FAQ's about Environment

The USGS Wildlife: Terrestrial and Endangered Species Program conducts research and monitoring to conserve, protect, and restore declining species and the habitats they depend on. For more information on these activities go to the USGS imperiled species website.

Highlights of new ground-breaking USGS research on endangered plants and animals has just been released in partnership with the U.S. Fish and Wildlife Service in a publication called the Endangered Species Bulletin (PDF).

Trace essential elements such as fluorine, copper, selenium, molybdenum, and others can be hazardous to living organisms if present at high levels. Nonessential heavy metals such as arsenic, lead, mercury, cadmium, chromium are usually toxic to organisms as much lower levels than trace essential elements. Depending on the association that these nonessential elements may form with natural geologic materials such as organic matter, other elements or minerals, and adsorbers (such as clays), these elements can range from being safe to being extremely toxic.

Because of growing public concern about the environmental contamination, it is becoming increasingly important to better understand both the natural and human processes that control the movement of elements at the Earth's surface. Elements can be quite mobile in water, and the majority of our environmental problems are ultimately associated with the contamination of surface and ground water.

When water comes into contact with rocks and soils, some of the minerals and organic substances dissolve and enter the natural waters. Forests and grasslands generally contribute only small amounts of these dissolved substances. However, it is possible for an area to contain unusually high concentrations of minerals, thereby depositing them to the waterways. For example, swamps and marshes often produce acidic and colored water. Other areas that contributed natural pollutants to water are those containing rocks with sulfide minerals, particularly pyrite.

Inorganic substance are cycled naturally through our environment at concentrations that usually do no adversely affect plants and animals. However, the combination of some natural processes with human activities can increase these substances to harmful or toxic levels. Therefore, toxic substances may have both natural and human sources.

Natural sources of toxic substance include rocks, volcanoes, sediments, and soils. Human activities that add toxic substances to the environment include smelting, manufacturing, refining, chemical processing, fertilizer application, irrigation, and waste disposal.

A large concentration of a substance commonly identifies a source of pollution but may not necessarily indicate a problem. In addition to the concentration, other characteristics of the substance must be considered. These characteristics include the amount of the substance released, the rate of release, its availability to organisms, and its residence time in a particular ecosystem. (From USGS Circular 1105.)

To accomplish these tasks, the USGS has over 150 field offices where personnel are involved in the following activities:

They are primarily algae feeders. They feed by filtering the water through a siphon, up to a liter per day. This is why they like the insides of pipes so well, there is a constant supply of water and food flowing by them.

The U.S. Geological Survey (USGS) recently completed an assessment of our Nation's geothermal resources. Geothermal power plants are currently operating in six states: Alaska, California, Hawaii, Idaho, Nevada, and Utah. See Fact Sheet 2008-3082 "Assessment of Moderate- and High-Temperature Geothermal Resources of the United States".

Iceland also makes great use of its geothermal resources.

The Gap Analysis Program (GAP) is a state-based cooperative effort to map major indicators of biodiversity over states, along with the existing network of conservation lands. The indicators of biodiversity that the GAP state projects map using geographic information system (GIS) technology are dominant vegetation types (e.g., oak-hickory-hemlock forest) and distributions of each native vertebrate species.

Although coordinated by the BRD, the program is made up of over 400 cooperating organizations nationwide, including businesses, governments, and universities.

The current El Niño will probably surpass the greatest El Niño of century, that of 1982-83. During the past 40 years, nine El Niños have affected the western coasts of North and South America. Most of them raised water temperatures along 5000 miles of coast. The weaker events raised sea temperatures only a few degrees Fahrenheit and caused mild changes in weather. But the strong ones, like the El Niño of 1982-83, left a climatic imprint that was global in extent.

El Niño recurs irregularly, from two years to a decade, and no two events are exactly alike. Before the 1982-83 El Niño event, scientists did not collect detailed information on El Niños, so information is scanty for making high-quality predictions about the effects of the current El Niño of 1997-98.

The impacts of El Niños can be devastating, as illustrated by some of the effects of the unusually strong El Niño of 1982-83:

- Drought (sometimes with associated wildfires) in many nations (particularly in the western Pacific Rim, southern and northern Africa, southern Asia, southern Europe, and parts of South and Central America);- Severe cyclones that damaged island communities in the Pacific;- Flooding over wide areas of South America, western Europe, and the Gulf Coastal states; - Severe storms in the western and northeastern United States.

Ground water, which is in aquifers below the surface of the Earth, is one of the Nation's most important natural resources. Ground water is the source of about 37 percent of the water that county and city water departments supply to households and businesses (public supply). It provides drinking water for more than 90 percent of the rural population who do not get their water delivered to them from a county/city water department or private water company. Even some major cities, such as San Antonio, Texas, rely solely on ground water for all their needs. About 42 percent of the water used for irrigation comes from ground water. Withdrawals of ground water are expected to rise as the population increases and available sites for surface reservoirs become more limited.

Probably. Visit our Geologic Information pages or we will take a look for you.

Go to the Energy Resources website at http://energy.usgs.govfor a newly released gas hydrates assessment of the North Slope of Alaska. A fact sheet is at http://pubs.usgs.gov/fs/2008/3073.

Visit the USGS National Wildlife Health Center (NWHC) web pages at http://www.nwhc.usgs.gov/. The National Wildlife Health Center was established in 1975 as a biomedical laboratory dedicated to assessing the impact of disease on wildlife and to identifying the role of various pathogens in contributing to wildlife losses. Go to http://www.nwhc.usgs.gov/disease_information/ for information about specific diseases being studied by the NWHC.

Water being drawn from a well was once precipitation that fell onto Earth's surface. It seeped into the ground and, over time, occupied the porous space in some subsurface material. Naturally, big particles that can be found in streams, such as leaf chunks, will not be seen in ground water. So, yes, big particles are filtered out. But ground water can contain other items that you can't see. Some are naturally occurring and some are human-made substances. Ground water can contain hydrogen sulfide or other naturally occurring chemicals. Ground water also may contain petroleum, organic compounds, or other chemicals introduced by humans' activities.

Contaminated ground water can occur if the well is located near land that is used for farming where certain kinds of chemicals are applied to crops, or near a gas station that has a leaking storage tank. Leakage from septic tanks and/or waste-disposal sites also can contaminate ground water. A septic tank can introduce bacteria to the water, and pesticides and fertilizers that seep into farmed soil can eventually end up in water drawn from a well. Or, a well might have been placed in land that was once used for something like a garbage or chemical dump site. In any case, it is wise to have your well water tested for contaminates.

Saline water has some uses. In 2000, the U.S. used about 62 billion gallons per day of saline water, which was about 15 percent of all water used. But saline water can only be used for certain purposes. The main use was for thermoelectric power-plant cooling. As for the other uses, about 8 percent of water used for industrial purposes was saline, and about 43 percent of all water used for mining purposes was saline. Also, saline water can be desalinated for use as drinking water by putting it through a process to remove the salt from the water. The process costs so much that it isn't used very much right now.

So, what is a zebra mussel? They are a type of mollusk, which also include a wide variety of organisms such as squids, octopuses, snails, oysters, scallops, and clams. Generally, zebra mussels live for four to five years and average about an inch in length. Mussels are also called "bivalves," which means they have two shells or valves. The zebra mussel gets its name because of the dark, striped pattern on each valve. Usually the shell is a light color, either tan or beige, with zig-zag stripes.

First of all, plants naturally grow in and around lakes. Maybe you're asking about a lake that is being choked off by too much algae. In many cases, humans are responsible. Actually, these lakes are being fed too much food for plants! There are certain chemicals we use that are nutrients (food) to plants. At our homes we fertilize our yards with nitrogen, potassium, and phosphorus. These chemicals wash off our lawns and eventually get into the water system, such as into creeks, rivers, and lakes. Once there, algae and plants have a feast on this "food". Things used to be worse for our water bodies. Phosphorus used to be an ingredient in our laundry detergent, but this has generally been phased out.

Radon is a gas produced by the radioactive decay of the element radium. Radioactive decay is a natural, spontaneous process in which an atom of one element decays or breaks down to form another element by losing atomic particles (protons, neutrons, or electrons). When solid radium decays to form radon gas, it loses two protons and two neutrons. These two protons and two neutrons are called an alpha particle, which is a type of radiation. The elements that produce radiation are called radioactive. Radon itself is radioactive because it also decays, losing an alpha particle and forming the element polonium.

(91 kb)

Elements that are naturally radioactive include uranium, thorium, carbon, and potassium, as well as radon and radium. Uranium is the first element in a long series of decay that produces radium and radon. Uranium is referred to as the parent element, and radium and radon are called daughters. Radium and radon also form daughter elements as they decay.

The decay of each radioactive element occurs at a very specific rate. How fast an element decays is measured in terms of the element "half-life", or the amount of time for one half of a given amount of the element to decay. Uranium has a half-life of 4.4 billion years, so a 4.4-billion-year-old rock has only half of the uranium with which it started. The half-life of radon is only 3.8 days. If a jar was filled with radon, in 3.8 days only half of the radon would be left. But the newly made daughter products of radon would also be in the jar, including polonium, bismuth, and lead. Polunium is also radioactive - it is this element, which is produced by radon in the air and in people's lungs, that can hurt lung tissue and cause lung cancer.

(74 kb) Radon levels in outdoor air, indoor air, soil air, and ground water can be very different.

Radioactivity is commonly measured in picocuries (pCi). This unit of measure is named for the French physicist Marie Curie, who was a pioneer in the research on radioactive elements and their decay. One pCi is equal to the decay of about two radioactive atoms per minute.

Because the level of radioactivity is directly related to the number and type of radioactive atoms present, radon and all other radioactive atoms are measured in picocuries. For instance, a house having 4 picocuries of radon per liter of air (4 pCi/L) has about 8 or 9 atoms of radon decaying every minute in every liter of air inside the house. A 1,000-square-foot house with 4 pCi/L of radon has nearly 2 million radon atoms decaying in it every minute.

Radon levels in outdoor air, indoor air, soil air, and ground water can be very different. Outdoor air ranges from less than 0.1 pCi/L to about 30 pCi/L, but it probably averages about 0.2 pCi/L. Radon in indoor air ranges from less that 1 pCi/l to about 3,000 pCi/L, but it probably averages between 1 and 2 pCi/L. Radon in soil air (the air that occupies the pores in soil) ranges from 20 or 30 pCi/L to more than 100,000 pCi/L; most soils in the United States contain between 200 and 2,000 pCi of radon per liter of soil air. The amount of radon dissolved in ground water ranges from about 100 to nearly 3 million pCi/L.

Why do radon levels vary so much between indoor air, outdoor air, soil air, and ground water? Why do some houses have high levels of indoor radon while nearby houses do not? The reasons lie primarily in the geology of radon - the factors that govern the occurrence of uranium, the formation of radon, and the movement of radon, soil gas, and ground water.

Go to these two websites:

• Sources of Radon Information
• Indoor Air Quality Publications

Not specifically. Our charge is to understand characteristics of the earth, especially the earth's surface, that affect our Nation's land, water, and biological resources. That includes quite a bit of environmental monitoring. Other agencies, especially NOAA and NASA, are specifically funded to monitor global temperature and atmospheric phenomena such as ozone concentrations. Our work at USGS in the Global Change and Climate History Program focuses on understanding the likely consequences of climate change, especially by studying how climate has changed in the past.

A period of below-normal rainfall does not necessarily result in drought conditions. Some rain returns to the air as water vapor when water evaporates from water surfaces and from moist soil. Plant roots draw some of the moisture from the soil and return it to the air through a process called transpiration. The total amount of water returned to the air by these processes is called evapotranspiration. Sunlight, humidity, temperature, and wind affect the rate of evapotranspiration. When evapotranspiration rates are large, soils can lose moisture and dry conditions can develop. During cool, cloudy weather, evapotranspiration rates may be small enough to offset periods of below-normal precipitation and a drought may be less severe or may not develop at all.

Reference: Moreland, 1993, Drought: U.S. Geological Survey Water Fact Sheet, Open-File Report 93-642