ustxtxb_obs_1982_12_10_50_00014-00000_000.pdf

Page 1

by

A Question of Quality To those of us who are not scidata on PCB’s, DDT, fecal coliform, nutrients, and salinity slide by almost surreptitiously like public notices in the back pages of newspapers. We had better pay attention. Water supply is affected by water quality: if water is unsafe for human use, more water must be found \(assuming that people want What’s in our water determines what can live in and around it \(in algae, and plants. And what’s in our water affects us whether we swim in it, drink it, eat fish from it, do laundry with it, or irrigate with it. In its natural state, water is not always safe for human consumption. \(Remember being told only to drink from running streams in the fect water composition. If a stream passes over particular minerals, the water may have a high mineral concentration. Also, natural variations in temperature may occur. When human populations move in, though, and depend on the availability of water, the water quality becomes more crucial and threatened. By using and living around the water, we put stress on water systems: we build on the land over aquifers, dump wastes into rivers and reservoirs, use water for industry, and swim and boat in lakes and rivers. In the late 1960’s, water pollution awareness prompted the passage of the Federal Water Pollution Control Act as well as the creation of the Texas Water Quality Board \(now part of the Texas Dept. of TDWR inventories Texas surface water, monitors water quality, grants effluent discharge permits, looks for the sources of pollution, and requires pollution control mechanisms when water quality standards are violated. Violators can be fined $25,000 a day by the EPA and $1,000 a day by Texas. Parties who discharge an effluent By Amy Johnson must have received a dual permit from the EPA and the TDWR; the permit specifies the amount and type of effluent acceptable, taking into account the particular water affected and its uses. Texas has some water standards that are more stringent than the federal ones, and the state follows other EPA guidelines. Under Reagan those federal standards are being weakened and are going unenforced. This puts an onus on the state. Texas has the structure with which to respond, but even the TDWR has problems with sufficient money and staff. Potential budget constraints have forced the TDWR to ask the Texas river authorities to help monitor water quality in their jurisdictions. As the federal government steps out of the enforcement role, the TDWR will emphasize inspection of new facilities and chronic noncompliant dischargers while inspecting consistently compliant dischargers less frequently. Water pollution does not always create a hazard to public health; rather it impairs the use of the water. Water pollution is either point source \(i.e., a specific point source \(e.g., agriculture, face water segments tested in 1982, 242 were effluent limited, meaning they were in compliance or projected to be in compliance after treatment by industry or municipalities. The other 69 segments were water quality limited, meaning there were significant violations of applicable standards, effluent limitations not stringent enough for the waters to meet the standards, or advanced municipal point source treatment necessary. Seven water-quality parameters determine whether water is acceptable for particular use and whether life in and around the water is being threatened. The seven tests monitor levels of dis solved oxygen, chlorides, sulfates, total dissolved solids, and fecal coliform as well as temperature and pH variances. Deviation from a standard due to natural causes is not considered a violation of the water quality standards. Other tests determine physicochemical measurements of water and sediment, including heavy metals, trace organics, and pesticides. Tests also monitor the condition of the biological community. Dissolved oxygen in the water is consumed by aerobic bacteria, aquatic plants, invertebrates, and fish. As the nutrients in the water increase \(usually due to wastewanumber of aerobic bacteria increases. Those bacteria can consume oxygen resources that sensitive aquatic organisms need. The process whereby aerobic bacteria, algae, then anaerobic bacteria become dominant occurs naturally as lakes age, although very slowly. The introduction of human wastes speeds up this process exponentially. The EPA warns, “The aesthetic qualities of water require sufficient dissolved oxygen present to avoid the onset of septic conditions with their attendant malodorous emissions.”‘ In other words, the water will smell and look like a sewer. Fecal coliform bacteria are found in the wastes of warmblooded animals, originating in the intestine. The fecal coliform test indicates the potential presence of bacterial diseases in the water. Because water has coliforms means that there are probably pathogens present. The pH levels of water test its acidity or alkalinity. In polluted waters, a slight change in pH may greatly affect the toxicity of certain pollutants to fish. A slight decrease in pH may make metals, cyanides, and sulfides more toxic. An increase in pH may make ammonia more toxic. Chlorides and sulfates are inorganic anions \(they have a negative Chlorides are more toxic than sul 14 DECEMBER 10, 1982