From: David L. Duncklee [firstname.lastname@example.org]
Sent: Thursday, July 07, 2011 9:15 AM
To: Thomas, Lois
Cc: 'Daphne Jones'; email@example.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.
David L. Duncklee, PG, RSM
Office: 919-858-9898 x201
A Professional Geologic and Engineering Corporation