## 4 Discussion
Microorganisms including bacteria and archaea that have potential for extensive bioremediation activities are frequently found in landfills and/or dump sites [49; 50]. Bacterial taxonomic distributions in this study revealed that the most dominant phyla across the samples were _Actinobacteria_, _Proteobacteria_, and _Firmicutes_. Numerous studies have found that the phyla _Proteobacteria_, _Firmicutes_, and _Bacteroidetes_ are prevalent in anaerobic ecosystems such as aquifer sediment [51], river sediment [52], and wastewater bioreactor [53] as well as landfills [54]. Furthermore, some studies have indicated the dominant presence of _Firmicutes_, _Proteobacteria_, and _Bacteroidetes_ in various maturing landfills [55; 56; 57; 50]; however, in the present study, we identified phylum _Actinobacteria_ as the most dominant from the collected dump site soils, with the exception of ID1 (Figure 1A). This could indicate that most informal dump sites are not mature enough to have _Proteobacteria_ or _Firmicutes_ dominate over _Actinobacteria_. In addition, the breakdown of organic matter, which is a part of carbon turnover, is the primary activity of _Actinobacteria_[54; 58]. Because dump sites receive waste from a wide range of sources, the amount of organic matter in the soil could be a factor in their presence in informal dumping soil. Not surprisingly, _Actinobacteria_ are also important in the recycling of refractory biomaterials by decomposing complex polymer mixtures in dead plants and animals as well as fungal materials [59]. Next to _Actinomycetes_, the phylum _Proteobacteria_ was the most abundant in all samples, suggesting that _Proteobacteria_ may play a pivotal role in the degradation and assimilation of both organic and inorganic substances respectively, including heavy metal contaminants in dump site soil [49]. Dump site soils also harbored _Chlorofleri_, _Acidobacteria_, _Planctomycetes_, _Bacteroidetes_, and _Gemantiimonadetes_, among other bacterial phyla. _Chlorofleri_ bacterial members are assumed to play a major role in the environment by fermenting carbohydrates and degrading other complex polymeric organic compounds to low molecular weight substrates, which are used by other bacteria for growth [60]. _Bacteroidetes_ are gaining attention for use in bioconversion industries along with _Actinobacteria_, _Firmicutes_, and _Proteobacteria_ because they grow quickly on laboratory media and biodgrade biomass efficiently [61]. Phylum _Gemantiimonadetes_ only has one described member, _Gemantiimonas aurantiacus_, a Gram-negative aerobic heterotroph isolated from sewage [62]. Previous studies have found the highest relative abundance of _Gemantiimonadetes_ near neutral pH [63; 64], which is consistent with our findings. Nonetheless, there is still much to understand about the diversity of this group. The genus level analysis revealed that each sample had a distinct dominant genus. For example, the _Alphaproteobacteria_ genus _Microviga_, found predominately in soil sample ID1, has the ability to oxidize arsenite [65]. Similarly, the genus _Actinoplanes_ is native to a wide range of habitats and is thought to play a role in the turnover of chitin, cellulose,and lignin [66]. Other genus including _Skermanella_ and _Marmoricola_ from sample ID1 have demonstrated high resistance to heavy metals [67], but their biotechnological potential remains elusive. It was not surprising that _Pseudomonas_ dominated the sample collected from the automobile dumps (ID2), which is consistent with other studies [68; 69]. It is reasonable to hypothesize that the _Pseudomonas sp._ from these locations could be an essential component in the bioremediation of environmental settings that have been contaminated by oil and grease. _Rhodococcus_ and _Nocardioides_ were the most common genera in the ID2 sample, followed by _Gordonia_. All of these members are phylogenetically close relatives, and their ability to degrade environmental pollutants has recently attracted greater interest from the biotechnology industry [70].