CleanHarbors Environmental Services, Inc. — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Washington, D.C. Research and Special Programs Administration APR - 5 2000 Director of Regulatory Affairs Mr. Peter W. Egan Ref. No. 99-0230 CleanHarbors Environmental Services, Inc. 1501 Washington Street Braintree, MA 02185 Dear Mr. Egan: This responds to your letter of August 13, 1999, concerning requirements for shipping a hazardous waste mixture under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask about shipment of a waste corrosive liquid that emits a very low level of hydrocyanic acid (HCN). You describe the waste material, called Alodine, as a mixture composed of 99% water, 0.5% chromic acid, 0.5% potassium ferricyanide, and less than 0.18 nitric acid. You have determined that waste Alodine is properly classed and described as RQ Waste Corrosive Liquid, Acidic, Inorganic, n.o.s. (Chromic Acid), 8, UN 3264, PG II. You state that mixture does not meet the definition of a Division 6.1 (poisonous) material. However, over time, Alodine emits very small mounts of HCN, which can accumulate in the headspace of the 55 gallon drums or bulk packagings in which it is transported. You ask if there is an upper limit on the amount of HCN that may accumulate in the headspace of a non-bulk or bulk packaging above which the shipment of waste Alodine would be prohibited under the HMR. Under § 173.22 of the HMR, it is the shipper's responsibility to determine the appropriate class for a hazardous material. Such determinations are not required to be verified by this it does not appe that the he mored or you provided, office. However, 173.21 990230#

Page 2during transportation. accumulate in amounts sufficient to present a safety hazard transportation as a Class 8 material pursuant to the HMR. Thus, waste Alodine may be offered for I hope this information is helpful. If you have further questions, please do not hesitate to contact this office. Sincerely, one A. Cell Thomas G. Allan Senior Transportation Regulations Specialist Office of Hazardous Materials Standards#

Page 3CleanHarbors ENVIRONMENTAL SERVICES, INC. Kürirry 1501 Washington Street, P.O. Box 850327 • Braintree, MA 02185-0327 (781) 849-1800 $134(c) Visit our Website at www.cleanharbors.com 99-0230 Certified Mail - Return Receipt Requested (Z 318 705 979) August 13, 1999 office of Hazardous Materials Standards, DHM-10 MI. Edward M. Mazzullo, Director Research and Special Programs Administration U.S. Department of Transportation Washington, DC 400 7th Street, SW Re: Request for Regulatory Clarification Dear Mr. Mazzullo: Clean Harbors Environmental Services, Inc. (CHESI) is a national provider of hazardous materials and hazardous waste transportationf to request that United States Department Transportation (USDOT) provide contains low levels of clarification of hydrocyanic acid (HCN) . HEST discussed this question with Mr. George Cushmac of your stati on June 22, 1999. Mr. Cushmac asked that CHESI submit its request to the USDOT in writing. CHESI believes that, during shipment, the material described below does not generate vapors in a quantity sufficient to produce a dangerous atmosphere, does not pose a threat to safety, and is therefore acceptable for transportation under USDOT, regulations. described is not CFR 173.21 (e), 49 173.24 (e) (4) (ii) 49 CFR 177.848 (c) ; CHESI'S rationale CFR is presented below. CHESI requests that the USDOT review this rationale, and notify CHESI as to whether or not the USDOT agrees that the material may be offered for transportation pursuant to 49 CFR Subchapter C. "Peoble and Technoloev Protecting and Restoring America's Environment"#

Page 4CleanHarbors* August Edward Mazzullo Page 2 13, 1999 of 4 Background CHESI provides waste transportation services to several customers who involved in materials fabrication, and who utilize chemicals which contain acids and cyanides which have been intentionally mixed together. One such chemical is called Alodine (trademarked), and is used to prepare the surface of certain metals to accept various coatings. A solution of Alodine used for this purpose is typically comprised of 99% water, 0.5% chromic acid, and 0.5% potassium ferricyanide (a complex cyanide) ; the solution may also contain a small amount of nitric acid (~0.1%). The Alodine solution is typically stored in 2500 gallon open pieces of metal may be immersed in the vats as part of a surface tanks vats inside the manufacturing coating process. These vats are located in an open work area, facility personnel work in the immediate area of the vats. evacuate or remove the HCN which slowly evolves from the Alodine. are no special air purifying or ventilation systems in place to CHESI' S customers who this material have performed air monitoring to ensure the safety of their employees. monitoring has shown that the "reaction rate of the potassium an HCN exposure risk to personnel working in the immediate area of ferricyanide and the chromic acid is slow enough that there is not the vats. Eventually the Alodine loses its efficacy and consequently meets the definition of a hazardous waste pursuant to Resource Conservation and Recovery Act. It must then be transferred offsite properly licensed disposal facility. shipment offsite, a proper USDOT shipping description is determined, and the packaging is then Utilizing the criteria for selecting a proper shipping name pursuant to 49 CFR 172,101(12), the proper shipping description for the material is RO Corrosive Liquid, Acidic, Inorganic, n.o.s. (Chromic Acid), Although material potassium ferricyanide, the solution does not meet the defining criteria for in $173.132. Prior to shipment offsite, the material may be stored in the packaging for up to 90 days. In some cases, HCN slowly evolves from the liquid and accumulates in the headspace of the packaging (e.g., 55 gallon drum) • Monitoring of the headspace in several drums indicated HCN concentrations of 12 parts per million (ppm) HCN. In some cases it is possible that the concentration may reach higher levels.#

Page 5CleanHarbors® Edward Mazzullo August Page 3 of 13, 4 1999 Rationale CHESI believes that this type of acidic cyanide solution with a low emission rate would not release hydrocyanic acid in a concentration during transportation. offered for transport in 55 gallon drums with an HCN concentratior "HESI believes that this material may be safely n the headspace ranging up to 250 ppm. 50 ppm as a maximum follows Assuming that a 55 gallon drum is 90% full of the Alodine solution, approximately 5.5 gallons of void space is present in the head of the drum. CHESI has conservatively assumed that the void space is 102 7. 8 gayative Assuming that there is a release of the entire one cubic foot of drum (e.g.. through the bung cap), which contains HCN 250 ppm, the diluted concentration in 25 cubic feet of air space surrounding the top of the drum would equal 10 ppm. Twenty five (25) cubic feet would consist of the air space located within two (2) feet above the drum, and within a two (2) foot radius around the drum. The United States Occupational Health and Safety Administration (OSHA) has established a permissible exposure limit (PEL) of 10 ppm for HCN. The PEL represents the concentration at which an individual can be exposed for eight (8) hours without any adverse effects. CHESI believes that, in the event of a release of air from the headspace of a drum of Alodine during •transportation, dilution of the HCN concentration due to dispersion in the immediately round the top and sides of the drum would be sufficient to remov ny threat of dangerous vapors to individuals within two feet of the drum. Furthermore, in the release of solution from the packaging, "generation of additional HCN from the solution would be that it would not pose an immediate danger to individuals in the area. Waste Alodine solution may also be offered for transortation by CHESI's customers in bulk packaging (e.g., 5000 gallon transport vehicle) • In this case, CHESI believes that a concentration of 10 ppm HCN (OSHA PEL) the headspace of the bulk packaging is acceptable.#

Page 6CleanHarbors® Edward Mazzullo August Page 4 13, 1999 of 4 Request for Guidance CHESI requests that the USDOT provide CHESI responses to the following questions. 1. shipment of the above described Alodine solution in a 55 smaller) container concentration of HCN in the headspace of the packaging 1 or less than 250 ppm prohibited pursuant to 49 CFR 173.21 (e), 49 CFR 173.24 (e) (4) (ii) or 49 CFR 177.848 (c)? 2. Is shipment of an Alodine solution in a . bulk packaging in which the of HCN in the headspace of the ackaging is equal to or less than 10 pm prohibited pursuant to 49 CFR 49 CFR 173.24 (e) (4) (11) 177.848 (c)? If so, what concentration of HCN in the headspace of the bulk packaging would be acceptable? 3. Would shipment of an Alodine solution in a bulk packaging in which the concentration HCN in the headspace is greater than 10 ppm acceptable? is the maximum concentration that would be allowed in the headspace of a bulk packaging? Please direct your response to my attention at the address on the letterhead. Please don't hesitate to contact me at 781-849-1800 extension 1278 if you have an questions or require additional information. Sincerely, At w.f Peter W. Director of Regulatory Affairs Egan cc: George Cushmac, USDOT#