UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

Mr. Karluss Thomas 

Senior Director 

AUG 18 Z014 

Silicones Environmental, Health, and Safety Center 

American Chemistry Council 

700 2nd Street N.E. 

Washington, D.C. 20002 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

Re: Testing Consent Order for Octamethylcyclotetrasiloxane CD4) (CASRN: 556-67-2; 40 

C.P.R. 799.5000; EPA-HQ-OPPT-2012-0209) 

Dear Mr. Thomas: 

This letter is in response to your June 27, July 23, and August 1, 2014, letters requesting a 

modification in the schedule for delivery of the Study Plan to the U.S. Environmental Protection 

Agency (EPA) for the Testing Program set out in the April4, 2014, Enforceable Consent 

Agreement (ECA) for Environmental Testing for Octamethylcyclotetrasiloxane (D4) between 

EPA and five manufacturers ofthe chemical (the ECA Signatory Companies). As you know, the 

Study Plan was due to the EPA by August 2, 2014, (as per the ECA, § IX.A ... no more than 

120 days after the effective date), with subsequent Quality Assurance Project Plans (QAPP) due 

to the EPA by October I, 2014 (as per the ECA, § IX.A ... no more than 180 days after the 

effective date). 

The Silicones Environmental, Health, and Safety Center (SEHSC), in its role as Principal Test 

Sponsor for the ECA Signatory Companies, requested by the letters noted above, that the 

deadline for submission of the Study Plan be extended to April 2, 2015, based on the amount of 

time needed to identify and secure the cooperation of the requisite wastewater treatment plants 

(WWTP) that meet the criteria specified in the ECA. These challenges were discussed during a 

July 15, 2014, meeting between the EPA, the SEHSC, and the ECA Signatory Companies. At 

the meeting, and in your letters, the SEHSC and the ECA Signatory Companies acknowledged 

that site access agreements and Study Plans have been completed for four direct discharge sites. 

On August 8, 20 I 4, the SEHSC and the ECA Signatory Companies submitted a Study Plan 

addressing sampling at the four direct discharge sites. The SEHSC has asked that the ECA 

schedule be modified to allow an amended Study Plan addressing the remaining ten third party 

WWTPs to be monitored and amended QAPP be submitted by April2, 2015. 

Internet Address (URLJ • hrtp.//www epa gov 

Recycled/Recyclable • Prmted With Vegetable Otl Based Inks on 100% Postconsumer Process Chlorine Free Recycled Paper 
The EPA has carefully reviewed your proposed modification to the schedule. The SEHSC and 

the ECA Signatory Companies have had many months to secure WWTP cooperation and it is not 

clear that a six month delay will, by itself, result in obtaining such cooperation. Therefore, the 

EPA is denying your request. The EPA expects the SEHSC and the EPA Signatory Companies 

to continue to make a good faith effort to secure the cooperation of third party WWTP operators, 

or to propose an alternative approach that will achieve the objectives of the ECA. 

If you have any questions, please contact Heather Njo of my staff at 202-564-2574 or at 

njo.heather@epa.gov. 

Sincerely, 

WVvt~~ '/ V .... Wendy Cleland-I-Iamnett, Director 

~ Office of Pollution Prevention and Toxics