DASIC ECOSAFE OSD

1. Maximum storage temperature (e.g., ^oF and/or ^oC): 170^oF
2. Minimum storage temperature (e.g., ^oF and/or ^oC): -30^oF
3. Optimum storage temperature (e.g., ^oF and/or ^oC): 40^oF to 100^oF
4. Humidity (e.g., g/kg): External humidity can range from 0-100% if containers are maintained with a nitrogen blanket. Containers stored in humidity >60% may experience corrosion. Prolonged storage of containers in high humidity environments (>60%) require frequent inspection (monthly) to ensure their integrity.
   • Maximum humidity: 100%
   • Minimum humidity: 0%
   • Optimal humidity: 0-60%
5. Other relevant conditions for product storage: Protect from exposure to direct sunlight. Exposing Dasic EcoSafe OSD will cause rapid degradation, however, storing in proper containers prevents this. Containers themselves are subject to UV degradation; and should be protected from long-term exposure to direct sunlight as well.
6. Description of the consequences to performance if product is not stored within these limits: The primary concern with storage of Dasic EcoSafe OSD outside the optimum ranges described above for long periods (over 6 months) is degradation and/or precipitation of one or more components of the product. This could impact product effectiveness. Storage of the product outside the maximum and minimum ranges described above for short periods (48 hours) is likely to have little impact on product effectiveness. If Dasic EcoSafe OSD is stored outside the optimal ranges of temperature and humidity but within the maximum and minimum ranges for >6 months, it is recommended that a Dasic USA, LLC representative perform an evaluation of the product in each container stored outside the optimal ranges and either recertify its quality or replace it. Storage of containers in direct sunlight or in humid environments (>60% humidity) for long periods (>6 months) can result in degradation/corrosion of the container itself. This can result in cracking and eventual failure. A minimum of biannual inspection of all Dasic EcoSafe OSD storage containers is recommended with monthly inspections being ideal. If failure of individual containers is identified (i.e., discoloration, cracking, leaking, excessive warping), it is recommended that a Dasic USA, LLC representative repackage the product and recertify the product integrity.

(7) SHELF LIFE STORAGE CONDITIONS [§ 300.915(a)(7)]

(9) PRODUCT CATEGORY AND PROCESSES [300.915(a)(9)]

Dasic EcoSafe OSD submitted as a chemical agent under the dispersant category.

The specific process through which the product affects the oil is as follows: Dasic EcoSafe OSD contains a mixture of surfactants in a carrier solvent. It is sprayed onto the surface of an oil floating on a marine environment or directly into a jet of oil escaping to a marine environment from a subsea release point. Once the product contacts the oil, the surfactants in Dasic EcoSafe OSD rapidly locate to the interface between the oil and the water for a subsea oil release or both the air/oil and oil/water interfaces for an oil floating on a marine surface. Once the surfactants reach these interfaces, they change the surface and/or interfacial tension of the oil. This allows the oil to break into droplets that are so small they are essentially neutrally buoyant when Dasic EcoSafe OSD is applied to an oil floating on a marine surface, or it reduces the size of oil droplets resulting from a subsea release by at least an order of magnitude.

The surfactants in Dasic EcoSafe OSD not only reduce the oil’s surface/interfacial tension, they also protect the droplets from recoalescence once they are formed. This is important because initially plumes of oil formed after treating oil with Dasic EcoSafe OSD are very concentrated in droplets and because of this they tend to frequently collide with each other. Dasic EcoSafe OSD significantly reduces the efficiency of coalescence resulting from these collisions. Without application of Dasic EcoSafe OSD, oil emanating from a subsea release or oil on a marine surface that is impacted by breaking waves will form small droplets initially, but they can rapidly recoalesce to form large droplets that rapidly resurface or reach the surface.

Note that dispersed oil droplets are positively buoyant until they undergo significant biodegradation. "Essentially neutrally buoyant" means that the droplets become so small that their rise velocity is low enough that they are under the influence of ocean currents and turbulence for long periods. Thus, if they do resurface at some point, they are dispersed widely enough to only form very thin sheens on the surface that are themselves subject to rapid redispersion into the water column after they encounter mixing energy from waves. In contrast, large oil droplets can rapidly resurface in a location with other droplets to reform a thick slick that can weather and emulsify to become persistent. Thin sheens aren't thick enough or persistent enough to form emulsions as they tend to rapidly redisperse in most offshore wave environments.

Applying Dasic EcoSafe OSD to a jet of oil emanating from a subsea release reduces the interfacial tension of the oil in the same way as for a surface oil. The exact size of the resulting droplets depends on the amount of turbulent energy in the jet of oil and properties of the oil itself. It is expected that Dasic EcoSafe OSD will reduce the interfacial tension of oil from subsea releases enough to produce oil droplets that are at least an order of magnitude smaller than they would be without treatment. The benefits, at a minimum, will be a hundred-fold reduction in the average rise velocity of droplets emanating from a subsea release because the rise velocity of oil droplets is approximately directly proportional to the square of the oil droplet radius.

Oil droplets that remain entrained in the water column will be rapidly diluted to concentrations low enough to allow aerobic biodegradation of individual oil droplets by petroleum degrading microorganism without exhausting the nutrients or oxygen available in most open marine environments. Individual droplets are rapidly colonized by petroleum degrading microorganisms once they enter the water column. Half-lives of the oil is expected to be on the order of 2-4 weeks. In addition, petroleum-degrading organisms degrade the most soluble petroleum compounds first and fastest. Many of these compounds tend to be the more toxic components of crude and fuel oils. This results in the oil droplets becoming less toxic as biodegradation continues. Ultimately, biodegradation produces a residue that consists of large insoluble compounds that are recalcitrant and not bioavailable.

Reducing the diameter of the average droplet emanating from a subsea release by an order of magnitude could have the same effect as applying Dasic EcoSafe OSD to a surface oil if the turbulent energy of the release jet is high enough. At a minimum, however, reducing the diameter of oil droplets by an order of magnitude will reduce the rise velocity of these droplets by two orders of magnitude thereby allowing the droplets to remain in the water column for significantly longer period – from maybe just a few hours to many tens of hours. This allows the droplets to drift with ocean currents for longer periods and likely surface large distances from the release point thereby protecting responders tasked with stopping the flow of oil from being inundated by volatiles. Relatively fresh oil surfacing from a subsea release will contain volatile components that will rapidly transfer to the air and potentially produce a hazardous environment for responders. Thus, in many scenarios, application of Dasic EcoSafe OSD to a jet of oil emanating from a subsea release will protect the safety of responders attempting to control the oil flow.

1. Application Method:
   • Aerial application: Application altitudes exceeding 200 feet are acceptable under certain conditions. Spray nozzle location, spray pressures/flowrates, and nozzle opening diameter are all critical to achieving the desired dosage and droplet size. Design of these aspects of an aerial delivery system all depend on the aerial platform used and the application conditions (e.g., application altitude and speed). Parameters for this equipment cannot be prescribed because of the variability of the aerial delivery platforms used by oil spill response organizations (i.e., they vary from helicopters to 737 aircraft). It is recommended that organizations responsible for aerial dispersant spray operations base the appropriate nozzle configuration, delivery pressure/flowrates, spray altitude, and delivery speed on model predictions using prediction tools such as the BSEE Aerial Dispersant Application Decision Support Tool. This tool uses the specification of the aerial delivery system, the aerial delivery platform, and characteristics of Dasic EcoSafe OSD (e.g., droplet density and size distribution) to predict the mass deposition density of dispersant. This type of model allows completion of a multi-variate analysis of aerial spray systems for specific aerial spray platforms to maximize the dispersant delivery accuracy (i.e., onto floating oil) while maximizing application altitude to increase the safety of crews in aerial delivery aircraft.
   • Boat application: Dasic EcoSafe OSD may be applied by boats equipped with spray equipment (e.g., spray systems mounted in a way to apply the dispersant before the boat bow wave pushes the oil away from the spray or specialized spray equipment. Natural wave or boat wake action provides adequate mixing energy to disperse the oil. As with aerial spray delivery systems, operators of boat-based delivery systems need to calibrate their systems to allow the highest efficiency delivery of Dasic EcoSafe OSD to floating oil.
   • Subsea application: Dasic EcoSafe OSD may be applied to a subsea well blowout using boats that maintain a supply of the product, appropriate pumps, and appropriate conduits from the boats to the location of the subsea release at the seabed. A simple wand-based system placed as near the release point as possible is recommended to deliver Dasic EcoSafe OSD into the oil jet. Nozzles on these wands can be any of several diameters that allow Dasic EcoSafe OSD to efficiently pass into the oil jet without passing through it. Several organizations have subsea dispersant injection systems that can deliver Dasic EcoSafe OSD.
2. Concentration / Application Rate: Dasic EcoSafe OSD is best applied undiluted. Diluted application can be attempted if application equipment requires higher flow rates. Diluted application may be effective given the appropriate oil and spill conditions. As with any dispersant use, field-based dispersant monitoring should determine if the application is successful. Dasic EcoSafe OSD is applied as high as 1 part dispersant to 10 parts oil to as low as 1 part dispersant to 100 parts oil. The exact ratio depends on many factors during a spill response such as the oil type, the amount of oil weathering/emulsification, the type of spill, and the weather or release conditions.
   • For surface application: It is recommended applying Dasic EcoSafe OSD at treatment rates of between 2-10 U.S. gallons per acre to oil floating on the surface. Lower rates are suitable for readily dispersible oils and higher rates or reapplication may be needed for more challenging oils.
   • For subsea application: Treatment rates of 1 part dispersant to 100 parts oil or even lower are recommended. These lower treatment rates are possible for subsea application because oils emanating from a release point are fresh and likely significantly more dispersible than the same oil that may have weathered and emulsified on a marine surface for hours to days before treatment. Treatment ratios lower than 1:100 might be used for highly energetic subsea release scenarios that are expected to produce smaller dispersed oil droplets. Actual treatment ratios and rates of Dasic EcoSafe OSD during an actual spill depends on many factors, however, in all cases treatment ratios should be based on field dispersant effectiveness monitoring such as the Special Monitoring of Applied Response Technologies. For subsea dispersant use, a monitoring protocol to assess dispersant effectiveness such as the "Environmental Monitoring for Atypical Dispersant Operations" developed by the US National Response Team is recommended.
3. Conditions for Use:
   • Surface oil: Dasic EcoSafe OSD is designed for use in a wide range of surface application conditions from tropical, to temperate, to subarctic, and arctic temperature conditions. Use of Dasic EcoSafe OSD in zero or subzero air temperatures is possible, but it is recommended that the product be stored in containers that maintain temperatures above 40^oF to ensure suitable flow characteristics before delivery. In addition, Dasic EcoSafe OSD is designed to be applied through a broad range of wind and wave conditions from flat calm to Beaufort 6 and beyond. The maximum wind/wave conditions will depend on the safety of the crew during delivery operations. Dasic EcoSafe OSD can be applied in flat calm or near flat calm conditions (non-breaking waves) as well. Application in non-breaking wave conditions may not result in immediate dispersion as would occur in breaking wave conditions so monitoring should account for this. In non-breaking waves, effective application of Dasic EcoSafe OSD will force the oil to spread very thin if the oil is in an open water environment. As the oil thins, it will become easier to disperse even in low-energy waves. Monitoring the effectiveness of Dasic EcoSafe OSD for up to 24 hours is recommended in non-breaking waves.
   • Subsea oil releases: Dasic EcoSafe OSD is designed to be effective in deepwater subsea salinity and temperature conditions (40^oF and 35 ppt salinity). Higher temperatures are not a problem. Salinities significantly above 35 ppt require field-based monitoring to assess effectiveness (e.g., with the Environmental Monitoring for Atypical Dispersant Operations protocol).
   • Water salinity: Dasic EcoSafe OSD can work in low salinity environments (e.g., as low as 20 ppt or even lower and up to 35 ppt and higher). The effectiveness of the product in low salinity (below 20 ppt) and high salinity (well above 35 ppt) will depend on the oil and spill conditions. As with any dispersant operation, a field-based monitoring protocol should be used to assess effectiveness of Dasic EcoSafe OSD in conditions of either low or high salinity.
   • Types and weathering states for oils: Dasic EcoSafe OSD was developed to treat a broad range of oils from low viscosity fresh oils to highly weathered and emulsified viscous oils. Specific ranges of oil weathering, oil emulsification, or oil viscosity for use of Dasic EcoSafe OSD cannot be specified because of the huge differences in chemistry of various oils and conditions of a specific spill scenario. If effective use of Dasic EcoSafe OSD could mitigate spill impacts, a field-based monitoring protocol used to assess effectiveness of the actual oil encountered during a spill is recommended.

(12) PHYSICAL/CHEMICAL PROPERTIES [§ 300.915(a)(12)]

(13) IDENTIFICATION AND CONCENTRATION OF PRODUCT COMPONENTS [§ 300.915(a)(13)]
Under § 300.950, you may only claim as Proprietary Business Information (PBI) the concentration, the maximum, minimum, and average weight percent; and the units of each component of the total formulation as identified in § 300.915(a)(13) and (14) and as applicable. All other product information submitted to EPA as required under § 300.915 and § 300.955 will be available for public disclosure upon submission, without further notice to the submitter.

(15) DATA, METHODOLOGY AND SUPPORTING DOCUMENTATION FOR LEVELS OF THE FOLLOWING [§ 300.915(a)(15)]:

• ≥70% for Strategic Petroleum Reserve Bryan Mound test oil at 5^oC; and
• ≥75% for Strategic Petroleum Reserve Bryan Mound test oil at 25^oC. 

DISPERSANT TOXICITY TESTS AND LISTING CRITERIA [§ 300.915(b)(2)]
Listing Criteria: Dispersant tested alone must demonstrate:

• For acute toxicity a median lethal concentration for 50% of the test species (LC50) at the lower 95% confidence interval greater than 10 ppm.
• For developmental toxicity the inhibition concentration for 50% of the test species (IC50) at the lower 95% confidence interval greater than 1 ppm; and
• For sub-chronic toxicity the No Observed Effect Concentration (NOEC) greater than 1 ppm.