### To: **Jeff Telander From:**  **Dave Reeves Project File**  **Date: March 17,**  **200 8** 

**Re: Mineral Wool**  **Production**

**– Actual versus Allowable Emissions** 

**Source Category**  **Emission Point Format of Primary**  **(MACT) Standard**  **Could Possibly**  **Calculate Allowable?**  **Info Nee ded to** 

**Calculate Allowable**  **Emissions**

Mineral Wool Cupolas Emission Limits: kg PM/ Mg melt kg CO/ Mg melt Yes Amount of melt

Curing Ovens Emission Limit:

kg formaldehyde/Mg melt Yes Amount of melt



### We reviewed all of the reported emissions data in NEI a nd TRI, as well as the emission limits in the Mineral Wool Production MACT standard and state operating permits. In general, all of the emission limits are based on production levels (e.g., mass of pollutant allowed to be emitted per mass of material melted). Even though production levels could be increased at most of the currentl y operating facilities, there are equipment and process limitations on how the melting furnaces (cupolas) are operated

– which limits the potential (allowable) emissions for a given facility

. Market forces also impose production caps on existing facilities and probably account for much of their current excess capacity

. Th e cupolas are considered batch operations, but are run on a continuous or semi

- continuous basis to save time and energy to heat up the furnace for each batch. Because melting operations are the production limiting process at these manufacturing facilities, the reported emissions are representative of the current market and are believed to at the highest level (s ince the overall mineral wool market is declining).

We also reviewed data from the North American Insulation Manufacturers Association (NAIMA) in response to a request for summary MACT compliance test data for mineral wool production facilities. Six facilities reported cupola particulate matter (PM) emissions and three facilities operating bonded lines reported formaldehyde emissions from curing

ovens

– see attached summary table

. The arithmetic average PM emission rate for all cupola PM emissions data is 0.044 pounds PM/ton melt. (We also calculated individual facility averages and mean s and came up with basically the same value.) The average formaldehyde emission rate for all curing oven formaldehyde emissions data is 0.038 pounds formaldehyde/ton m elt. Allowable PM and formaldehyde emission rates under the Mineral Wool MACT standard are 0.1 pounds PM/ton melt and 0.06 pounds/ton melt, respectively . The allowable PM emission rate is approximately

2.3 times higher than the average of the reported PM emission rates (0.1/0.044) . The allowable formaldehyd e emission rate is approximately 1. 6 times higher than the average of the reported formaldehyd e emission rates (0.06/0.038)

. Based on these reported emission rates and the equipment and process limitations, we are recommending that allowable emissions be estimated to be 2 times the actual emissions for each facility

for purposes of the risk modeling. We believe that a 2X factor applied to the most recent reported emissions is realistic and does not grossl y overstate potential emissions.1

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 A B C

**Faci li** **ty Cu**  **po la** **E mis**  **si on** **s (l**  **b PM**  **/t on**  **m el**  **t) Cu**  **ri ng**  **O ven**  **E mi**  **ssi on**  **s (l**  **b fo**  **rmal dehyd** **e/ to**  **n mel**  **t)** Am erroc k Produc ts L P (Nol anv il leP la nt) - Cupol a No

. 1 0. 076 Am erroc k Produc ts L P (Nol anv il leP la nt) - Cupol a No

. 2 0. 096 In dustr ia l In su ltio n Grou p, L LC (form erl y Ow ens Corni ng) - Cu pola Furnac e Outle t 0. 08 In dustr ia l In su ltio n Grou p, L LC (form erl y Ow ens Corni ng) - Cu ring Oven 0. 059 Is ol at ek I nt ernat io nal -C upol a Ba ghouse 0. 008583 Is ol at ek I nt ernat io nal -C upol a Ba ghouse 0. 047476 Is ol at ek I nt ernat io nal -C upol a Ba ghouse 0. 007352 Roc k Wool M anufact uri ng (L eeds, AL ) - No. 1 C upol a 0. 055 Roc k Wool M anufact uri ng (L eeds, AL ) - Curi ng Oven 0. 017 Sl os s I ndust ri es Corp. -C upol a Ba ghous e 0. 049 Thermaf ib er, I nc. (Wabas h, I N) - Cupol a No

. 2 Ba gh ouse Ou tle t 0. 00901 Thermaf ib er, I nc. (Wabas h, I N) - Cupol a No

. 4 Ba gh ouse Ou tle t 0. 00788 Thermaf ib er, I nc. (Wabas h, I N) - Bo nded Curi ng Ov en RT O Ou tle t 0. 037

**AV ER**  **AG E**  **=** 0. 044 0. 038