2-22. MAINTENANCE AND EFFICIENCY
a. Maintenance. Although package plants are designed for simple operation,
they are by no means maintenance free. A qualified operator should be assigned to
perform necessary maintenance and tests. Normal maintenance includes checking
equipment for proper operation, lubricating, cleaning, housekeeping and
groundkeeping, maintaining supplies, and washing off excess residue (sludge). Simple
tests to determine the efficiency of the plant may include analysis for residues, residual
chlorine, and pH.
b. Efficiency. When properly operated, package plants can be as efficient as
large treatment plants. Removal of up to 90 or 95 percent of nonfiltrable residue can be
Section VII. OPERATIONAL TESTS AND SAMPLING
2-23. OPERATIONAL TESTS
The purpose for the principal tests conducted in a conventional wastewater
treatment plant and the significance of each is Iisted below. However, the list is not all-
inclusive. The discharge permit from the governing Federal, state, and local regulatory
agency will specify the tests that are to be conducted. Details of the conduct of each
test are a technical subject beyond the scope of this subcourse.
a. Purpose of Tests. Wastewater is sampled and analyses are made to:
Determine the overall efficiency of the treatment process.
Control the various wastewater treatment processes.
Predict effects at the point of final disposal.
Determine actual results of treated wastewater discharge.
Verify compliance with appropriate discharge permit.
Compile records and data for future use.
b. Residues. Determination of the residue content of wastewater at various
points in the treatment process indicates the efficiency of removal during various
individual treatment processes. The residues in wastewater are in suspension and in
solution. Grouped together, nonfiltrable residues and filtrable residues comprise the
total residues. The nonfiltrable residues consist of settleable residues and
nonsettleable residues. Most of the nonsettleable residues are very finely divided. The