Septic Systems Installation

Guidelines for designing proper performing OSSFs:

1.Flow equalization for all ATU's
2.Pressurized time dosing to field for systems with primary treatment only
3.Homeowner questionnaire
a.No ATU's if not perpetually occupied
4.Use TCEQ flows to establish average daily flows only
a.Use a project-specific peak flow multiplier for design
5.Do not depend on homeowner for success of system.
a.Automatic zone switching
i.verifiable
b.Automatic filter flushing
c.Automatic field flushing
d.Chlorine disinfection only if provider supplying Cl2 monthly
i.Ozone or UV disinfection, otherwise
e.Flow meter to verify system performance and usage
6.Electronic monitoring, if used, must verify system performance between visits
a.Auditable reporting
b.Verify communication integrity, at least monthly
c.Show system performance
i.Historical, at a minimum
ii.Real Time, for commercial
d.Service Provider's performance tracking
7.Commercial/Institutional Pretreatment Required
a.Determine wastewater characteristics
i.Influent
1.BOD, TSS, pH, COD, FOG, Temperature, Toxicity
2.Multiple samples
3.Multiple days
ii.Effluent
1.BOD >140
2.TSS >140
3.FOG > 10
4.pH = 7.0 approx.
b.Determine flows
i.GPM, avg
ii.GPM, peak
iii.GPD, avg
iv.GPD, peak
c.Determine balance of design using steps 1-5.