1910_Brickhaven_AerosolTrialReponse_DIN27587_20170331

March 31, 2017

North Carolina Department of Environmental Quality
Division of Waste Management – Solid Waste Section
217 W. Jones Street
Raleigh, NC 27699‐1646

Attn.: Ed Mussler, Permitting Branch Supervisor

RE: PCB Notification for Riverbend Steam Station CCP Basin Excavation Project

Dear Mr. Mussler,

In response to your letter dated, March 20th, 2017, we understand the determination of
unrestricted use for materials including Coal Combustion Products (CCPs) where there is a
polychlorinated biphenyl (PCB) content of less than 1 part per million (ppm). We have instituted
this rule for all CCP materials that will be accepted for placement at the Brickhaven structural fill
project as regulated under the Toxic Substance and Control Act (TSCA) as well as State standards.

Below, we offer the additional information as requested by the Division:
 Duke Energy has performed voluntary PCB analysis on samples collected as representative
of ash excavated at the Riverbend Steam Station since 2015. In 2015, three (3) quarterly
PCB analyses were performed while <100,000 cubic yards of ash were excavated from
Riverbend and transported by truck to Waste Management’s R&B Landfill in Homer, GA
(May 2015 through September 2015), to Duke Energy’s industrial landfills at Marshall
Steam Station in Mooresville, NC (July 2015 through January 2016), and to Charah’s
Brickhaven Mine in Sanford, NC (October 2015 through February 2016). As excavation
rates increased in late January 2016 with the onset of rail transportation to the Brickhaven
Mine, Duke Energy began implementing a voluntary sampling program that recommended
1 sample/month for monthly ash transport of less than 50,000 cubic yards, 2
samples/month for monthly ash transport of between 50,000 and 100,000 cubic yards, and
3 samples/month for monthly ash transport in excess of 100,000 cubic yards.
Representative sampling was conducted as described from samples taken from the
Riverbend stockpile prior to placement in trucks/rail cars for off‐site transport.

The PCB laboratory analyses of ash samples described above have been performed utilizing
EPA Method 3546 for extraction/preparation and EPA Method 8082 for analysis.
Compared to other EPA extraction methodologies for PCB testing, EPA Method 3546 is the
newer technology that uses a microwave to heat and pressurize a closed vessel containing
the soil sample and the solvent to extract the organics from the soil. This preparation
method is widely used today in the large commercial labs Duke Energy relies on for its
testing needs and is generally considered equivalent to other preparation methods.
Through mid‐March, PCB analyses had been performed on approximately forty (40) ash
samples collected from Riverbend.

 Whereas the previous recommendation for voluntary sampling was to perform the
sampling on a frequency (a certain number of samples per month dependent on volume
transported), revisions to the logistics for ash sample collection in the field are planned to
ensure adequate time for sample analyses to be received and reviewed by Charah prior to
ash being transported from Riverbend to Brickhaven. Currently, the new approach for ash
sampling for PCB analysis involves collecting ash samples on an approximate 400’x400’ grid
at approximately 6‐foot intervals (either with each sequential excavation lift or through use
of geoprobes). This revised plan for lateral and vertical separation of samples will result in
a roughly equivalent number of samples as was collected as part of the original sampling
frequency recommendation while maintaining a representative nature for sampling. As
described below, Duke Energy is making plans to transition from EPA Method 3546 for
sample extraction to EPA Method 3550 or 3540. Duke plans to continue with EPA Method
8082 for sample analysis.

Concerning the lab preparation method for PCB analysis and as mentioned in Bullet #1, EPA
Method 3546 is the newer technology that uses a microwave to heat and pressurize a closed
vessel containing the soil sample and the solvent to extract the organics from the soil.
Method 3540 is the original technology that uses a reflux (Soxhlet) of the organic solvent
over time coming in contact with the soil to efficiently extract the organics from the soil. The
other two methods that can be used are 3550 (which uses ultrasonic disruption of the soil
to extract organics) and 3545 (which is similar to microwave but uses an oven block to heat
the pressurized vessel for the extraction). All the extraction methods are approved and are
generally considered equivalent. When the Duke Laboratory asks a vendor lab for PCB
analysis by EPA Method 8082, the lab is generally free to choose which extraction method
they prefer. Method 3540 is slower and uses a lot of solvent, so that has largely been retired
from commercial labs. Method 3550 also uses more solvent and is labor intensive. EPA
Methods 3545 and 3546 are both automated methods with sophisticated extraction
equipment, and they use much less of the expensive solvent. In general, labs currently
prefer the microwave method for preparation because it is inexpensive to operate even
though the up‐front instrument costs more. All preparation methods are roughly equivalent
in extraction efficiencies, so generally the commercial lab will choose the most efficient
method for their circumstances. Larger commercial labs almost exclusively use the
automated methods since it takes less technicians and chemicals. The commercial labs
Duke Energy relies on for its testing needs do not run EPA Method 3540, and few
commercial labs across the nation still offer this testing method.

However, Duke Energy understands that EPA Methods 3550 (ultrasonic) and 3540
(soxhlet) are the only methods identified under federal regulations for assessing TSCA
applicability. While EPA Method 3546 (microwave) is an approved methodology and while
all sample results to‐date have been non‐detect or well below 1 ppm, Duke is making plans
to transition to either EPA Method 3550 or 3540. This transition in extraction methodology
should help avoid any lack of clarity for determining proper steps, if necessary, in the
future. Duke plans to continue with EPA Method 8082 for sample analysis.

 Through Thursday, 3/30/2017, Charah has transported and placed approximately
3,480,718 tons of CCPs in the structural fill at Brickhaven. About 1,854,235 tons that have
been placed originated from the Riverbend Steam Station CCP basin and dry stack.

 The Duke contact regarding the history of PCBs at the Riverbend Steam Station has been
identified to be Sean DeNeale.
The State may reach Mr. DeNeale at the following:
o Sean DeNeale
Duke Energy – EHS CCP
Engineer III ‐ Waste & Groundwater Programs
Office: (704) 382‐4761
Cell: (704) 617‐2393
Sean.DeNeale@duke‐energy.com

As discussed and directed, Charah will not accept any CCPs for placement in the Brickhaven
structural fill that have a PCB content equal to or greater than 1 ppm. Any material testing higher
than 1 ppm will not be sent to or accepted for placement at the structural fill project in Brickhaven.
The PCB contaminated CCPs will be segregated and held at the ash basin for final determination.

Let us know if you require any further information or have any additional questions.

Sincerely,

Norman E. Divers, III
Director – Engineering, Environmental and Quality
/nd

Cc: Rob Reynolds, Charah
Matt Kingsley, Charah
Project Files