Washington State Uni LIST: Perennials for septic field

After scanning the threads on this topic here, I am still not sure what to do with a septic leach field. The county has ideas including some things I recognize (I am not copying out their list of herbaceous annuals...can't imagine spending time working on the decor of a leach field). Has anyone had experience with any of these? What else would you add?:

Herbaceous perennials
America, Seathrift (Armeriac maritima)
Astilbe (Astilbe x arendsii)
Basket of gold (Aurinia saxatilis)
Campanula (Campanula spp)
Snow in summer (Cerastium tomentosum)
Lily of the Valley (Convallaria majalis)
Sweet William (Dianthus barbatus)
Cottage (et al) Pinks (Dianthus spp)
Coral Bell (Heucheria sanguinia)
Candytuft (Iberis sempervirens) evergreen
Lavendar (Lavenduia angustifolia) evergreen
Moss pink (Phlox subulata)
Heather (Calluna vulgaris)
False Lily of the Valley (Maianthemum dilatatum)

Perennial Ground Covers
Carpet bugle (Ajuga reptans)
Kinnickinnick (Arctostaphylos uva-ursi)
Irish moss (Arenaria verna)
Bunchberry (Cornus Canadensis)
Twinflower (Linnaea borcalis)
Wintergreen (Gaultheria procumbens)...I have some of this but it should not be planted in full sun
Salal (Gaultheria shallon)
Lydia broom (Genista Lydia)
Pachysandra (Pachysandra terminalis) *shaded only*
Stone crop (Sedum spp) ... I have some Oregon Stone Crop, tastes like purslane but crunchier
Hens and chicks (Sempervirum tectorum)
Periwinkle (Vinca minor)
Thyme (Thymus spp)

Fredy Perlman wrote: What else would you add?

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