From: David L. Duncklee
[dave@dunckleedunham.com]
Sent: Thursday, July 07, 2011 9:15
AM
To: Thomas, Lois
Cc: 'Daphne Jones';
tdunham@dunckleedunham.com
Subject: Support for EMC's Proposed
Rulemaking re: 1,1-DCE
Dear
Ms. Thomas,
I
am President of Duncklee & Dunham, P.C., a Geological and Engineering
Environmental Consulting firm located in Cary, North Carolina. I
understand the July 14, 2011 EMC meeting will have an agenda item relating to
considering establishing a new groundwater standard for 1,1-dichloroethene
(1,1-DCE) at 350 µg/L, up from the current level of 7 µg/L. I have been
following this case with interest, as it makes sense that North Carolina
groundwater quality standards are based on the most current scientific and
toxicological data available.
I
understand the current 1,1-DCE level of 7 µg/L is based on the lowest of the
standards the Division of Water Quality considers for comparison, in this case
the federal maximum concentration limit (MCL). I understand that the oral
reference dose was changed for 1,1-DCE in 2003, but EPA did not change the MCL
for this constituent, and has no plans to do so because of non-scientific
reasons, e.g. competing workload priorities and administrative costs associated
with the rulemaking. I do not believe it was the legislative intent for
2L standards to use the least value if that value was not calculated based on the
most current toxicological information.
Even
though the state’s toxicologist calculated the groundwater quality standard
should be 350 µg/L in 2004 based on the updated reference dose information, I
understand the Division of Water Quality refused to change the 1,1-DCE
standards because of the way their own 2L rules were written. I am
optimistic the EMC ruling will be based on logic, not adherence to a standard
that no longer has the basis to be set at that level.
Duncklee
& Dunham has had many clients affected by the changes/additions in
groundwater standards and IMACs, often requiring much more money to be spent to
clean up groundwater to meet these standards. It appears that the
regulated community may have to bear considerable additional costs to meet a
standard that has no scientific basis.
On
behalf of the professional geological and engineering staff of Duncklee &
Dunham, P.C. please consider this letter of support for the Rhodia Petition for
the amendment of the current 1,1-DCE groundwater standard to be raised from
7µg/L to 350 µg/L.
Sincerely,
David
L. Duncklee,
PG, RSM
Senior
Hydrogeologist
Mobile:
919-417-9923
Office:
919-858-9898 x201
A Professional Geologic and Engineering Corporation