|
| |
Frequently Asked Questions (FAQs)
| Q |
What is the Final
Remedy for the Site? |
| A |
The
Final Remedy is a containment remedy which means that the
contaminated materials will remain on the site in a central
location under a specially designed cap. The containment area
will be maintained so that the cap continues to be effective at
containing the lead-contaminated materials safely. More
information on the selected remedy can be found at
Final Decision and
Response to Comments on Selection of Corrective Measure.
|
| |
Go
to Top of Page |
|
Q |
How
long will the remedy take? |
| A |
Implementation of the final remedy (construction activities)
began on May 12, 2008.
On
August 27, 2010, punch list items required for “Substantial Completion”
of the project were completed. The “Final Inspection” (required in the 100 %
Design Plan) took place on Tuesday, August 31, 2010.
|
| |
Go
to Top of Page |
| Q |
What about lead blowing from the site? |
| A |
The design plans call for
precautions to control the amount of dust in the air during the
final remedy. Understandably, no one (including and perhaps,
especially Gould) wants to have any recontamination in the
off-site area as a result of implementation of the Final Remedy.
Off-site verification sampling was performed the week of
November 16, 2009. This sampling program was designed to confirm
that remedial activities did not cause off-site contamination.
As per the USEPA/PADEP
approved Final (100%) Remedial Design Plan, analytical results from the
post-remediation sampling event were compared to the results from the
pre-remediation sampling event to see if there was a statistically
significant increase of more than 100 mg/kg between the pre-construction and
post-construction sample results. For all five properties, the comparison
showed that soil lead concentrations before and after construction were
essentially the same with the largest change in mean soil lead concentration
being less than 20 mg/kg. Statistically, there was not an increase in soil
lead of more than 100 mg/kg at a 95% confidence level. This means that there
is less than a 5% chance that there actually was an increase of more than
100 mg/kg when the sample results indicate that there was not. Therefore, as
per the Final (100%) Design Plan, no additional off-site sampling is
required. A report on the Off-Site Verification Sampling was submitted to
USEPA and PADEP on February 15, 2010, as part of Quarterly Report #14.
(Click here to review the text from the Off-Site
Verification Sampling Report.) The full report may be viewed at the
Marjol Community Relations Office at 502 George Street
in Throop, PA or at the repository in the Throop Borough Building,
located at 436 Sanderson Street in Throop, PA.
|
| |
Go
to Top of Page |
| Q |
What does the ambient air data mean? |
| A |
One way lead in air is measured
is by using high-volume air samplers that run
every six days for a 24-hour period. The site was monitored this
way from 1989 until December 2010. The sampler draws in air
across a filter that collects the dust. This filter is sent to
the lab and the amount of lead in the dust is measured. The
results are in micrograms (1/1,000,000th of a gram) of lead per
cubic meter of air. For comparison, a speck of dust weighs about
10 micrograms, and the average person breathes a cubic meter of
air in about 2 hours. The typical results for lead in air in
Throop are in fractions of micrograms per cubic meter,
equivalent to breathing a dust particle every 3.4 months.
There were four high volume air samplers located at the site, one
sampler at the Mid-Valley Secondary Center on Underwood Road in
Throop, and one sampler located across the river in Dickson
City. The predominant wind direction at the site is from the
west and northwest. One sampler at the site was located in the
predominant upwind direction (HV-4), and the other three
samplers at the Site were located in the predominant downwind
direction (HV-1, HV-2, and HV-3). The Dickson City air monitor
provided background air data. Click here
to review the December 9, 2010, 24-hour ambient air lead data.
(Click here to review additional
information on air monitoring during construction activities.)
|
| |
Go
to Top of Page |
| Q |
Where can I get information about the Site or about
the clean up? |
| A |
There are many ways you can obtain
information. This web site is hosted by Gould, owner of the
Marjol Site. If you would like to contact Gould’s Community
Relations Representative, Lisa Ayers, you may do so by e-mail at
layers@advancedgeoservices.com
or by
telephone 570.383.9313. You may also contact the EPA or PADEP project
managers for the Marjol Site. For their information,
click here.
|
| |
Go
to Top of Page |
| Q |
What is considered “background lead” in yards for this area? |
| A |
Lead is found naturally in soil; therefore, there will always be
some lead in the soil in our yards. “Background” is a level that
varies based on many things, such as the area you live in, the
age of the houses, and proximity to roadways. “Background” for
the Throop area would be in the range of 300 to 350 ppm. This is
what would be expected for an average soil lead level for a yard
with an older home with the samples being taken outside of the
drip zone (the area closest to the house). It will be less for
the properties that had soil removed in 1988 to 1992 since the
replacement soils had lead concentrations below 50 ppm.
|
| |
Go
to Top of Page |
| Q |
What impact has Marjol had on the groundwater at the site?
|
| A |
In the vicinity of
the Marjol site, groundwater is found in a mine pool, about 200
feet below the ground surface. During the Mine Subsidence
Investigation in 1998, samples from the Mine Pool were collected
and tested for lead. Both the total and dissolved lead
concentrations in groundwater samples from four of the five
sample locations were below the laboratory detection limit of
0,8 µg/l. The total lead sample result for the fifth
sample location was 0.99 µg/l, which is well below the USEPA
Action Level for Lead of 15 µg/l; the dissolved lead result for
this fifth sample location was below the detection limit.
These results show that lead from the Site is not dissolving and
migrating downward at measurable levels. There is no
groundwater remediation required under the Final Decision. |
| |
Go
to Top of Page |
If your question is not listed
on this page, please contact us so we can get an
answer for you.
|
Page Last Modified
Sunday July 29, 2012 09:05:59 PM
|
