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Flourometric Dye Tracing
The use of fluorescent dyes and
tracing techniques provides a means of measuring the time of travel of
solutes in steady and gradually varied flow in streams. This
information is needed to determine time of travel for use in
water-quality models and to define relations so that transient
water-quality problems and waste transport studies can predict the
time of arrival and passage time of a hazardous substance released or
spilled upstream. Time of travel refers to the movement of water or
waterborne solutes from point to point in a stream during steady or
gradually varied flow conditions. The measurement or simulation of
time of travel using dye tracers involves the slug injection of a dye
at some location along the stream and the measurement of the resulting
response, or dye cloud, at other locations downstream. When a
fluorescent dye is used as a tracer, the degree of fluorescence can be
determined with a fluorometer. The Model 6700 fluorometer has been
designed based on field and research requirements and particularly
fulfills the need for automatic and real-time on-line monitoring of
dye tracer concentrations. The 6700 has been fully tested under field
conditions by hydrology professionals over the past 8 years. A
double-excitation, double-detection optical scheme permits
simultaneous concentration measurements of two different dye tracers
and water turbidity. Although the optical filter set is selected for
the dye tracer pair uranine-sulforhodamine G, other dyes can be
detected. Thanks to a very favorable separation of their
characteristics in the visible spectrum, uranine and sulforhodamine G
tracers can be used simultaneously at two different injection sites.
The instrument can recover the two overlapping tracing curves with
small mutual interaction of the dyes. Real-time measurement of the
turbidity in the range of 0.02 to 400 nephelometric units is also of
great interest. A flow-through field fluorometer can be put into water
of widely varying quality to measure very small dye concentrations
(0.05 ppb). The fluorometer replaces out-dated and frequently
impractical mechanical sampling systems. There are two 6700 existing
fluorometer models. Both are convenient for direct immersion in
surface waters and require no pump. In addition, the surface model is
also well suited for fast analysis of individual water samples. The
downhole groundwater model can be used in 3" diameter boreholes to a
depth of 160ft. (50 m.) Unattended measurements with a high sampling
frequency can extend over weeks instead of the daily or hourly
sampling of mechanical systems.
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Specifications: |
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Detectable Tracers |
Uranine + Sulforhydrodamine or Rhodamine Wt |
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Number of Signal Channels |
4, including turbidity meas. 0.02 to 400 NTU |
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Detection Threshold |
2 X 10" g/ml (naphtionate 5 x 10" g/ml) |
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Memory Card Sample Capacity |
64KB PCMCIA |
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Recording Time Capability |
10 sec and 4 min. from 14 to 28 days |
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Data Availability |
On PC memory card and at serial RS232 port |
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Power Supply |
12 Volt, 7 to 14 AH Battery |
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Connections |
15 m cable with waterproof connectors |
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Size of Surface Model Sonde |
Diameter 160 mm, Long 170 mm |
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Weight (with datalogger, battery) |
12 kg |
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3" Sonde for Downhole Tests |
Diameter 74 mm, Long 200 mm |
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Item No. |
DESCRIPTION |
WEIGHT |
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110-001 |
Surface Water Fluorometer |
26 lbs. |
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110-005 |
Ground Water Fluorometer |
25 lbs. |
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Visible fluorescent dyes make waterflow patterns
easy to see and track. Ecologically safe dyes for use in stream
tracing, lake studies, flow mapping, time of travel surveys, pollution
studies and leak detection. Two formulations: FWT Red, a specially
formulated version of the dye Rhodamine WT and FLT Yellow/Green, which
is a formulated version of the dye Fluorescein. Fluorescent colors can
be detected visually in most water conditions or with the use of
ultra-violet light or a fluorometer. Fluorescent dyes are temporary
and will degrade naturally in sunlight, 2-3 days for red and 5-7 days
for Yellow/Green, or with the addition of chlorine. FLT Yellow/Green
is resistant to absorption in organic matter and should be used in
water with heavy sediment loads. Available in tablets, cake or liquid.
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Item No. |
DESCRIPTION |
WEIGHT |
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110-010 |
FWT Red, 200 Tablets |
0.8 lb. |
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110-015 |
FLT Yellow/Green, 200 Tablets |
0.8 lb. |
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110-011 |
FWT Red, 2 oz. Cake |
0.8 lb. |
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110-016 |
FLT Yellow/Green, 2 oz. Cake |
0.8 lb. |
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110-012 |
FWT Red, Pint Liquid |
2.0 lbs. |
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110-017 |
FLT Yellow/Green, Pint Liquid |
2.0 lbs. |
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110-013 |
FWT Red, Gallon Liquid |
9.5 lbs. |
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110-018 |
FLT Yellow/Green, Gallon Liquid |
9.5 lbs. |
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Two models of standard A/C or battery-operated
ultraviolet lights for identifying dye tracers are available. The
handheld, Raytector S-2 12W Longwave/Shortwave Lamp features a
wraparound handle designed for comfortable balance. Rugged ABS plastic
and fingertip switches. Its Rechargeable Double Lamp has two 6W lamps
and operates from internal gel-based, lead-acid battery. Recharges
with AC power. Toggle switch selects longwave or shortwave separately
or both at same time. The Versalume light is a lightweight compact
unit that uses four AA batteries or 115 VAC adapter. This is a 4 watt
lamp and is small enough to fit in your pocket with the fold up dual
purpose handle. It weighs one pound and comes with a combination
longwave/ short wave bulb.
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Item No. |
DESCRIPTION |
WEIGHT |
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110-025 |
Raytector S-2 UV Light |
6 lbs. |
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110-026 |
Replacement Longwave Bulb |
0.5 lb. |
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110-027 |
Replacement Shortwave Bulb |
0.5 lb. |
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110-030 |
Versalume UV Light |
1.5 lbs. |
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110-031 |
Replacement Long/Short Wave Bulb |
0.3 lb. |
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206-017 |
Pack of Eight AA Batteries |
0.5 lb. |
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