These amendments to 6 CCR 1007-3, Part 261 are made pursuant to the authority granted to the Hazardous Waste Commission in § 25-15-302(2), C.R.S.
Amendment of Part 261. Appendix IX to Conditionally Delist F006 Hazardous Waste Generated by Photo Stencil located at 4725 Centennial Boulevard in Colorado Springs. Colorado 80919
Appendix IX of Part 261 is being amended at this time to conditionally delist F006 hazardous waste generated at Photo Stencil in Colorado Springs, Colorado. This delisting will allow Photo Stencil to dispose of this waste at a solid waste landfill that meets the requirements of the Colorado Solid Waste Regulations 6 CCR 1007-2, provided it complies with the conditions of the delisting.
On June 17, 2003, the Hazardous Waste Commission ("Commission") tentatively approved Photo Stencil's petition to delist F006 hazardous waste generated at Photo Stencil's manufacturing facility located at 4725 Centennial Boulevard in Colorado Springs, Colorado 80919. Pursuant to the provisions of § 25-15-302(2), C.R.S. and 6 CCR 1007-3, § 260.20(c), a public notice of the tentative decision to approve the delisting was published in the Colorado Register for written public comment. The public comment period closed on August 10, 2003. No comments were received. On August 12, 2003, the Commission voted to make the decision final. The delisting will become effective 20 days after publication in the Code of Colorado Regulations ("CCR") at 6 CCR 1007-3.
Photo Stencil operates a manufacturing facility in Colorado Springs, Colorado for the production of stencils for the computer board and component manufacturing industry. Some of the metal finishing operations conducted by the company are electro forming (i.e., nickel electroplating), metal preparation, ferric chloride etching, and specialty nickel plating. Wastewater that is generated from these operations is treated on-site to remove heavy metals. The process of treating the wastewater generates a wastewater treatment sludge that is classified as a F006 listed hazardous waste. The F006 hazardous waste listing in § 261.31 describes wastewater treatment sludge that is generated from electroplating operations.
The basis for each hazardous waste listing is described in Appendix VII of Part 261. Each listing is based on hazardous constituents that are typically contained in wastes described by the listing. The hazardous constituents that formed the basis for the F006 listing include cadmium, hexavalent chromium, nickel, and cyanide (complexed).
Wastewaters from the electroplating and chemical etching processes are transferred via pipes to a collection tank, pumped into a treatment cone, and then treated with magnesium sulfate and sodium hydroxide to precipitate the metals. Following the treatment process, the liquid is decanted and the resulting sludge is pumped through a filter press forming a filter cake (i.e., a wastewater treatment sludge).
Analytical sampling of the F006 sludge was conducted prior to the submittal of the delisting petition. The electroplating and chemical etching processes do not significantly change on a day-to-day basis. The samples that were collected in support of the delisting petition have been determined to be representative of the waste in question. The Hazardous Materials and Waste Management Division at the Colorado Department of Public Health and Environment (the Division), evaluated the sampling results and the petition to delist the waste in accordance with § 260.22.
With regard to analysis of the constituents that formed a basis for listing the waste as an F006 hazardous waste, the analytical results indicate that the waste did not contain detectable concentrations of cadmium, hexavalent chromium, or complexed cyanide. The results of the analysis further indicate that the waste contains detectable concentrations of nickel. Nickel was detected at and average total concentration of 7,597 parts per million.
Based on health-based risk assessment calculations derived using the general assumptions outlined in the Division's current risk assessment policy, the waste in question has been determined to exceed residential risk-based levels, almost exclusively due to the presence of nickel. However, the concentration of nickel is less than the preliminary remediation goals established by Region 9 of the EPA. Therefore, the Division believes that risk to human health and the environment will be minimized if this waste is managed in a compliant Subtitle D solid waste landfill.
Analytical sampling of the waste also indicated that the waste contained detectable concentration of arsenic, barium, trivalent chromium, copper, and lead. Based on health based risk assessment calculations and average background soil conditions, the Division determined that the waste did not contain concentrations of those metals at levels which would be considered harmful to human health or the environment.
Using TCLP analytical tests, the Division evaluated the potential for hazardous constituents to leach from the waste and contaminate groundwater. The results of the TCLP analysis indicated that arsenic does not show any chemical potential to leach out of the waste. The TCLP analysis also showed that barium, cadmium, total chromium, and lead are well below the maximum concentrations of contaminants for the toxicity characteristic identified in Part 261, Section 24, Table 1. There are no maximum concentrations listed in Table 1 for the toxicity characteristic for copper and nickel. However, the TCLP analysis shows that copper and nickel have only a small potential to leach from the waste. Photo Stencil has indicated that all delisted sludge will be disposed in a compliant Subtitle D solid waste landfill. Disposal in a solid waste landfill will ensure protection of human health and the environment from any metals contained in leachate that might migrate from the waste.
Further, the results of the waste sampling indicated that the wastewater treatment sludge does not contain any organic constituents. Consideration of the potential health effects caused by exposure to organic constituents was therefore not considered in evaluating the petition by the Division.
This delisting is being granted under conditions that specify disposal, record keeping, and storage requirements for the delisted sludge. Conditional delisting of the waste also prohibits any major changes to the electroplating and chemical etching or wastewater treatment process without prior notification, evaluation, and approval by the Division.
This delisting does not apply to waste that demonstrates "significant changes" as defined in Delisting #006 in Part 261, Appendix IX--Wastes Excluded Under § 260.20 and § 260.22(d), or if any of the conditions specified in Part 261, Appendix IX for this delisting are not met. Should either of these occur, the waste is and must be managed as a hazardous waste.
Statement of Basis and Purpose - Rulemaking Hearing of July 20, 2004
6 CCR 1007-3-8.52