Property will be required prior to
construction as part of an EMP.
Surface Water
Surface water is not located on the Brownfields Property. The nearest water body is
Town Creek located approximately 2,320 feet north-northwest.
Soil Vapor
No soil vapor testing was completed. As discussed above, a permanent soil gas
point(sentry point) will be installed upgradient of the planned Site building and sampled
for at least three years. The soil vapor point installation plan will be included as part of
the vapor mitigation plan.
Sub-Slab Vapor
No sub-slab vapor testing was completed.
Indoor Air
No indoor air testing was completed. Confirmation indoor air tests will be completed
within the planned building prior to occupancy to ensure the effectiveness of a passive
system.
Risk Calculations
Risk Calculations were performed using Excel worksheets provided by Sandy Mort,
NCDEQ Brownfields Toxicologist. For the purposes of looking at the site spatially,
groundwater impacts were reviewed across the Site and separately in the monitoring well
located adjacent to the planned building. Soil impacts were reviewed for the Site and
separately from the confirmation samples collected at the base of the UST. The risk
calculations indicated the following based on available data, including the following
media: groundwater, residual soil (based on confirmatory soil data), soil gas, indoor air,
and fill soil samples:
Medium Site Area
Non-Residential
LICR HI
Groundwater All 9.2E-6 2.44
Groundwater Planned Building 7.5E-7 0.202
Soil All 3.32E-10 1.70E-4
Soil UST 1.54E-6 3.44E-2
Red shading LICR> 1E-04 or HI> 1.
LICR = Lifetime Incremental Cancer Risk
HI = Hazard Index
Based on the planned reuse of the property for commercial operations and the planned
installation system of a passive mitigation system on the planned building with three year
monitoring of a soil-gas vapor point to activate an active mitigation system, the soil and
groundwater hazard quotients are acceptable. Final grade sampling will be required
during any soil disturbance operations as part of the current EMP and confirmation
indoor air samples will be required as part of a vapor mitigation plan to ensure lack of
potential exposure.
Required Land Use Restrictions:
Based on the site-specific data provided to the Brownfield program, the site reuse is
suitable for the site as long as the agreed upon land use restrictions in the BFA are abided
by.
- No child care, adult care centers or schools
- No groundwater use
- No soil disturbance
- Final grade sampling
- No soil import/export without DEQ approval
- No enclosed building constructed without DEQ approval of vapor intrusion
assessment/mitigation
- Installation of soil-gas monitoring point (sentry point)
- EMP required for redevelopment
- LURU Requirements
- DEQ cannot be denied access
- Deed conveyance of BFA
- Known contaminants on the property may not be kept or stored on-site