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HomeMy WebLinkAboutMulti-Hazard Mitigation Plan: 08. Lava And Vog CIVIL DEFENSE AGENCY COUNTY OF HAWAII 920 ULULANI STREET HILO,HAWAII 96720 r f 8. Lava and VOG Chapter 8:Hazard Analysis—Lava and VOG CHAPTER 8 - LAVA FLOWS, VOLCANIC GAS, AND ASHFALL 8.1 Hazard Description 8.1.1 Lavallolcanoes The Island of Hawaii is composed of five volcanoes,two of which(Mauna Loa and Kilauea) have been very active in the past 100 years and pose the most immediate threat to life and property. A third volcano, Hualalai, last erupted in 1801 and has the potential to erupt again within our lifetime. Mauna Kea last erupted approximately 3,500 years ago. Kohala, considered extinct, is the oldest volcano on the island and last erupted approximately 60,000 years ago. Most of the eruptions of Hawaiian volcanoes are not explosive(therefore ash fall is not a ma- jor concern) and are characterized by relatively quiet outflow of very fluid lava. These erup- tions, however, can still be quite hazardous because they may be erupted in huge volumes, and on steeper slopes, the fluid lava can rapidly travel many miles from its source.33 Lava flows present potential threats to homes, infrastructure, natural and historic resources and entire communities. The areas exposed to the highest risk from lava flows are those situated downslope and in close proximity to the active rift zones of Mauna Loa and Kilauea. Steep slopes may allow lava flows to move quickly from the summit to the ocean in a matter of hours. Besides the direct threat of inundation, lava flows may also cut across a community's single roadway escape route limiting the amount of time available for evacuation. The following briefly profiles the volcanoes that pose potential hazards. • Mauna Loa, like most Hawaiian volcanoes, has a summit caldera and two radiating rift or fracture zones. Comprising approximately 50% of the island of Hawaii,Mauna Loa poses a lava hazard threat to the districts of South Hilo, Puna, Ka'u, South Kona,North Kona and South Kohala. Mauna Loa eruptions can occur at the summit, from vents on the southwest rift zone and the east rift zone and on the north and northwest flanks of the volcano. • Kilauea is one of the world's most active volcanoes and over 90% of its surface is covered by lava less than 1,100 years old. All of Kilauea's eruptions have occurred either at its summit, or along one of two rift zones that extend from the summit to the coastline on the east and southwest flanks of the volcanoes. Eruptions on the east flank of Kilauea are a threat to portions of the Puna district. Eruptions on the southwest flank of Kilauea are a threat to land within the Hawai'i Volcanoes National Park and the district of Ka'u. • Hualalai is much older than Kilauea and Mauna Loa and has not erupted since 1800-1801. Eruption activity on Hualalai has been far less frequent with 25% of the volcano covered by flows less than 1,000 years old. Hualalai has erupted near its summit, along the northwest and south-southeast rift zones and from vents on the north flank of the volcano. Eruptions on Hualalai threaten land within the North Kona district. 33 USGS Fact Sheet 074-97. 8-1 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG 8.1.2 VOG "VOG,"coined from "volcanic smog"but standing for"Volcanic Gas", is a term used by the public in Hawaii to describe hazy conditions caused by gaseous emissions from Kilauea volcano. Vog is created when Volcanic Gases (primarily oxides of sulfur, S02)react with sunlight, oxygen and moisture. The result includes sulphuric acid and other sulfates. VOG is made up of a mixture of gases and aerosols which makes it hard to study and potentially more dangerous than either on their own. The S02 gas in VOG is greater near the sources (Halema`uma`u and Pu`u `O`o vents). S02 levels are lessened further away or upwind from the vents. Vog mostly affects the Kona coast on the west side of the island of Hawaii,where the prevailing trade winds blow the vog to the southwest and southern winds then blow it north up the Kohala coast. The haze caused by vog may be heavy in West Hawaii, but the S02 levels are typically lower due to the geographic distance from the sources. One cannot judge the amount of S02 in the air or its danger to humans and plants by how heavy the vog appears, S02 levels can be high with only light vog. 11*61 a .r ,LL Figure 8-1. Volcanic Gas Emissions at Kilauea Volcano's Summit Vent on May,2009 8-2 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and i Figure 8-2. Aerial view - islartdofHawai`i VOG —Halema`uma`u Vent - of 1 wing circulation of prevailing winds, 1 Figure8-3. Aerial view of Hawai'i showing circulation of VOG_ Island of �Ianc�of Island o *� Kaho`olawcLan�:p' Moloka` Island of Hawaii ` �—Halema`mna`u Vent `'- under prevailing 34 Tmage taken from National Aeronautics and Space Administration(NASA)Earth Observatory Website, Retrieved on October 12, 009 from • 8-3 Hawaii County Multi-Bazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG 7;"N 16J`W 159"W 541W 154'W 152.:.* i Hawail (blg Island) Sulfur Dloxlde Mass(meMc tans) :: 15 3P Figure 8-4. Concentrations of SOz under prevailing winds in the Main Hawaiian Islands,April 30,200931 8.1.2.1 The Chemistry of,' and Reactions Occurring in, Kilauea's Vog Plumes The vog plumes from Kilauea contain a variety of compounds, at varying concentrations, that could have adverse impacts on the downwind communities and environment. There are three primary sources of volcanic gases from Kilauea: Halema'uma'u, at the summit of Kilauea, the "TEB Vent", located on the upper Kilauea East Rift Zone (KERZ), and the ocean entry along the Puna shoreline. The compositions of each are generally different, and the compositions can vary depending on local and temporal conditions. 8.1.2.1.1 Halema'uma'u The Halema'uma'u discharge contains carbon dioxide (CO2), water vapor (H20), sulfur dioxide (S02), sulfur trioxide (S03) and smaller amounts of hydrogen sulfide (HzS), hydrochloric acid (HO), and hydrofluoric acid (HF), as well as a number of trace gases. Although most of the gases discharged are the result of degassing of magma(within or below 35 Image taken from National Aeronautics and Space Administration(NASA)Earth Observatory Website, Retrieved on October 12,2009 from http://earthobservatory.nasa.gov/IOTD/view.php?id=8800 36 Image taken from National Aeronautics and Space Administration(NASA)Earth Observatory Website, Retrieved on October 12,2009 from http://eartliobservatoty.nasa.gov/IOTD/view.php?id=8706 8-4 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG the recently formed pit) there can also be contributions (of water vapor, hydrogen sulfide, and sulfur trioxide) from lower temperature hydrothermal systems that surround the magma conduit below and around Halema'uma'u. Soon after the gases discharge from the magma or the conduit surfaces, they begin to cool and undergo a variety of internal reactions and reactions with the atmosphere. While in the gas phase all the above compounds are transparent but, with cooling, sulfur trioxide will rapidly combine with water vapor(from the plume or the atmosphere) to form a sulfuric acid (H2SO4) aerosol. Under relatively dry conditions, the sulfuric acid aerosol can be distinguished by its bluish cast; when abundant water is present, a dense white plume is formed. HCl and HF will also condense onto solid particulates, if the latter are present, or form aerosol droplets by combining with condensing water vapor. Under dry atmospheric conditions, the plume will drift downwind and mix with the air column which will decrease the dew point in the discharge plume and the aerosol droplets will dehydrate and disperse. Under moist conditions, the plume will remain hydrated and the aerosols will remain much more visible. Mixing with air will also lead to reactions between atmospheric oxygen and the sulfur compounds sulfur dioxide and hydrogen sulfide. Sulfur dioxide is the more reactive of the two, with reported half-lives as short as a few tens of minutes to as long as several days depending on the chemical constituents in the air mass (e.g. urban air pollution, marine air), as well as the intensity of ultraviolet radiation. Given the absence of significant sulfur dioxide in the vog plume by the time it reaches Kona, it's likely that the half-life in the Hawaii air mass is no more than a few hours. The oxidation of any hydrogen sulfide present in the plume occurs at a much slower rate where the half-life of HZS in the atmosphere may be a day or more. The oxidation of sulfur dioxide will result in the formation of additional sulfur trioxide/sulfuric acid aerosol (because sulfur trioxide is extremely hygrosocopic, it will extract nearly any and all available water vapor from the atmosphere to form the acid aerosol) to contribute to the dry haze in the downwind plume. The oxidation process will continue until all of the sulfur dioxide is converted to sulfuric acid. Mixing of the plume with the atmosphere also brings the plume constituents into contact with ammonia that is derived from biogenic decay processes occurring in tropical soils. In the presence of water, ammonia (NH3) forms a weak base (NH40H) that will react very rapidly with the sulfuric acid aerosols to form ammonium sulfate [(NH4) 2SO41, and with the hydrochloric and hydrofluoric acids to form ammonium chloride (NH4C1) and ammonium fluoride (NH4F) respectively. Although these ammonia salts are not as hygroscopic as sulfur trioxide, they are sensitive to atmospheric moisture levels and the optical density of the plume will vary depending on the relative humidity in the ambient air. Whereas the non-reactive gas phase components of the plume (e.g. carbon dioxide) will gradually disperse, the aerosols are subject to both gravitational settling, through a process called dry deposition, as well as scrubbing from the atmosphere by rainfall. Although the aerosols can serve as a source of condensation nuclei for raindrop formation, some studies 8-5 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG have suggested that the plume may be providing an overabundance of nuclei that have inhibited drop growth resulting in a decline in rainfall rates in Ka'u and South Kona. The sulfur dioxide as well as the dry deposition of the plume aerosols can cause a variety of adverse impacts on the downwind environment and communities: 1) Sulfur dioxide and residual acid aerosols (that haven't reacted with ammonia) have been found to have broad detrimental impacts on non-native and agricultural crop biota. (There is some evidence that native plants have developed a degree of resistance to sulfur dioxide and/or the acid constituents in the plume.) The farming communities in Ka'u and HOVE have seen extensive defoliation and leaf damage to both edible crops as well as flowering and ornamental plants (tomatoes, lettuce, roses, protea, etc.). 2) The acid aerosols have been found to substantially lower the pH of rainfall. In locations with limited rainfall (e.g. HOVE) the combined effect of dry deposition of acid aerosols onto roofs, along with acid rainfall, substantially lowers the pH (becoming more acid) of domestic rainwater catchment systems. The likely consequences of the acidified domestic water are increased corrosion of the metallic constituents of both the roof and the plumbing equipment, as well as potential adverse health impacts from consuming the water (e.g. weakened dental enamel, poor uptake of dietary minerals). Increased acidity of the rainfall also has the potential to increase heavy metal exposure from leaching lead from paint (manufactured prior to 1978 when lead oxide was banned from paint) or plumbing systems that have used tin-lead alloys in their solder. The acid will likewise increase corrosion to any exposed metal along the path of the downwind plume including fencing, water lines, water tanks, farm equipment, etc. Even in relatively dry downwind areas, severe corrosion will generate significant economic losses. The most likely process driving the corrosion is dew formation rather than the infrequent rainfall: during the evening hours, as the dew point temperature is approached, the hygroscopic acid aerosols will form an extremely corrosive film, with pH as low as 1, on metallic surfaces. With daily replenishment of fresh acid from dry deposition, and nightly condensation of moisture it's reasonable to anticipate substantially more rapid deterioration of exposed metal surfaces than would occur in similar environments not exposed to the plume acids. A further effect of the increased loading of acid onto agricultural lands in the downwind areas will be accelerated leaching of minerals from the soil column. To date, this process has not been fully researched and, hence, it's difficult to offer an assessment of the long-term impacts of acidification of rainfall on the agriculture communities downwind of Kilauea. 3) The dry deposition of the acid aerosols and ammonia salts will increase the exposure of the downwind environment and communities to chloride, sulfate, and fluoride ions. Whereas moderate dietary intake of chloride and sulfate ion are relatively benign, fluoride ion is both an essential element, at low rates of intake, but can be extremely 8-6 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG toxic at excessive levels of consumption. Recent surveys of domestic catchment systems in the area of HOVE and Volcano have shown that plume constituents are contributing chloride, sulfate and fluoride ions to catchment waters. HOVE water samples showed the higher concentrations of these ions, by factors of four to ten above those of Volcano, and reflect a higher integrated exposure to plume deposition than did the Volcano community. (The higher rainfall rates and flow through the catchment systems in Volcano is also likely to contribute to the lower values there.) The median values of all ions for both communities were considerably lower than drinking water standards but some samples from both the HOVE and Volcano areas did show values that were substantially higher than the median values and were much closer to drinking water limits. Hence, significant changes in the plume discharge rates or in weather patterns could warrant further monitoring of the catchment systems. Of potentially greater concern is the deposition of fluoride salts onto forage crops. The scientific literature has documented a number of events where sheep, cattle, and horses have suffered significant losses as a result of both acute exposure as well as chronic exposure and accumulation of fluoride salts by grazing animals. Although there have been a few anecdotal reports of symptoms of fluorosis by some ranchers on the Big Island, further investigations will be necessary to determine whether the forage crops are accumulating sufficient fluoride to be of concern in the downwind communities. 8.1.2.1.2 TEB Vent and Pu'u O'o The TEB vent, located on the Kilauea East Rift Zone (KERZ), is discharging gases similar to those at Halema'uma'u, albeit at different relative concentrations. Due to the dynamics of gas release from magma, the relative amount of carbon dioxide to sulfur dioxide is lower at the TEB vent than at Halema'uma'u and the concentrations of HCl and HF are somewhat higher. This discharge is also likely to have lower amounts of sulfur trioxide and hydrogen sulfide than the summit discharge. The sulfur dioxide emission rates from TEB Vent have ranged as high as 2000 tonnes per day but currently are in the range of 1000 tonnes per day or somewhat less. The chemical processes occurring in the TEB plume, are in most respects, identical to those occurring in the Halema'uma'u plume but, because of the vent's location on the KERZ, the trajectory taken by the plume (during normal trade wind conditions) is substantially different from that of the former. Whereas the Halema'uma'u plume is often affected by the upslope winds generated by daytime heating of Mauna Loa's flanks, the TEB plume is far enough off-shore that it only rarely affects the south-east flank of Mauna Loa. However, the TEB plume has shown a history of becoming trapped in the eddy system on the southwest and western flank of Mauna Loa and has consistently affected air quality on the Kona side of the island since the initiation of the Pu'u O'o eruption in 1983. With the onset of the Halema'uma'u eruption, the addition of its plume to that of TEB has produced further deterioration in the Kona air quality. 8-7 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG Because the TEB plume has traversed a significantly longer trajectory on it's path to the Mauna Loa eddy system, nearly all the sulfur dioxide from the discharge has been oxidized to sulfate, and a higher proportion of the acid aerosols have been neutralized to ammonium salts,than has occurred in the Halema'uma'u plume during its trajectory across Ka'u and into the HOVE area. As a result, under trade wind conditions, the adverse effects of the TEB plume on the Kona community are likely to be more moderate than has been seen in Ka'u and HOVE. However, when southerly winds occur around the island, the TEB plume is carried across the upper Puna area and across into the Hilo area and surrounding communities. Under those conditions, the TEB plume carries abundant sulfur dioxide and acid aerosols. Due to the relative infrequency of these conditions, there's been little documented adverse affect beyond the nuisance effects of poor air quality. Under prolonged or frequent southerly winds, the more populous Hilo and Puna communities would likely experience similar, or even worse, impacts that have been documented in the Ka'u and HOVE communities. 8.1.2.1.3 Ocean Entry Plume The steam and gas plume generated when lava flows into the ocean has a substantially different composition from that of Halema'uma'u and TEB. Whereas in the latter, sulfur dioxide is a major contributor to the acid aerosols present in their plumes, the ocean entry plume contains only minor amounts of sulfur dioxide but much higher concentrations of hydrochloric acid. The latter is generated by the reactions occurring when seawater is boiled to near dryness by its interaction with the lava. The ocean entry plume is also rich in steam and aerosolized seawater, the hydrochloric acid tends to precipitate out more rapidly and, hence, poses a greater threat only in close proximity to the source and a much lesser threat further downwind. Further alleviating the potential for the ocean entry plume to adversely impact the community is that, under the more common trade wind conditions, the plume is driven offshore and over the ocean where most of the aerosols are precipitated out. Hence, the ocean entry plume is only of concern in the immediate vicinity of the shoreline and only during conditions that would bring the plume ashore. 8.1.2.2 Health Effects Tt appears that the levels of vog normally present do not produce acute symptoms although they may produce respiratory problems. Sulfur dioxide is irritating to the eyes, nose, throat and respiratory tract. Short-term exposure to elevated levels of SO2 may cause inflammation and irritation, resulting in burning of the eyes, coughing, difficulty in breathing and a feeling of chest tightness. "Sensitive groups" are children and those with pre-existing respiratory conditions such as asthma, emphysema, bronchitis, and chronic lung or heart disease. These people are especially sensitive to SO2 and may respond to very low levels in the air. Prolonged or repeated exposure to higher levels may increase the danger. Other common symptoms of vog exposure include the following: • Headaches • Breathing difficulties • Tncreased susceptibility to respiratory ailments • Watery eyes • Sore throat 8-8 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG 8.1.2.3 Effects on Plants Sulfur dioxide must enter leaf mesophyll tissue, through stomata (natural openings in leaf surfaces that regulate gas exchange), to cause plant injury. Once S02 enters the moist mesophyll tissue, it combines with water and is converted to sulfuric acid which burns plant tissue. The general effects of S02 exposure to plants may vary and depend upon plant species, age, and the S02 dosage; these effects may include: • reduced seed germination • enhanced susceptibility to other diseases • foliar necrosis (spots,blight) • epicuticular wax erosion • rupture of epidermis,plasmolysis • reduced chlorophyll content • increased membrane permeability of plant leaves • decreased plant growth(root length, shoot length,leaf numbers) • plant organ or entire plant death 8.1.3 Ashfall Large amounts of ash were deposited both up- and down-wind from the large explosive events of 1790 and 1924. By contrast, the 2008-ongoing Kilauea summit eruption has been persistently producing small amounts of ash punctuated by brief periods of increased production. HVO ash leachate analyses of samples collected near Halema'uma'u after explosive events in March and April found high levels of fluoride and some metals (cadmium, copper, lead, and chromium for example). These levels were elevated but not high enough to warrant immediate concern because of the low ash emission rate measured, even during explosive events. Substances like fluoride could be of concern downwind of any eruption if substantial accumulation occurs, either by increased ash deposition or by a significantly prolonged eruption. 8.2 Significant Historic Events The recorded history of volcanic activity in Hawaii begins with the arrival of the Christian missionaries in the early 1800's and those that are known from oral traditions of the Hawai- ians. Additional information on prehistoric eruptions is based on geologic mapping and dat- ing of old lava flows. 8.2.1 Mauna Loa Mauna Loa has had 33 historically recorded eruptions, most of which have occurred at the summit. Approximately 25% of the eruptions have started on the east-northeast rift zone and another 25% began in the southwest rift zone.37 During the period from 1832 to 1950, 37 Draft Lava Flow Hazard Mitigation Plan,2002 8-9 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG Mauna Loa averaged one eruption every 3.6 years.3s Since 1950, eruption activity on Mauna Loa has slowed considerably. The two eruptions since 1950 include a 1-day summit eruption in 1975 and a 3-week eruption on the northeast rift zone which advanced to within 4 miles of Hilo. Six eruptions from Mauna Loa have reached the ocean since 1859. The 1859 eruption on the northwest flank of Mauna Loa lasted approximately 300 days and reached the ocean north of Kiholo Bay in the North Kona district. Between 1868 and 1950, 5 lava flows have reached the ocean from eruptions on the southwest rift zone of Mauna Loa. These flows traveled quickly with 4 out of the 5 reaching the ocean in 3 to 48 hours.39 These flows entered the ocean in the South Kona and Ka'u districts. The eruption of 1950 destroyed the Ho'okena- mauka village in South Kona with the swiftly flowing lava traveling 14 miles in only 3 hours. Although the lava flow also crossed the area's only highway in two places, the residents of the village escaped unharmed.411 8.2.2 Kilauea Kilauea was almost continuously erupting at its summit caldera from the beginning of historic records up until 1924. Since 1955, most of the activity has occurred along the east rift zone. The latest eruption of the cast rift zone began in 1983 and is still ongoing as of the date of this report. The southwest rift zone has been less active with only 5 eruptions in the past 200 years; the latest was in 1974.41 April 1, 1955 (FEMA DR-32) Hawaii County experienced approximately$12.6 M in damages. About 1,580 hectares (3,900 acres) were covered by 108 million cubic meters (141 million cubic yards) of lava, mostly a'a. Of the covered land, about 450 hectares (1,100 acres) were under cultivation in the Kama'ili, Kehena, Ke'eke'e, Kau'eleau, and Kapoho areas. Approximately 10.1 km (6.3 miles) of public road were buried, as were many kilometers(miles) of cane-field roads. Iwasaki Camp, in Kama'ili near the upper big bend in the road to 'Opihikao, was overrun, but fortunately some of the houses and all personal belongings had been removed. Tragically, surviving remnants of the camp were destroyed on the last day of the eruption, May 26. In all,21 houses were overrun by 'a'a during the eruption January 21, 1960("1960 Kapoho Eruption of Kilauea Volcano Hawaii") (FEMA DR-96) The eruption of Kilauea ended on December 21, 1958; however the reservoir beneath the summit was filled with lava. Tine earthquakes were recorded near the summit of Kilauea and 38 Macdonald,G.A.,A.T. Abbott,F.L.Peterson,Volcanoes in the Sea(2d ed.),University of Hawaii Press, 1983. 39 Hetiker, 1990 40 USGS Fact Sheet 074-97 41 Heliker,1990. 8-10 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG on January 12, 1960, more than 1000 earthquakes were recorded north of Kapoho. On January 13, 1960, the volcano erupted, destroying the villages of Koa'e and Kapoho. Volcanic gases were also a significant health issue during this eruption. Figure 8-5. Photograph of 1960 eruption taken 10:00 am January 14,1960 May 18, 1990 (FEMA DR-864) Between 1983 and 1990, lava flow from the Kilauea volcano struck communities along its southern coast. This eruption is the volcanoes most destructive in the past 100 years. In 1990, it moved through the entire community of Kalapana.42 It has destroyed 210 homes, a visitor center at the Hawaii Volcanoes National Park, 8 miles of highways, and historical and archaeological sites. 8.3 Probability of Occurrence 8.3.1 Hazard Areas The U.S. Geological Survey has prepared maps showing volcanic hazard zones in Hawaii County. The "Volcanic and Seismic Hazards on the Island of Hawaii," 1990, authored by Christina Heliker and published by the U. S. Geological Survey, describes the lava flow haz- ard zone maps (see Figure 8-6) as follows: Maps showing volcanic hazard zones on the island of Hawaii were first prepared in 1974 by Donal Mullineaux and Donald Petersen of the U.S. Geological Survey and were revised in 1987. The current map divides the island into zones that are ranked from 1 through 9 based on the probability of coverage by lava flows. Other direct hazards from 42 USGS Fact Sheet 074-97 8-11 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG eruptions, such as tephra fallout and ground cracking and settling, are not specifically considered on this map; however, these hazards also tend to be greatest in the areas of highest hazard from lava flows. Hazard zones from lava flows are based chiefly on the location and frequency of both historic and prehistoric eruptions. The hazard zones also take into account the larger topographic features of the volcanoes that will affect the distribution of lava flows. Finally, any hazard assessment is based on the assumption that future eruptions will be similar to those in the past. Hazard zone boundaries are approximate. The change in the degree of hazard from one zone to the next is generally gradual rather than abrupt, and the change can occur over the distance of a mile or more. Within a single hazard zone, the severity of hazard may vary on a scale too fine to map. These variations may be the result of gradual changes that extend across the entire zone. For example, the hazard posed by lava flow decreases gradually as the distance from vents increases. There may be abrupt changes, however, in the relative hazard because of the local topography. For example, the hills behind Ninole stand high above the adjacent slopes of Mauna Loa and consequently are at a much lower risk from lava flows than the surrounding area, even though the entire area is included in a single zone. To determine the hazard differences within a single zone,more detailed studies are required. Table 8-1 provides the legend for the Lava Flow Hazard Zone Map. Zone 1 is the most haz- ardous area and includes the summits and the rift zones of Mauna Loa and Kilauea which have been the most active in historic time. Zone 2 includes those areas adjacent and down- slope of active rift zones. Zone 3 areas are gradually less hazardous than Zone 2 because of greater distance from the recently active vents and/or topographic conditions make it less likely to be covered by lava. Zone 4 includes all of Hualalai where the frequency of eruptions is lower than on Kilauea or Mauna Loa.43 It is anticipated that volcanic gases will also be a significant hazard during the next eruptions of Mauna Loa and Hualalai. 43 Hecker, 1990 8-12 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG Table 8-1. Legend for Lava Flow Hazard Zone Ma Hazard Zones for Lava Flows Percentage of area Percentage of area covered by lava since covered by lava in last Zone 1800 750 years Explanation Includes the summits and rift zones of Kilauea and Mauna Loa Zone 1 >25% >65% where vents have been repeatedly active in historic time. Zone 2 18-25% 25-75% Areas adjacent to and downslopc of active rift zones. Areas gradationally less hazardous than zone 2 because of greater distance from recently active vents and/or because the topography Zone 3 1-5% 15-75% makes it less likely that flows will cover these areas. Tncludes all of Hualalai,where the frequency of eruptions is lower Zone 4 approx.S% <15% than on Kilauea and Mauna Low.Flows typically cover large areas. Areas currently protected from lava flows by the topography of the Zone 5 none approx.50% volcano. Zone 6 none very little Same as Zone 5. Zone 7 none none 20%of this area covered by lava 3,500-5,000 years ago. Zone 8 none none Only a few percent of this area covered in the past 10,000 years. Zone 9 none none No eruption in this area for the last 60,000 years- 5 Volcanic Harud Zone -2 _3 4 Z 5 wry.. 6 �7 - -8 -9 Figure 8-6. Lava Flow Hazard Zone Map 8-13 Hawaii Countv Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis-Lava and VOG Future large eruptions of Mauna Loa's southwest rift zone and Hualalai in Kona may evolve quickly and produce lava flows that travel up to tens of kilometers in a few hours or less, generally faster than velocities expected for typical flows at Kilauea. Radial vent eruptions on Mauna Loa's north and west flank occur outside the rift zones (e.g., 1859 eruption and 1877 submarine eruption) and could represent a greater problem than rift zone eruptions because of their potential to begin closer to or within developed areas. 8.4 Risk Assessment Lava risk can be assessed fairly easily, at any property where lava inundation occurs a total loss is assumed. Therefore if the theoretical recurrence interval of lava inundation at an area is known the annual loss (AAL) can be computed by multiplying the total value of the exposed properties by the annual probability of lava inundation. The results of this analysis are included in Table 8-2. The projected AAL for lava inundation is about$24 Million/year. Table 8-2. Lava inundation AAL of ftildmg Stuck in fi a d 7.. T-1 Di-ict 1 2 3 4 6 7 8 9 Fcpusore Vslue($) AAL ATI.R by Ttact 15001020100 Psp 1'n,WA_ 0% 0% 1, 0% ,0% 0% 0% 100% I, $ 530302,383 $ 1,051 0.0002"1� 150010?0200 Hik,Uppu W,iak,,F,,-t Rri,t 0%. 0%. D%. D% D% 0% 0% 10 D%. $ 232,(,OR,007 $ 470 0.0002% 15001020300 Ho:Pimco-Doa-ntown 0% 0% 100%. 0%. 0% 0% 0% D%. 0%. S 758,039,632 S 781052 0.1032% 150D102040D llilo:Villa Tranca-Kaiko'o 0'% 0% 100%, 01Y., 0"/" 0"/" 0% 0% 0"... $ 632,534,825 $ 652.572 0.1032'% 15001020500 Hilo:Uuivu itv-H..,kt, 0151) 0% 100 0%. D%. 0"/" 0151) 0% 0 S 1,386,852,7R1 $ 1,430,784 0.1032% 15001020600 Milo:K­,kuL Pazmcwa 0"l) 0'% 100%, D% D"/" 0"/" 0'% 0'% 0%. S 1,176,770,100 $ 1,214,046 0.1032'% 150 0 102 0 70 1 Milo:Poomko W,,) 0"< 100':.. 01Y.. 01% 0"/" 0"<' 0"< 0':.. S 154,714,65() S 572,286 0.1032'% 15001020702 IIik,Kuvraibri 0%" 0"6 100'%. D"... D'%. 0'% 0"6 0'4) 0"... S 555,696,175 $ 573,299 0.1032'% L50U LO2D801 LIiW:Kukuau-K­vnn 0"<, W/, 100'5., 01Y.. D"/" 0"/" 0"<) w/, 01Y.. S 504970,475 $ 520,966 0.1032"/" 15001020802 Hik,Piihonua-Kxwx , 0.", 0'41 100".a (A D"/" 01% 0"," 0'% 0'S�. S 717,253,225 S 739,974 0.1032% 15001020900 Illlo:IIol.i 0"6 0'% 100"... D%, D"/" 0"/" 0'% 0'% 0%. S 568,778,950 $ 586,796 0.1032'% 1 500 1 021 00 1 Tower Ke,a 0% 01% 100% D% D% 0% 11 01% 0".a S 1,699,785,371 S 1,753,629 D.1032% 15001021002 Kctu,-Voktmo 0"," 0'41 100'% 0% 0% 01% 0"," 0'41 01% S 1,448,609,457 $ 1,444,497 0.1032% 15001021100 45% 45% 10% D% D% 0% 01% 01% 0% $ 1,082,017,600 $ 7,629.913 0.7052% 1 500 1 021 200 Ku'u 01% 501% 25% D% p"/" 25% 01% 01% 0% S 767,986,750 $ 778.265 0.1013% 1 5001 021 300 South Kons 0% 55% 45% 0% 0% 0% 0% 0% 0% S 658,165,575 $ 709,210 0.1078% 1 500 1 021 400 KeJbkkka-Czptsin Cook 01% 0",� I W% 0".0 0% 0% 0"1� 01% 0 11.o S 442,919,125 $ 456,949 0.1032% 1 Soo 10215(11 K.J.- 0-1� 0% W. 100% 11% (1% 0-1� 0% W. S 2,_535,736,450 S 274,707 00108% 1 5001 021 50 2 TT-LIsi 0°1� 0% 0% 100% 0% 0% 0% 0°1� 0% S 609,567,725 S 66,037 0.0108% 15(101021503 K-,,0o,n KC1,,kck. 11% 0% 1(10% 0% 0% (1% 11% 0% 0% S 1422,217,132 S 1467,263 ()1032% 1 5001 021 601 Kzihm 0% 111, 100% 0% (N IN 0% 111 D% S 1,611,1(7,271 1 1,666,331 01032% 1 5001 021 60 2 Kahu1ui-Ks oAm 1u 01, 005" 0% 100% 0% 0% 0°6 0% 0% S 1,369,362,350 S 148,349 0.0108% 1 51101 021701 llaaW knkia 0-1� 0% IN 100% 0% 0% 0-1� 0% IN S 3,43`1,194,975 S 372,582 1101110% 1 51101 0 21 70 2 W,,, e,-Puu An I.1l 0% 111 111% D.. 0% 0% 0% X0°,� 111% S 1,270,321,125 S 135,013 0.01 IIC% 15001021X00 N-1,K.ho,, (1% 1)% 11% 0% 0% 0% 0% 111 100% S 717,133,107 S 5,176 0.000X% 1 51101 021 900 H­Lk, 0% 111 11% 0% 11% 11% 11% 1110% 0% $ 431 633,5011 $ 872 11110112% 1500102200(1 Paahau-P:tauilo 0% 0% 100% 259,500,950 $ 524 0.0003% 15001(123100 North Hilo (1% 11% 1110% (1% S _3,181,475 $ 449 11110113% Total $ 27,608,011,843 S 24,034,868 0.0871 8.5 Mitigation Strategies 8.5.1 Previous/Current Efforts The Hawaiian Volcano Observatory (HVO) is at the forefront in advancing our capabilities to address volcanic hazards. HVO was established in 1912 at the summit of Kilauea and has been operated continuously by the U.S. Geological Survey (USGS) since 1947. The HVO studies current geologic activity at Hawaii's volcanoes, past eruptions, earthquakes and other volcanic hazards. This information is utilized to provide timely warnings to local officials and the public, to assess long-term volcano hazards, and to make hazard-zone maps that help guide land-use planning decisions. Current eruptions are tracked by HVO scientists and the information provided on projected lava flow movements help public safety officials 8-14 Hawaii Countv Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG determine the need for evacuation or other precautions.44 A current lava flow inundation map for Mauna Loa that identifies inundation areas is shown in Figure 8-7. In order to coordinate the efforts of HVO and other involved agencies, the "Lava Flow Hazard Mitigation Plan" (November 2002) identified several tools to improve planning and emergency response for lava flow hazards: • Probabilistic Hazard Maps. The HVO is continuing to work towards developing Probabilistic Lava Flow Hazard Maps for the Island of Hawaii, which will replace the existing Island of Hawaii Lava Hazard Zones 1-9. (See hqp://hvo.wr.us g s lzov/products/OF98794/OF987toe.html) Instead of boundaries designating whether lands are inside or outside a lava hazard zone, such maps would show gradational colors or patterns for increased or decreased hazard. The existing hazard zone maps have led to large jumps in insurance rates across narrow zone boundaries depending on what zone the property is in. With probabilities, insurance companies could, if they chose, apply a sliding scale of rates on the basis of probabilities, so that there would rarely be large rate differences across short distances. It is anticipated that the final product will be a single map showing generalized probabilities of lava flow inundation over a specific period of time. 44 USGS Fact Sheet 074-97 8-15 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG Z U S G S ram 77,1 1 SOUTH 0- KIPAHOEH E'_ • ­UT ­11, Ho X 7L-O� gf! t7 + ........ ....... ,v "V Figure 8-7. Lava Flow Inundation Map 8-16 Hawaii Countv Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG 8.5.1.1 Lava Directional Maps and near real time Modeling Capabilities Once an eruption is imminent, emergency managers would benefit from information forecasting possible lava flow direction as well as the size and speed of the flow. Combining predictive modeling results with GIS data and information, emergency managers will better be able to identify populations at risk and potential social and economic impacts. Towards this end, HVO is in the process of developing two related products: 'Lava shed Map,' which predicts the gravity-driven directional path using the hydrologic functions of GTS and a digital elevation model (DEM), and a 'Lava Flow Atlas,' which portrays the paths of known lava flows in the past. Together, the products will indicate the range of directions and possible paths that the lava from specified vents can be expected to take. Besides direction, a predictive model needs a range of size and speed of the flow. These estimates must be based on observations and measurements of past Hawaii lava flows and knowledge of the terrain, coupled with what is known of any precursory phenomena, such as earthquakes. HVO is currently compiling all available information on lava flow behavior during each post-1840 eruption in order to characterize these quantities. 8.5.1.2 Monitoring and Warning Capabilities Volcanic monitoring and surveillance are based on the movement of molten rock or magma and/or volcanic gas beneath a volcano that will precede any large eruption. HVO uses three primary techniques to detect magma and monitor its movements: 1. Monitoring of volcanic earthquakes. Any movement of magma requires it to push its way through the rocks of the earth's crust. This causes fracturing of rock, and movement along faults, resulting in earthquakes that can be detected at the earth's surface. Specific types of seismicity can be "mapped" to particular regions under the volcano allowing scientists to plot the passage of magma. 2. Monitoring of ground deformation. As the magma approaches the surface of the earth, and moves into the conduit below the vent of a volcano,the displacement of the surrounding rocks to make way for the magma causes the ground surface to move and the volcano to swell. This rising or swelling can then be used to assess the depth of the magma body and often give some idea of its volume. 3. Monitoring of'the chemistry of'volcanic gases. Magma deep in the earth contains gases dissolved in it. As the magma rises to shallow levels, these gases are released and, because they are mobile when compared to the sluggish liquid magma, they rise more rapidly to the surface and are discharged through gas vents. The composition and temperature of these gases give clues as to how close magma is to the surface. HVO aims to provide weeks to months warning guidance of potential eruptions at Mauna Loa and hours to days warning at Kilauea. Precursors before an eruption of Hualalai may last for hours to weeks, though this time period has not been tested because no eruption has occurred since monitoring was started on Hualalai. HVO has 65 seismic stations on the island of Hawaii to monitor volcanic earthquake activity. Moreover, HVO has scores of ground-movement monitoring stations, of which more than 20 are continuously reporting GPS systems, 11 are electronic borehole tilt-meters, and 4 arc electronic deep borehole strain-meters. All field instruments radio signals to HVO in real time for evaluation and interpretation. 8-17 Hawaii Countv Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG 8.5.2 Future Plans Project Description Status NOAA HYSPLIT Model tries to forecast SO2 Based on wind modeling of Being used in an evaluation hourly based on meteorological conditions and dispersion over the course trial at HCDA and USGS emission rates of the Halemaumau and Pu'u of each day. HVO. NOAA HYSPLIT O'o sources. modeling was initiated by John Rays of the National Park Service with Roland Draxier from NOAA.The current effort is a 2-yr cooperative agreement between HVO and UHM (Steve Businger).Tere are two other parts to the current gas dispersion study:a)UHM will develop a pilot near real- time gas emission rate monitoring deployment and b)HVO will install a dense SO2 and meteorological monitoring network to better understand near-vent gas dispersion. Develop probahilistic lava flow maps and One of the technical issues Preliminary 100-year% modeling: is in how to consider probability of inundation USGS is in the process of modernizing the lava overtopped prior flows that maps are being developed in become concealed by more 2009. Need to resolve under- inundation probabilistic maps. Based on recent flows. Otherwise, sampling of hazard before average recurrence intervals with a Poisson the map probabilities may releasing. Could either use probabilistic model. be too low. borings and/or simulation to refine. Enhanced interactive Lava Flow Modeling The model does not Received FEMA funding and Program FlowGo 11 compute a rate of advance under development: The The study will provide updated information to of the terminus of the flow. most likely candidate for use identify at-risk areas as a lava flow progresses, Land cover,roughness,are of this model is the upslope factors that are not a part of part of Mauna Loa. and assist in locating highest hazard areas as the present model flows approach. formulation,but which Computation based on cooling of lava and would be needed to be increase in viscosity as it moves down the slope considered in the model to within a lavashed.It estimates where the initial estimate a rate of flow. The flow is likely to go.There is a random model does not include parameter term that allows the flow to follow a build-up of deposited lava non-deterministic path,enabling a Monte Carlo affecting the path of approach. subsequent flows. Evaluate economic impacts and critical To be based on probabilistic The existing lava hazard zone infrastructure and facility vulnerability from lava hazard mapping under maps have been used to lava inundation development by HVO determine expected losses to residential construction in each district Community testing of pH and metal content in Conducted by CSAV at water catchment systems community workshops 8-18 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Hazard Analysis—Lava and VOG Conduct Public Meetings on VOG/SO2 and Conducted by CSAV at how to mitigate it's effects community workshops Study of vog mitigation effectiveness T. Removal technologies being tested II. Tests to be run A. Air conditioner A. Base case test: B. Dehumidifier 1) standard volume—20'or 40'container— C. Particulate filters/Electrostatic sealable Precipitator 2) source of S02;source of S03. Former would D. Fan with chemically treated fabric be simply a tank and regulator for sulfur filter dioxide;latter is a hot plate and pyrex glassware with concentrated sulfuric acid;fan for uniform The base case would give us most of the mixing;relative humidity instrument. information that we will need to make 3) sensor for SO2(electrochemical sensor with recommendations. We will undoubtedly get data output would be adequate);nephelometer questions on the rates of removal and the most for aerosol sulfuric acid(sulfur trioxide); appropriate size of the unit that the homeowner humidifier may want to purchase so running the Base Case 4) Run baseline to determine what the natural rate +1 test with two or three different size units of decay is in the container volume:inject would help us provide answers to those known volume of S02,or to a target SO2, questions. concentration;mix for uniformity(test run with electrochemical SO2 detector);track natural Base Case+2 would only be useful for the decay rate of 5O2. Run similar test with sulfur obsessives. It is quite likely that the largest trioxide while monitoring with nephelometer. effect of the fabric surface materials will be to 5) Under uniform conditions,inject SO2/SO3 and accelerate the removal rate at high run:air conditioning unit;dehumidifier;a concentrations. But,as removal proceeds,the particle filter/electrostatic precipitator;fan and fabric surface materials will likely give up some bicarbonate fabric particulate filter;and track of the SO2 that was taken up by the fabrics. rate of decline of SO2/5O3. For AC and (SO2 is kind of a sticky molecule and will dehumidifier will need to do additional runs attach itself to available surfaces—much like while operating a humidifier since the water vapor is taken up in fabrics.) The sulfur effectiveness of the method will depend on trioxide/sulfuric acid aerosols,once taken up on condensation of water on the chilling elements. the surfaces will probably not come back off at B. Base Case+1 a measurable rate. 1) Run 5)above using two or more levels of air flow in each device to determine what the relative increase in rate of removal can be effected with higher air capacity. C. Base Case+2 1) Run 4)&5)above with"domestic materials"in the container volume. The nature of the surfaces in the test volume will likely affect the natural rate of decline of the gases/aerosols. Can probably use hanging fabrics and carpeting as surrogates for furniture and drapes. 5-19 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Appendix A Where to Find Information about Vog, Sulfur Dioxide(S02), Particulates, and Volcanic Ash Hawaii Volcano Helpline On August 1,2008,the Hawai'i Department of Health announced the introduction of a toll-free phone helpline where the public can obtain up-to-date information on Vog and volcanic emissions.The toll-free number is: (866)767-5044. The helpline is staffed by trained professionals Monday-Friday from 5 AM to 5 PM,and on weekends from 9 AM to 5:30 PM. Recorded messages,updated daily,are accessible 7 days a week,24 hours a day(including holidays)and include information on daily S02 and particulate levels from monitoring stations on Hawai'i Island. Hawaii County Civil Defense(HCCD) Emissions from Kilauea Volcano Brochure provides information on sulfur dioxide emissions,vog,ash fall,protective health measures,and relevant contacts.The brochure was developed through a partnership between County,State,and Federal agencies,and the American Lung Association of Hawai'i. htty://co.hawaii.hi.us/ed/emissions brochure.pdf Kilauea Eruption Update Website includes link to the"Emissions from Kilauea Volcano"brochure,but primarily provides information on Kilauea's current eruption and frequently asked questions about lava flows. http://www.lavainfo.us/ United States Geoloeical Survey (USGS) Sulfur Dioxide,Vog,and Volcanic Ash:Frequently Asked Questions about Air Quality in Hawaii Recent(2008)detailed FAQ document covering a wide range of issues on S02,Vog,and Ash. Includes links to many other related websites and documents. httn://hvo.wr.usas.aov/hazards/F'AO S02-Vog-Ash/main.html Webcam of Halema'uma'u vent at Kilauea Summit Live Panorama of Halema'uma'u vent in Hawaii Volcanoes National Park. httv://hvo.wr.usgs.gov/cam3/ Hawaiian Volcano Observatory Website includes recent Kilauea eruption update and summary,information on volcanic hazards, and weekly Volcano Watch articles. Search the Volcano Watch archive for information about vog and volcanic gases. htty://hvo.wr.us g s.go v/ A8-1 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Appendix A Volcanic Air Pollution—A Hazard in Hawal'i Fact Sheet 169-97 Information about volcanic air pollution(vog)in Hawai'I(revised June 2000) http://pubs.usgs.gov/fs/fs 169-97/ Volcanic Ash ...What It Can Do and How to Prevent Damage Website about ash—what it is and how to prevent or reduce its damaging effects. http://voleanoes.usgs ovg_/ash/ Volcanic Ash Fall­--A"Hard Rain" of Abrasive Particles Fact Sheet 027-00 Information about ash and its potential health threats and hazards. httn://Dubs.usgs.gov/fs/fsO27-O0/ Hawaii Volcanoes National Park(HAVO) Current S02 Conditions–Kilauea Summit National Park Service:Nature and Science–Explore Air Website Map showing location of the Halema'uma'u and Pu'u'O'0 gas plumes in HAVO and S02 concentrations(ppm)at the Kilauea Visitor Center and Jaggar Museum. http://www.nature.nps.eov/air/webcams/parks/havoso2alert/havoalert.cfm Sulfur Dioxide(SO2)Advisory Program National Park Service:Nature and Science–Explore Air Website Overview of sulfur dioxide monitoring in HAVO and advisory levels,plus links to more information about volcanic gases,volcanic pollutions,and air quality in Hawaii. htty://www.nature.nns.gov/air/webeams/narks/havoso2alert/havoadvisories.cfm#AdvisoryLevel Criteria Air Quality Information National Park Service:Nature and Science–Explore Air Website General information about air quality in HAVO. http://www.nature.nos.gov/air/Permits/ARIS/havo/ Hawaii Department of Health (HDOH) Frequently Asked Questions and Answers on Vog and Volcanic Emissions from Kilauea A six-page Q&A covering common questions and answers about Vog,monitoring,health effects,protective measures,and water catchment issues. httn://hawaii.gov/health/about/reports/vog aa.pdf Precautionary Measures for Elevated Sulfur Dioxide Levels on the Big Island Web page on sulfur dioxide(SO2)emissions from Kilauea Volcano,including links to Frequently Asked Questions about what S02 is,how it affects health,and how exposure can be minimized and recommendations by the American Lung Association. httt)://hawaii.gov/health/environmental/air/cab/cab precautions.html AS-2 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Appendix A Online Air Quality Data Maps showing air quality conditions in the Hawaiian islands. Data collected by HDOH real-time air quality monitoring network.Click on link to"On-line Air Quality Data".Includes S02, PM2.5,and H2S data on Hawai'i Island under link titled"Air Quality on Big Island",and just S02 data under link titled"S02 data on Big Island".Note that data is collected real time,but report on-line typically lags by about 2 hours. htty://hawaii.eov/health/enviror mental/air/cab/cab onlinedata/cab onlinedata intro.html Clean Air Branch(CAB) Website includes link to"Public Notification:Air Pollutant Exceedence on Big Island."This is a list by HDOH air monitoring location,of dates and specific levels recorded when there have been exceedences of the National Ambient Air Quality Standards(NAAQS). httv://Iiawaii.lzov/health/enviiomnental/air/cab/index.html Safe Drinking Water Branch(SDWB) Website includes information on a subsidized testing program for lead and copper in catchment systems that is available through the SDWB(lead or copper could be"leached"into catchments or related piping as a result of vog/acid rain impacts on roofs/gutters or piping that contain these metals).Website also includes link to other information on catchment testing and guidelines for safe construction and operation of catchments: httn://hawaii.gov/health/enviromnental/water/sdwb/raincatch/raincatch.html American Lung Association of Hawaii(ALA-H) Website provides information about vog—what it is and what to do about it and air quality in Hawaii. Links to other relevant sites. htt n://www.ala-hawaii.org/airgualitv.asn U.S.Environment Protection Agency Website EPA AIR NOW–Fine Particulates(2.5 micrometers and less)Air Quality Index for Hawaii. Indicates Good,Moderate,Unhealthy,etc."color-code"for Department of Health monitoring site locations,including Kona,Pahala,Mt.View,and Hilo.Also see health guidance messages associated with the color codes.Data includes"forecasted"condition regarding fine particulates for the next day. htti)://www.aimow.gov/ At home page,select"Hawaii"from drop down menu under banner headed"Local Air Quality Conditions and Forecasts". See condition/color code for particulate levels at various island locations.Click onto specific location city to see detail for that particular location and health message associated with level/color code at that location. S02-How Sulfur Dioxide Affects the Way We Live&Breathe Web page about S02—what it is,where it comes from,causes for concern,health and environmental impacts,and EPA's effort to reduce it. httn://www.epa.gov/air/urbanair/so2/index.html AS-3 Hawaii County Multi-Hazard Mitigation Plan Chapter 8:Appendix A International Volcanic Health Hazard Network(IVHHN) Website provides guidelines,databases,and publications on the health hazards of volcanic gas and ash. http://www.ivhhn.orc/ Hawaii Rainwater Catchment Systems (HRCS) Association Recommendations for Catchment Users Due to Increased Volcanic Activity Web page provides info on steps to take to minimize ash and debris in water catchment. httv://www.hawaiirain.orp-/news/index.phy UH Hilo,Center for the Study of Active Volcanoes. Website contains information on Coping with Vog from Halema'uma'u and links to information on Coping with Vog from Pu'uO'o,as well as Coping with Vog on Catchment Tanks. http://www.uhh.hawaii.edu/—nat haz/ Volcano School of Arts& Sciences,Volcano,Hawaii This website includes real-time data from S02 monitors at the charter school,as well as an S02 monitor located on 5`h Street in a nearby Volcano neighborhood.This school is located approximately 4 miles NE of the Halema'uma'u vent at the Kilauea Summit. httv://volcano-school.ora/ National Oceanic and Atmospheric Administration (NOAA) GOES-WEST satellite:a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes.The loop is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawaii volcanoes. The imagery automatically switches from infrared at night to visual during the day.Recently,it has been useful for tracking volcanic gas emissions from Halema'uma'u,Pu'u'O'o,and the Waikupanaha ocean entry during the day and hot lava flows at night. http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html National Aeronautics and Space Administration (NASA) MODIS satellite:a NASA satellite pair,Aqua and Terra,which passes over Hawaii twice a day. During daylight hours,the images are taken at about 11 am and 2 pm H.S..T.This imagery can be useful for tracking plumes,and can be viewed about 3-5 hours after acquisition at: http://rai)idfire.sci.ssfc.nasa.gov/subsets/?subset=AERONET Mauna Loa Sept.2008 AS-4 Hawaii County Multi-Hazard Mitigation Plan