Labs - DEC General Chemistry

A - Z Index | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z| En Español|

Labs DEC General Chemistry

Shahla Ameli — Supervisor

Purpose

The GENERAL CHEMISTRY SECTION provides analytical and technical services in the testing of samples for physical and aggregate properties, non-metallic inorganic compounds and organic aggregate constituents to help determine the suitability of drinking water for human consumption, effectiveness of wastewater treatment systems, and the quality of the Chesapeake Bay and its tributary waters. It also analyzes samples suspected of having toxic or hazardous effects. The testing is performed using a variety of state of the art instruments. This section also measures the Biochemical Oxygen Demand and chlorophyll content of water collected from the Chesapeake Bay and its tributaries. The chlorophyll content of water is an important indication of the activity of algae and other organisms whose growth has harmful effects on water and wildlife.

Instrumentation

• Lachat 8000 and 8500 series FIA

• Mantech PC Titrate
• Shimadzu Spectrophotometer
• Shimadzu Spectrofluorophotometer
• Mantech AutoMax BOD Analyzer
• Shimadzu TOC-V Analyzer
• Hach 2100AN Turbidimeter
• Distillation apparatus for phenol
• Spe-Dex 300 for oil and grease
• Exeter CE440 Elemental Analyzer

CE 440 Elemental Analyzer

Mantech Liquid Handler	TOC –V Analyzer

Elements Routinely Analyzed

Tests are performed using a variety of wet chemistry instrumentations. Testing techniques covered in this section include:

TEST / MATRIX	CONTAINER	SAMPLE SIZE	Preservation	PRESERVATION	METHOD
Alkalinity	Plastic	500 mL	4° C	14 days	APHA/
Alkalinity	Plastic	500 mL	4° C	14 days	SM 2320 B
B.O.D.	Plastic	1000 mL	4° C	48 hours	EPA 405.1
T.O.C.	Plastic	500 mL	4° C pH < 2	28 days	EPA 415.2
Chloride	Plastic	500 mL	None	28 days	EPA 325.2
Chlorophyll	Filter	na	- 20° C, Dark	30 days	EPA 10200
Color	Plastic	500 mL	4° C	48 hours	EPA 110.2
Conductance	specific Plastic	500 ml	4° C	28 days	EPA 120.1/
Conductance	specific Plastic	500 ml	4° C	28 days	SM 2510
Cyanide, Amenable	Plastic	500 mL	NaOH,	14 days	EPA 335.1
Cyanide, Amenable	Plastic	500 mL	pH >12	14 days	EPA 335.1
Cyanide, Total	Plastic	500 mL	NaOH,	14 days	EPA 335.2
Cyanide, Total	Plastic	500 mL	pH >12	14 days	EPA 335.2
Fluoride	Plastic	1L	None	28 days	APHA/
Fluoride	Plastic	1L	None	28 days	SM 4500-FC
MBAS (detergents)	Plastic	500 mL	4° C	48 hours	EPA 425.1
Oil and Grease	Glass, Teflon cap	1 L	4° C	28 days	EPA413.1/1664
Oil and Grease	Glass, Teflon cap	1 L	H2SO4, pH <2	28 days	EPA413.1/1664
pH soil	Glass	8 oz	4° C	Immediately	EPA 150.1
Phenol	Glass Teflon cap	1L	4° C4° C	28 days	EPA 420.1
Phenol	Glass Teflon cap	1L	H2SO4, pH <2	28 days	EPA 420.1
Solids
(residue)
Dissolved	Plastic	500 mL	4° C	7 days	EPA 160.1
Total Suspended	Plastic	500 mL	4° C	7 days	EPA 160.2
Settleable	Plastic	500 mL	4° C	48 hours	EPA 160.5
Total	Plastic	500 mL	4° C	7 days	EPA 160.3
Volatile	Plastic	500 mL	4° C	7 days	EPA 160.4
Sulfate	Plastic	500 mL	4° C	28 days	EPA 375.2
Total Petroleum Hydrocarbons	Glass	1 L	4° C	28 days	EPA 1664
			H2SO4 or
			HCl, pH <2
Turbidity	Plastic	500 mL	4° C	48 hours	EPA 180.1

Proper measurement techniques, calibration, verification, and troubleshooting strategies for each parameter are addressed and good laboratory practices are emphasized.

Potential Health Concerns and Environmental Concerns

Chemical analyses determine the suitability of drinking water for human consumption, effectiveness of wastewater treatment systems, and the quality of the Chesapeake Bay and its tributary waters. It also analyzes samples suspected of having toxic or hazardous effects.