Air-Tech Environmental, LLC

P. O. Box 12353 $ Research Triangle Park $ NC $ 27709-2353

Telephone: (919) 544-6338

Fax: (919) 572-2203

E-Mail: answers@ipass.net

web: air-tech-environmental.com

July 10, 2013

Howard L. Gilberg

Guida, Slavich & Flores, P.C.

750 North St. Paul Street, Suite 200

Dallas, TX 75201

Re: Stonepeak Ceramics December 2005 Test Report

Dear Mr. Gilberg:

This letter concerns the review of the December 2005 test report of Stonepeak 

Ceramics as referenced above. It supersedes my report dated March 2013. The testing 

company and analytical laboratory are both located in North Carolina. Our focus was 

on the kiln HCI/HF results. The kiln was tested for HCI/HF by Method 26. Method 26A, 

and not Method 26 with its mini-impingers, is best for establishing standards, along with 

Method 320. 

Integrity conducted three sixty-minute tests at the kiln main exhaust stack. I have 

reviewed numerous acid gas stack tests at clay ceramics plants during my lengthy 

career. I have conducted hundreds of HCl tests by Method 26 and Method 26A at 

Brick, Tile, Cement, Boilers and Industrial Furnaces. The reported HF and HCl results 

at Stonepeak are impossibly low. Ceramic tile kilns process tens of thousands of 

pounds of tile at one time containing clay with high chloride and fluoride levels. I cannot

recall ever have non-detect results for HCl and HF. 

It is my professional judgment that the HF and HCl results reported by Integrity reflect

conditions expected in the ambient atmosphere. The moistures of the sampling trains 

are consistent with the sampling of ambient air. While leak checks were reportedly 

performed with success, there are a number of other opportunities that are not required 

to be reported in a stack test that lead to the unexpected and unplanned measurement 

of ambient air, such as the probe not being placed in the proper location in the stack.

AIR TECH
Howard L. Gilberg

Page 2

July 10, 2013

These test results are not acceptable statistically; they are statistical outliers not 

comparable to the HF and HCl results reported by major source floor tile plants in the 

industry to EPA. Those results, as recorded by EPA, are attached to this presentation. 

The raw materials used and the production processes involved at Stonepeak are very 

similar to those found in floor tile plants whose results were reported to EPA, so I

discount this basis for explaining the reported results.

In a handwritten note on page 60 of the Integrity report, it indicates that the stack 

testing was stopped and then restarted one hour and 13 minutes later (9:05 am to 

10:18 am). This is a red flag. The report provides no explanation for this situation. We 

question the validity of a test run that is broken into a 20 minute segment followed by 

over an hour’s delay before a final 40 minutes was run, especially with no explanation 

for the situation. 

There are no production record field notes provided to support the emissions rates 

reported. All we have are emails over two weeks after the testing was completed, which 

is inadequate. The stack test report does not provide records showing that operation of 

the kiln was routine and being run at full capacity or was empty, or anything in between. 

It is not uncommon for kilns with processing problems to be emptied of tile until 

corrections are made. A ceramic kiln not processing ceramic does not have fluorides or 

chlorides in it to evolve as air emissions. The report does not indicate if a bypass stack 

was present. One explanation for HCl and HF measurements reflecting ambient air 

conditions is that a bypass stack might have inadvertently been in use. If it was, the 

Method 26 measurement equipment would have had no opportunity to come in contact 

with, or to measure the kiln exhaust gases during the stack testing. It would have been 

measuring ambient air present in the main exhaust stack.

There was a probe and filter temperature abnormality in the testing and reporting 

procedures, beginning on page 60 of the report. This field data sheet indicates that the 

desired probe and filter temperature was 250oF, as required by the method, but there is 

no indication on the data sheet itself as to whether this was achieved. In addition, there 

is no documentation that the probe and filter temperatures were maintained as required 

throughout the testing runs. If the temperature was not maintained, then the results are 

invalidly biased lower than the actual emissions. This failure of the field technician to 

document the temperatures of the probe and the filter indicates, to me, that those 

temperatures were not maintained during the test. This conclusion is supported by the 

low numbers in the test results. There also was no indication on the data sheet that 

the probe was in the stack. No stack temperature was recorded on the data sheet.
Howard L. Gilberg

Page 3

July 10, 2013

Maybe most critically, there are no means to validate the HF results used because 

there are no HF analytical results reported by Element One, the laboratory. Results are 

provided for HCl and CL only on the M26-A HF-IC data sheets. Setting standards on 

assumed corrections of laboratory data would be inappropriate and arbitrary.

For all of these reasons, I cannot recommend this HF or HCl information be used for 

any regulatory purpose.

Sincerely,

Michael W. Hartman

Managing Director/Principal Scientist

(AT13-0658-GSF)