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Treatment of Energetic Wastes by Open Detonation at China Lake. Laurie Zellmer * Thomas Boggs Therese Atienzamoore Brenda Abernathy Eric Erickson Robin Nissan Roxanne Quintana Andrew Chafin . 30th Environmental & Energy Symposium San Diego, CA April 5 - 8, 2004.
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Treatment of Energetic Wastes by Open Detonation at China Lake Laurie Zellmer * Thomas Boggs Therese Atienzamoore Brenda Abernathy Eric Erickson Robin Nissan Roxanne Quintana Andrew Chafin 30th Environmental & Energy Symposium San Diego, CA April 5 - 8, 2004
Participating Organizations • NAWCWD China Lake • NAWS China Lake • Chemical Compliance Systems, Inc. • URS Corporation • W. Mitchell and Associates
Main Topics • China Lake and its OD Facility • Permitting and the Original Health Risk Assessment (HRA) • Efforts to Rework the HRA • 1) Emissions Factors Database • 2) Fate of Metals • 3) Simulated OD Tests of Energetic-Contaminated Wastes • Other HRA Requirements
China Lake • Located in Upper Mojave Desert • - Arid climate • - >330 clear days per year • Navy’s largest Research, Development, Test, & Evaluation (RDT&E) facility • - Land (orange):1,100,000 acres or 1700 square miles • - Airspace (blue): 12,500,000 acres or 19,600 square miles • Minimal Encroachment • - Little population growth • - Mainly surrounded by BLM land
China Lake Mission • RDT&E of weapons systems, software integration, and energetic materials • In performing mission... • Generate 100,000 to 300,000 pounds of energetic waste per year • - Cannot transport off-CL • - Must treat on-site
Energetic Wastestreams Generated • Munitions • - Expired/Excessed (Standard Items) • - RDT&E (NonStandard Items) • Laboratory R&D • - Leftover scrap from mixes/casting • - Energetic-contaminated “trash” (e.g. rags, gloves) • - Samples • - Contaminated solvents
Current Method of Treatment • Open Detonation - Primary method of treatment • Rarely Open Burn; Last OB Aug 98 • OD directly on ground (Waste is NOT buried) • Range Limit = 15,000 lbs Explosive Weight
View of OD Facility (One Mile to South & 700 Feet Above) Arid & Mountainous Depth to Groundwater is > 400 feet 1400 Feet Above OD Facility
China Lake’s North Range Prevailing Wind
Permitting for China Lake OD Facility • Currently operates under: • - RCRA (Hazardous Waste) Part A Interim Status Permit • - Clean Air Act Title V Permit • Permitting Requirements • - Numerous! • - Human Health Risk Assessment (HRA) • HRA Addresses: • - Lifetime risk of developing cancer • - Potential for chronic non-carcinogenic effects • - Potential for acute non-carcinogenic effects • Preparation of original HRA started in early 1990s with direction from CA EPA
Original HRA Lack of Validated Data in early 1990s + Lack of Standardized Guidance Use of Overly Conservative Assumptions Inaccurately Inflated Health Risks Severe Limitations in Annual & Event Treatment Amounts
Contd - Original HRA Conflict with Safety Standards & Environmental Regulations Safety Standards for OD Activities emphasize… “Avoid Excessive Unpacking of Waste Items” Increased handling Increases probability of incident (injury/death) Example… Leftover energetic mix placed inside a velostat bag which is placed inside a bucket… Unpacking = Removal of the bucket To comply with inflated health risk limitations… Forced to Unpack Waste Items Unacceptable! … Rework Original HRA
Revisions to the Original HRA • With expertise from our technical codes, initiated four major efforts • 1) Emissions Factor Database • 2) Fate of Metals (especially from casings) • 3) Simulated OD Tests for Explosive-Contaminated Wastes • 4) Alternative Technology Assessment (will not be discussed, but copies are available) • Our New Approach • - Science-based • - Technically accurate • - Data-driven • - Regulatory agencies support!
EFFORT #1: Emission Factor Database • Very difficult to collect emission data from actual OD events - Extreme violence of the detonation prevents monitoring emissions at the source - Entrained dirt in the detonation plume prevents remote monitoring with optical methods until dust dissipated • Turned to detonation tests in controlled environments for EF data - Bang Box - OBODi - Fly-through tests at DPG - Nevada Test Site
Contd - EFFORT #1: Emission Factor Database Huge Matrix of EF Data EF Data from Over 100 Tests ~1000 Compounds
Contd - EFFORT #1: Emission Factor Database List of ~1000 compounds 1) California Assembly Bill 2588, Air Toxic “Hot Spots” Information & Assessment Act (AB2588) - Compounds of health concern 2) EPA Region IX Preliminary Remediation Goals (PRGs) - Compounds of health concern 3) China Lake 1996 original HRA 4) Compounds from tests Huge matrix— How can we simplify?
Contd - EFFORT #1: Emission Factor Database Step 1 - Eliminate Compounds ~1000 compounds • Duplicates • Pesticides / herbicides • Pharmaceuticals • Compounds with elements not in parent energetics (e.g. Sb, Se) • ~600 compounds remain • ~400 of these are of health risk concern (i.e. on the AB2588 and/or PRG lists)
Contd - EFFORT #1: Emission Factor Database Step 2 - Combine tests into Energetic Families with like emissions Explosives Propellants Miscellaneous
Contd - EFFORT #1: Emission Factor Database Step 3 - Place each compound into 1 of 4 Quadrants Health Concern 2 1 2-Chloropropane Benzene No Data Data Graphite Carbon Dioxide 4 3 No Health Concern
Contd - EFFORT #1: Emission Factor Database Quadrant 2How perform HRA for ~250 compounds that are of a health concern but without data? First conducted a “Health Risk Screening”… 1) Couple the likely concentrations of ALL Quadrant 2 compounds with their toxicities 2) Then rank the compounds to identify the compounds that contribute the most health risk 3) Focus on those compounds that contribute to the top 90% of health risks ~25 Compounds
Contd - EFFORT #1: Emission Factor Database Quadrant 2 Second, identified emission factors on a family basis… No Can it be formed by this family? Ignore for this family Yes No Is it in the top 90% health risk? Ignore Yes No Surrogate EF: Similar compound in same family? Surrogate EF: Similar compound, similar family? Yes No Yes SWAG: CHEETAH, math treatment of other family, etc. Use for EF in HRA
Contd - EFFORT #1: Emission Factor Database TNT (A1) Family - Quadrant 2(With Health Concern but No Data) No Can it be formed by this family? Ignore for this family 2-Chloropropane Yes No Is it in the top 90% health risk? Ignore Yes No Surrogate EF: Similar compound in TNT family? Surrogate EF: Similar compound, similar family? Yes No Yes SWAG: CHEETAH, math treatment of other family, etc. Use for EF in HRA
Contd - EFFORT #1: Emission Factor Database TNT (A1) Family - Quadrant 2(With Health Concern but No Data) No Can it be formed by this family? Ignore for this family Yes No Is it in the top 90% health risk? Ignore m-Xylene Yes No Surrogate EF: Similar compound in TNT family? Surrogate EF: Similar compound, similar family? Yes No Yes SWAG: CHEETAH, math treatment of other family, etc. Use for EF in HRA
Contd - EFFORT #1: Emission Factor Database TNT (A1) Family - Quadrant 2(With Health Concern but No Data) No Can it be formed by this family? Ignore for this family Yes No Is it in the top 90% health risk? Ignore Yes No Surrogate EF: Similar compound in TNT family? Surrogate EF: Similar compound, similar family? Yes No Nitropropane Yes Use nitromethane for EF in HRA SWAG: CHEETAH, math treatment of other family, etc.
Contd - EFFORT #1: Emission Factor Database Summary • Identified gaps in the test data • Simplified management of the database • Developed logical approach to identify surrogate compounds where data lacks but a health concern exists (Quadrant 2) - These compounds are commonly ignored!
EFFORT #2: Fate of Metals in Munitions • Original HRA assumed that metal casings vaporize completely • Major driver of acute and chronic noncancer risks • Metal Casings are Designed to Fragment, • NOT Vaporize
Contd - EFFORT #2: Fate of Metals • Three Types of Metals in Munitions • 1) Additives in Energetics • - Participate in detonation reaction to form metal oxides • - To increase performance & modify burn rate (e.g. Aluminum) • - Included in emission factor database (Effort #1) • 2) Paints/Coatings • - Very low concentrations • 3) Casings • - No chemical reaction; Break apart
Contd - EFFORT #2: Fate of Metals Proof that Metals Casings Fragment 1) Test Data - Lethality studies of weapons where 95 - 99% metal recovered as fragments
Contd - EFFORT #2: Fate of Metals Proof that Metals Casings Fragment 2) Fragments from OD site - Sharp edges; No evidence of melting Heavy or light case, steel or aluminum - No signs of melting Without melting… No vaporization!
Shows initial case deformation/fracture • Gases escaping • Case fragmentation Contd - EFFORT #2: Fate of Metals Proof that Metals Casings Fragment 3) High Speed Photos (1 million frames/second) - Shows weapons fragmenting
Contd - EFFORT #2: Fate of Metals Proof that Metals Casings Fragment 4) Heat Transfer Calculations Prove that OD temperatures are not hot enough to melt or vaporize the casing Without melting… No vaporization!
Contd - EFFORT #2: Fate of Metals Proof that Metals Casings Fragment 5) Metallurgical Analysis of OD Fragment Prove that OD temperatures are not hot enough to melt or vaporize the casing Thin feathery edge most susceptible to melting; Edge is not featureless Rolled edge shows evidence of mechanical deformation, not intense heat
Contd - EFFORT #2: Fate of Metals • FACT: Evidence that casings do not vaporize is overwhelming, but need to…. • Refine analysis to account for casing particulates • Combine the amount of metal in the casing with available emissions test data • Example: Consider a steel rocket motor casing that contains Mn • (0.4 lbs of steel / lb of energetic) x • (0.006 lbs Mn / lb of steel) x • (0.000067 lbs Mn emitted / lb Mn in steel) • =1.61E-7 lbs Mn emitted / lb of energetic
Contd - EFFORT #2: Fate of Metals • SUMMARY • Calculations indicate that EFs for metal casings are FOUR orders of magnitude lower than the original HRA • Chromium, Nickel, & Molybdenum were not considered in original HRA, but are in the revised methodology
EFFORT #3: OD Tests for • Energetic-Contaminated Waste (ECW) • ECW = Rags, gloves, plastic, aluminum foil, etc. contaminated with energetics • Fuel-rich materials • - Unlike energetics… stoichiometric • mixtures of fuel & oxidizer • Combustion of fuel-rich materials can generate toxic emissions (e.g. dioxins) Incinerators • No emission factor test data for OD of ECW • Small-scale chamber tests conducted at China Lake
Contd - EFFORT #3: OD Tests for ECW 3 TESTS Detonator: RP-501 Donor: 225 g Comp A-3
Contd - EFFORT #3: OD Tests for ECW • 3 TESTS • Detonator: RP-501 • Donor: 225 g Comp A-3 • Propellant: 140 g AP • ECW Sample: • 11.0 g Plastic • 1.2 g Al Foil • 0.4 g Glass • 32.5 g Paper & Rags • 5 g Acetone
Contd - EFFORT #3: OD Tests for ECW • Tests designed to maximize dioxin formation • Used AP-based energetic: • - High fuel content • - High chlorine content • Representative of wastes treated at China Lake As-Cast ECW & AP Mix
Contd - EFFORT #3: OD Tests for ECW ECW Dioxin Emission Factors Three orders of magnitude lower than original HRA which used a medical waste incinerator model!
Contd - EFFORT #3: OD Tests for ECW SUMMARY • Within experimental error, all carbon from the ECW is present as CO and CO2 - Proves that reaction (afterburning) is complete • Except for dioxins, treatment of ECW by OD is cleaner than the Comp A-3 donor - Likely an artifact of higher temperatures from the AP propellant • The primary driver for health risks (i.e. dioxins) is significantly lower than predicted in the original HRA (medical waste incinerator model)
Other HRA Requirements • Emissions from Munition Components • Circuitry found in the guidance & control sections • Very difficult to determine accurately • Will add a small percent (to be negotiated) to the emissions for the ECW family
Contd - Other HRA Requirements • Dust Emissions from the OD Crater • Measure volume of craters • Plot Crater Volume vs Explosive Wt • For PM10 and PM2.5 emissions, analyze ash samples for particle size distribution • For toxic compounds, use actual soil sample data
Contd - Other HRA Requirements • Windblown Dust • Use 39 acres… includes sides of canyon & disturbed area • For PM10 and PM2.5 emissions, use 1985 EPA document • “Rapid Assessment of Exposure to Particulate Emissions from Surface Contamination Sites” • For toxic compounds, use actual soil sample data • Dust from Grading • Use 5.5 acres of disturbed area • For PM10 and PM2.5 emissions, use EPA AP-42 EFs for heavy construction • For toxic compounds use actual soil sample data
Contd - Other HRA Requirements • Reaction Volume • EFs divided by the reaction volume = Concentration of species at ground zero • For simplicity use visual measurements of the dust cloud Actual Visual Actual reaction volume is larger; Reaction gases are invisible Larger reaction volume produces lower concentrations!
Contd - Other HRA Requirements • Dispersion Models • Upper level mushroom cloud & stem of OD plume • Open Burn/Open Detonation Dispersion Model (OBODm) • Lower level of OD plume including dust entrainment • Industrial Source Complex Short-Term (Version 3) (ISCST3) • Meteorological Data • Use 4 years of sequential hourly data • Met station located 1 mile south & 700 feet above the facility
Contd - Other HRA Requirements • Receptors • Use fenceline receptors every • 22.5 degrees • Also occupational, residential, & sensitive receptors on- and off-China Lake property China Lake North Range Occupational School Day Care Hospital
Contd - Other HRA Requirements • Toxicity Values • Only for Quadrants 1 and 2 compounds • Use published toxicity values from five sources in a priority manner • Use surrogate compounds where no values exist • Health Effects • One in a million cancer risk • Hazard index = 1 for chronic & acute non-cancer effects
Contd - Other HRA Requirements • Exposure Routes • Inhalation, ingestion, dermal contact with soil, human milk ingestion by infants • Health Risk Calculations • Oct 03 CAPCOA Air Toxics “Hot Spots” (AB2588) Program Guidance Manual for Preparation of Health Risk Assessments
Conclusions • China Lake has developed an innovative, science-based approach to address potential impacts on human health from OD activities • Reworking of the original HRA lowers health risks by several orders of magnitude • Because of the site’s location and method of operation, OD can be environmentally friendly, especially at a facility like China Lake’s