TM 5-814-3/AFM 88-11, Volume III
DESIGN AND SAFETY
The goal of any wastewater treatment system is to produce an acceptable effluent that meets all the applicable
standards. This must also be accomplished at a reasonable cost. After the design has been completed, it is up
to the operations and maintenance staff to assure that the system is:
-- Operated properly;
-- Continuously maintained;
-- Run safely; and
-- Monitored to continually plan for improvement in quality, cost savings and safety.
In a report to Congress, the EPA indicated that, throughout the country, wastewater effluent quality
standards have not been met. In many instances, effluent requirements are not being met due to the following
-- Process control is too complex;
-- Equipment operation and maintenance costs are excessive;
-- Maintainability of equipment is not considered in the facility design;
-- Emergency provisions are not included in the facility design;
-- Ease of operator functions are not considered in the facility design; and
-- Inadequate design of materials handling and storage.
Obviously all of these factors are critical in the design of a waste treatment facility. Therefore, it is the
designer's responsibility to always be cognizant of these factors throughout the design phase of a project. In
some cases, this may require early, detailed discussions with the operation and maintenance personnel.
However, the benefits derived from these considerations could mean the difference between a non-compliance
facility and a well-operated facility.
19-2. Specific design considerations.
Some particular areas of design where the factors noted above should be considered:
a. Equipment failures and contingencies. Provisions should be made for standby equipment or bypass
piping for situations whenever process equipment failures are encountered. These conditions should also be
planned for routine maintenance of process equipment.
b. Equipment maintainability. Provisions should
be made for access,
maintenance and removal
process equipment. Simple maintenance functions, such as the removal of pump motors, are often impossible
due to inadequate access space.
c. Ease of equipment operation. All of the unit processes described in this manual have been evaluated
for their ease of operation and consistency of treatment performance. Selection and design of process equip--
ment should also consider these factors. For example, equipment that requires considerable operator attention
should be less favored to simple, operator-free equipment.
d. Ease of operator functions. Stairs, walkways, manways and other structures should be included in
the facility design to enhance the routine functions of the operator. Also, adequate lighting is essential for