HomeMy WebLinkAboutFW_ Bowman Gray Stadium Project Update_Action PlanFrom:Ghiold, Joe
To:Marks, Cheryl
Subject:FW: Bowman Gray Stadium Project Update/Action Plan
Date:Wednesday, June 10, 2015 9:43:21 AM
Cheryl,
At the request of Michael Scott, I am sending you this e-mail for your review and consideration.
Thank you,
Joe Ghiold
NC Brownfields Project Manager
From: Joan Smyth [mailto:joan@smithgardnerinc.com] Sent: Tuesday, June 09, 2015 6:18 PMTo: Daphne Jones; Keith Huff; Ben RoweCc: Ledezma, Rosalba A.; James T. Mitchell; millsrw@wssu.edu; gravescc@wssu.edu; Ghiold, Joe;Watkins, JasonSubject: Bowman Gray Stadium Project Update/Action Plan
All –
This email is sent to provide a preliminary summary of our activities from last week and today
regarding the Bowman Grady Stadium project. Last week, in response to elevated concentrations of
methane found in the subsurface adjacent to historic landfills at the Bowman Gray property, we
began surface emission testing of the property. As I have explained previously, the surface emission
testing is performed with a Flame ionization detector (FID) that reads in parts per million of
methane. This is more sensitive than a typical gas meter that reads in % of methane. As a refresher
5% methane is equal to 100% of the lower explosive limit. Some of the subsurface readings adjacent
to the landfill units exceed 40% methane.
Surface Emission Results
As of yesterday afternoon we have completed the surface emission testing of the entire property
including all buildings/parking areas/fields/etc. All results were non-detectable or below 1% of the
lower explosive limit with the following exception:
1) Our team identified a crack in the soil immediately west of the SW Lot that appeared to
be over the sewer line and adjacent to the light poles. This crack was approximately 10 feet
long and 1 inch wide. Emissions from the crack were 100% of the lower explosive limit.
Our crew patched the crack with hydrated bentonite after identification. Readings after patching
were 509 parts per million (~1% of the lower explosive limit). The next day as we continued our
surface emission testing, we rechecked the crack. The crack had extended approximately 2-feet. We
patched the new area with hydrated bentonite and brought in two loads of soil to place on top of
the entire length of the crack. The soil was spread, seeded and strawed. As of this afternoon, the
emissions in this area are 6000 parts per million (12% of the lower explosive limit). I will be
discussing options for dealing with this in the morning with the City.
Home Testing
We have performed emission testing (at the request of the residents) within two houses to the west
of the SW Lot. Neither house had detectable gas levels within the house our around the
foundation. Of these houses, the house we tested this afternoon (at the landfill end of Gholson Ave
S. E.) had a crack in the driveway with readings of 2900 parts per million (equal to 5.8% of the lower
explosive limit).
I will be discussing options for dealing with this in the morning with the City.
Additional Soil Gas Probes in Eastern Permitted Landfill area
We also advanced three soil gas probe locations adjacent to the southern property line of the
eastern section of property (along the property line shared with 3RC). These probes were east of
the probe location where we detected 40% of methane. These three new probes had NO detectable
methane. This may indicate the MSW waste disposal was limited to a certain area of this permitted
debris landfill.
For Wednesday and the remainder of the week:
On Wednesday, we will begin performing soil gas survey work in the road right of ways for Diggs
Blvd, Gholson Ave., Fitch St. and Williamson St, from Bruce Street toward the landfill. We will keep
you apprised of our results.
Thanks, and please let me know if you have any questions.
Joan A. Smyth, P.G.
Senior Hydrogeologist
SMITH + GARDNER
14 N. Boylan Avenue
Raleigh, NC 27603
P (919) 828.0577 x221
F (919) 828.3899
C (919) 815.1494