HAZARDOUS MATERIALS
STANDARD OF REVIEW
According to the CBJ Mining Ordinance (49.65.135(a)), the CBJ shall require that:
(2) . . .
(3) Hazardous and toxic materials . . . be properly contained and disposed of in accordance with applicable federal, state and city and borough laws, rules and regulations;
(4) The operator conduct all mining operations ...so as to minimize to the extent reasonably practicable safety hazards and to control and mitigate adverse impacts on the public and neighboring properties . . ."
Policy 3.13 of the CBJ Comprehensive Plan (1996) states:
Policies of the Juneau Coastal Management Program state:
"Shoreline industrial developments, ports, harbors and marinas shall be sited, designed, constructed and operated such that . . . [f]acilities for proper handling of ... fuel and waste oil are provided." (CBJ 49.70.905(5)(B))
This staff report analyzes the potential impacts from hazardous and toxic materials associated with the Kensington mine project, proposed measures to contain and dispose of hazardous and toxic materials, proposed means to minimize safety hazards associated with hazardous and toxic materials, and measures to control and to mitigate adverse impacts on the public and neighboring properties.
BACKGROUND
Regulatory Framework. Regulation of hazardous materials and wastes involves a number of state and federal regulations. Which regulations apply, and which agencies are involved, depend on the amount and nature of the substance; whether the substance is being transported, stored, treated or disposed of; and whether transportation occurs by air, land or water. Some of the requirements that will apply (to name a few) include:
The state and federal regulatory framework is thorough and complex.
ANALYSIS
Chemical Inventory. The Kensington Gold Project will involve the use of a number of chemical substances. The following list is compiled from the Final EIS (1992), Coeur's Amended Plan of Operations (August 1997), and the Final SEIS (1997):
Milling Reagents and Chemicals
Batch Plant
Fuels
Maintenance Chemicals
Drinking Water Treatment Chemicals
Mill Tails
Wastewater Treatment
Laboratory Chemicals
Explosives
Hazardous Wastes
Chemical Characteristics. Most of the identified substances have widely understood properties. Diesel and aviation fuels pose well-known fire hazards. Polymers are long-chained carbon compounds used in water and wastewater treatment. Ferric chloride is a common additive in drinking water treatment. Explosives pose obvious hazards, but are strictly controlled. Some of the less familiar substances that will be transported to, and used at the operation include methyl isobutyl carbinol (MIBC), lead nitrate and hydrogen sulfide.
MIBC is a colorless liquid with a mild odor. The U.S. Department of Transportation classifies it as a moderately (Class II) combustible liquid (N.I.O.S.H., 1994). It is a skin and eye irritant, and can be inhaled or absorbed through skin and damage the central nervous system. There are limits on the concentrations to which workers can be exposed (NJ, 1997).
Lead nitrate is a solid that is poisonous on ingestion or inhalation of dust. It is a skin and eye irritant, and long-term or repeated high exposure can cause a number of chronic effects associated with lead poisoning such as nerve damage, kidney and brain damage, and anemia. There are limits on the concentrations of the lead in lead nitrate to which workers can be exposed (NJ, 1997).
Hydrogen sulfide is a colorless, poisonous gas with a strong odor of rotten eggs. It can attack eyes, lung tissues and the central nervous system. It is shipped as a compressed gas, and is listed as an Extremely Hazardous Substance -- or a substance that poses an acute inhalable toxic threat -- by the EPA (EPA/FEMA/DOT, 1987).
With the exception of hydrogen sulfide, none of the chemicals specifically identified for use in substantial quantities are listed by EPA as Extremely Hazardous Substances. Nor are any of the other chemicals compressed gases which can undergo rapid release without the assistance of a chemical reaction, such as a fire. Hydrogen sulfide is a more dangerous chemical (from the standpoint of toxic inhalation threat), but it is routinely used in wastewater treatment, and subject to strict industry standards, code and regulatory requirements. It is not as toxic, for example, as chlorine gas which is used by the city and borough for water treatment. Chemicals not specifically identified, such as those for laboratory or maintenance use, will be transported and used in small quantities that do not pose significant threats.
Standard methods are available for estimating the likelihood of a release of a hazardous substance. Statistics suggest a greater likelihood of a significant release occurring during transportation or long-term warehousing of substances than during short-term storage or use. On the other hand, short-term storage and use results in more frequent, but smaller spills (EPA/FEMA/DOT, 1989). The Final SEIS reviews the results of modeling efforts to predict the likelihood of spills during on-site and off-site transportation.
On-Site Transportation. The Final SEIS suggests that the risk of a release of the entire 5,000 gallons of diesel fuel from a tanker truck on the haul road is about 1 in 900 each year. The risk of release of the entire contents of a container with one ton of lead nitrate is estimated at about one in one million each year. The probability of a large spill of tailings from the pipeline is estimated at about 1 in 700 each year with a total risk over the life of the mine of about 1 in 50. The maximum spill would result in release of the entire pipeline volume of about 270,000 gallons. Risks would be mitigated by using a double-walled pipe and through use of leak detection sensors. The potential impacts on human health and the environment are a function of the location of the release (USFS, 1997c).
Off-Site Transportation. Hazardous and toxic materials would be delivered to the site by barge. Under the SEIS preferred alternative, 6.5 million gallons of diesel fuel will be consumed each year, requiring regular barge shipments and fuel transfer operations. Hazardous materials would also be included among the 700 to 800 tons of freight shipped to the site each month.
Based on records showing no oil spills due to fuel barge sinkings or damage in Lynn Canal since 1986, the SEIS concludes that the risk associated with barge transport of fuel to the Kensington Gold Project "is minimal" (USFS, 1997). The 6.5 million gallons of fuel required by the Kensington mine is a relatively small percentage of the total 42.5 million gallons of fuel transported annually to Haines and Skagway. Staff suggests that while there is always risk -- particularly to the environment -- associated with water transport of fuels, that the risk associated with this particular project is small in relation to the overall risk of fuel transport via Lynn Canal.
The Final SEIS predicts a 1 in 10 chance of an oil spill during barge-to-shore transfer operations, with a cumulative risk of 1 to 2 spills over the life of the mine project. The maximum spill size is estimated to be about 880 gallons. At that frequency and size, no significant, long-term impacts are expected.
On-site Storage and Use. Fuel, wastes and other substances will be stored in a number of locations at the project site. Milling reagents and hazardous wastes will be stored in compliance with regulations pertaining to containers, labeling, and other spill prevention and safety matters. A total of about 1.2 million gallons of diesel fuel will be stored at the site. According to the Final SEIS, "...one 300,000-gallon tank would be located near Comet Beach, and one 300,000-gallon tank would be located at the laydown area. At the process area, two 20,000-gallon tanks would be located at the 800 foot portal and two 300,000-gallon tanks would be located adjacent to the generators." Helicopter fuel will be stored in 5,000-gallon ISO containers within the secondary containment area for the 300,000-gallon diesel tank. All fuel storage will include secondary containment, and fuel storage in the Comet Beach area will include tertiary containment (Hopson, 1997; Montgomery Watson, 1997b).
In discussions with other agencies, ADEC suggests that "...the primary risk is from an oil spill during a marine transfer during a gillnet opening, which would foul boats and nets and close the fishery." Staff concur, and add that all available evidence suggests that marine fuel transfer likely represents the greatest risk of release of all the hazardous substances. In response to ADEC comments on the applicant's discharge prevention and contingency plan (Hopson 1997b), Coeur has included specific measures to guard against a release during a gillnet opening, and to provide immediate response should such a release occur. The fuel transfer procedures (Section 2.1.5 of the Kensington Oil Discharge Preventive & Contingency Plan) now specify "...[t]o the greatest extent practicable, fuel deliveries will be scheduled to occur on days when the local gillnet fishery is closed" (Montgomery Watson, 1997a). The Lynn Canal commercial gillnet fishery opens on Sundays and typically operates 2 to 3 consecutive days per week from the third week in June through late September. The wording of this requirement takes into account that Coeur will not have complete control over the fuel delivery schedule, and that some deliveries during gillnet openings will be unavoidable. In such case, the contingency plan specifies that response equipment be readied for deployment prior to fuel delivery. This includes providing additional personnel, readying the skiff, and faking out containment boom with tow bridle and anchor systems made up for immediate deployment. With only one fuel barge per week (on average during the year) and several days of fishery closure during each week of the 4-month fishery, it appears that this response readiness requirement would probably not be invoked frequently. Staff conclude that these are reasonable measures to control risks and potential impacts.
Summary. Methods for transporting, handling, using, and storing all of the identified hazardous substances are carefully regulated to safeguard worker and public health. Due to the nature of the substances and the applicant's plans to comply with extensive applicable state and federal law, staff believe that the hazardous and toxic chemicals associated with proposed operations will be contained and disposed of in accordance with applicable statutes, rules, and regulations.
Discussion of SEIS Alternatives. Eliminating the use of sodium cyanide and chlorine by eliminating the on-site carbon-in-leach (CIL) ore processing significantly reduces potential hazards associated with accidental releases. The U.S. Forest Service's preferred alternative (Alternative D) and the applicant's original proposal (Alternative B) differ in the likelihood and size of a tailings spill. The SEIS indicates that under the applicant's proposal, there is about a 1 in 80 chance of a spill of 50 tons of de-watered tailings in any year. Under the U.S. Forest Service's preferred alternative, there is about a 1 in 700 chance of a 270,000-gallon tailings slurry spill in any year.
STAFF FINDINGS
Yes.
2. Will toxic and hazardous substances associated with the proposed mine project endanger the public health or safety? (CBJ 49.15.330(f)(1))
No. Use of standard models predicts a low frequency of releases of toxic and hazardous substances. Spills that are more likely to occur would be small. Only one of the substances is considered an Extremely Hazardous Substance, and it (hydrogen sulfide) is a widely used wastewater treatment chemical with well-established and effective handling safeguards.
3. What will be the effect of toxic and hazardous substances on the value of property in the neighboring area? Will transportation, use, storage, accidental release, or disposal of toxic or hazardous substances be out of harmony with property in the neighboring areas?
(CBJ 49.15.330(f)(2))
Except in the event of a major, accidental release, the presence of toxic and hazardous substances will have no effect on neighboring areas. The likelihood of a major release is small. Any effects of smaller releases will be short-lived.
4. Will the proposed mine project be in general conformity with the comprehensive plan, thoroughfare plan, and other officially adopted plans as they may apply to hazardous materials? (CBJ 49.15.330(f)(3))
Yes. The project, as proposed, conforms with Policy 3.13 of the CBJ Comprehensive Plan which addresses the mitigation of impacts associated with hazardous materials. Proper handling of mining and water treatment chemicals, fuels and other hazardous materials will minimize the likelihood of a sizable spill.
5. Will hazardous and toxic materials be properly contained and disposed of in accordance with federal, state, and CBJ laws, rules, and regulations? (CBJ 49.65.135(a)(2))
Yes. The applicant's proposal includes plans for transportation, storage, use and disposal of hazardous materials. Plans comply with all applicable codes, standards and other regulations.
6. Will operations involving hazardous and toxic substances be conducted to minimize safety hazards and to control and mitigate adverse impacts? (CBJ 49.65.135(a)(3))
Yes. The applicant's proposal includes plans for preventing as well as responding to accidental spills. Any spills that occur are not likely to have significant or long-term impacts.
7. Will hazardous materials be stored within one-hundred-year floodplains?
(CBJ 49.70.910(j))
No. The application does not propose storage of hazardous materials within 100-year
flood plains.
8. Will facilities for proper handling of fuel and waste oil be provided? (CBJ 49.70.905(5)(B))
Yes. Appropriate facilities for fuel transfer and storage are included in the applicant's discharge prevention and contingency plan. Waste oil will be collected and burned at the project site to provide secondary heat in approved used oil heaters or disposed of by an approved used oil contractor.
STAFF RECOMMENDATION
Staff recommends approval of this aspect of the project.
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