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SCHEMATIC OF A TWO STAGE LAGOON DAIRY OPERATION
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Note: Waste from dairy cows is collected in primary lagoon, where most solids
settle to bottom. Wastewater is then sent to a secondary lagoon for further treatment. Finally, after further settling of solids, wastewater is used to irrigate
crops. Contamination may occur from improper irrigation techniques, from heavy rains which cause lagoons to overflow or from leaching of wastewater below the
ground.
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Souce: Texas Agricultural Extension Service, Texas A & M
University, College Station, Texas.
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Agricultural activity accounts for many of the reported cases of non-point-source pollution in
Texas's impaired rivers, streams, bays and estuaries.* The irrigation of crops, the application of fertilizers to pasture or range
land, and the use of hihgly concentrated feedlots all generate such non-point-source pollutants as plant nutrients, pesticides, sediment, and animal wastes. Either through
seepage into groundwater --eventually connecting to surface water -- or run-off associated with rainfall, all of these can potentially impact surface water.
Major contributors of non-point-source pollution are CAFOs (confined animal feeding
operations), facilities that house animals used for the production of eggs, milk, and meat. CAFOs generate a variety of
potential pollutants. Animal wastes contain pathogens, chlorides and potassium salts, and high levels of nitrogen.
CAFOs may degrade state waters by increasing nutrient loads and fecal coliform in many rivers. This type of
contamination ultimately lowers dissolved oxygen levels, which threatens the viability of aquatic habitats and consequently the use of the river for fishing, swimming, or drinking.
State regulations now prohibit these facilities from discharging wastewater or animal waste directly into streams and
rivers. Operators must also not allow the waste to run off the site, where it could contaminate surface water or
groundwater. Currently, every large CAFO must obtain a no-discharge permit from the state, which requires that the
facility control runoff except when there is excessive rain. Many large cattle operations are located in the Panhandle,
while dairy-farm operations are concentrated in Erath County, near Stephenville. In fact, there are an estimated 180
dairy CAFOs in the Bosque and Leon watersheds, permitted to contain over 130,000 head of cattle, producing an
estimated 1.8 million tons of manure annually. Currently, there are over 575 permitted CAFO facilities statewide* as
well as several thousand smaller facilities that do not require a permit. In 2001, the Texas legislature passed legislation
which allowed the TCEQ to adopt more stringent permit requirements for larger dairy CAFOs in the Bosque Watershed,
in and near Erath County, because of the wide-scale pollution problems there and concerns about the resulting pollution
both in the Bosque and Leon Rivers -- listed as impaired because of high levels of nutrients and depressed dissolved
oxygen levels -- and even downstream in Lake Waco, which serves the City of Waco with its drinking water, and has experienced algae glooms from excess nutrients*.
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FYI
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An average open feedlot receives about 300 tons of manure containing 24,000 pounds
of nitrogen per acre per year. By contrast, animals on typical open rangeland deposit about 1/10 of a ton of manure containing eight pounds of nitrogen per acre
per year.*
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In 1993 the Texas legislature transferred much of the responsibility for
regulating non-permitted, smaller CAFOs from the then-TNRCC to the Texas State Soil and Water Conservation Board. The move was designed to
change the state's oversight of these operations from a traditional regulatory role to a technical assistance role. Even the smaller
non-permitted CAFO are expected to comply with the no-discharge policy. The state can initiate an enforcement action on these facilities if they
discharge into the state's waters.The Soil and Water Conservation Board, with assistance from the TCEQ, is attempting to help agriculture adopt better
runoff control practices, mainly through waste management plans, allowing the facilities to come into compliance voluntarily. Currently, the Dairy
Outreach Program is implemented in both North-Central Texas, in a five-county area, and in East Texas, in a three-county area.* A particular concern, however, is that as enforcement and permit requirements have increased in
North Texas, a number of existing and new Dairy CAFOs appear to be heading to West Texas, where inspections, enforcement and permit requirements are generally less rigorous.
Other Agricultural Non-Point-Source Pollution
Apart from CAFOs, agricultural lands may contribute other sources of non-point-source pollution. Runoff from croplands
may dump fertilizers and pesticides into surface waters. Runoff from rangeland often contains eroded soil, which
causes sedimentation of rivers and streams. Such runoff may also contain high concentrations of nitrogen and
phosphorus from animal waste and fertilizers. In Texas, from 1968 to 1990, 470 out of nearly 55,000 samples of
surface water tested for nitrates exceeded the recommended drinking water standard of 10 milligrams per liter.
Though this overall rate of violations is low—less than 1 percent—the problem samples were concentrated in a handful
of counties, indicating a potentially serious regional problem with nitrate contamination.*
Surface water in Texas has not been extensively monitored for pesticides. However, arsenic, which is used in some
pesticides, has been identified in several counties as a surface water concern. About five percent of total samples taken
by the state between 1968 and 1990 exceeded the drinking water standard of 50 micrograms per liter for arsenic.
Since arsenic occurs naturally and is also an industrial pollutant, it is difficult to pinpoint the source of arsenic in surface
water. Most of the samples that exceeded standards were collected in counties with high industrial activity as well as agricultural production.*
Enforcement and Compliance of Agricultural Surface Water Pollution
In part because of the voluntary compliance agreement with the State Soil and Water Conservation Board, the TCEQ
does not issue as many orders for agricultural water quality violations as it does for industrial and domestic water
quality violations. Still, as attention has focussed on some of the water quality problem associated with agricultural
facilities, and as political leaders -- particularly in the Bosque and Leon Watersheds -- have brought attention to impacts
on city drinking water, more enforcement has occured. Total inspections of agricultural facilities -- mainly CAFOs --
rose from about 760 in FY 1996 to 1,098 in FY 99, but then fell to 589 in FY 01.* The number of facilities issued Notices
of Violations fell between FY 96 and FY 99 -- from 307 to only 15, but has risen again, topping 200 in FY 01. Between
FY 96 and FY 01, the then-TNRCC issued 98 administrative orders and assessed penalties of $750,000, although more
than $200,000 of this total was deferred under agreements with the agricultural operators.* Most of these enforcement
cases were related to unauthorized discharge of wastewater from CAFOs.*
Within the five-county Dairy Outreach Program area (in the Bosque and Leon Watersheds), the TCEQ has a policy to
inspect every permitted facility. In this region, the then-TNRCC increased inspections from 169 in FY 1996 to 445 in FY
1999, before inspections declined to 216 in FY 2001. From both these annual inspections, as well as complaint
inspections, the TNRCC issued between 80 and 136 notices of violations on a yearly basis. Administrative orders ranged from a high of 13 in FY 1998 to only two in FY 2001*. Some environmental organizations and political leaders have
called for a more rigorous enforcement program both in the Bosque and Leon Watershed, as well as statewide, due to the continued proliferations of CAFOs in Texas.
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