Potential water pollution from recycled concrete aggregate material

Abstract

Recycled concrete aggregates (RCA) are a widely used recycled building material. RCA materials have many uses such as a road base or backfilling trenches. Our study investigated the potential water-contamination risks of water exposed to RCA materials. We recirculated water for 60min through four different treatments. Two treatments were a PVC gutter filled with different size grades of RCA material (20mm and 45mm), the third treatment was a clean PVC gutter and the fourth and final treatment was an unused concrete water pipe. Results showed that RCA material exposed to water released a suite of contaminants that could be ecologically hazardous to aquatic species. RCA leached metals over the 60-min recirculation (aluminium, arsenic, barium, chromium, lead, manganese, molybdenum, titanium, lithium and strontium). Water exposed to RCA material exceeded aquatic ecosystem guidelines for aluminium by 50 times and lead by up to 12 times. RCA materials increased pH by up to 4.35 pH units and electrical conductivity (EC) by up to 11 times the starting EC (mean 27.9 µs cm–1). We suggest that RCA materials need to be used with caution in settings that could be exposed to water and flow to waterways of conservation value.

The Influence of Concrete and Urban Water Quality On The Growth of An Invasive Weed (Salix Spp.) in One of Australia’s Most Endangered Aquatic Environments.

“…Water chemistry differed between the four different water treatments at the outset of this study (Purdy et al 2020; Table 1). The four treatments used water obtained from two different BMUS wetlands.…”

Jenis Sarana Dan Kualitas Bakteriologi Sumber Air Bersih Di Desa Bale Donggala Sulawesi Tengah

“…Konstruksi bangunan yang tidak memenuhi syarat tersebut berpotensi sangat tinggi menimbulkan pencemaran terhadap air bersih. Pembangunan bangunan yang tidak memenuhi syarat berpotensi menimbulkan pencemaran terhadap air bersih (Purdy et al, 2021). Kegiatan konstruksi merupakan sumber utama pencemaran, termasuk pencemaran air, karena faktor-faktor seperti pembuangan limbah pembongkaran yang tidak tepat di TPA (Rahman & Ali, 2018).…”

Recirculating Water through Concrete Aggregates Rapidly Produced Ecologically Hazardous Water Quality

“…The swamp and its immediate catchment are naturally vegetated and free of urban development [15]. Water from this swamp has been monitored for several years in multiple investigations and is regarded as being indicative of a near-pristine swamp with sound ecological health [13,15,16,36]. Water emerging from this swamp has the characteristic low pH (<5.8), low EC (<35 µS cm −1 ) and ionic composition domination by sodium and chloride ions that are typical of a pristine THPSS [10,15].…”

“…There were several laboratory leaching studies that examined the leaching behaviour of metals from RCA under different settings [33][34][35]. Based on the potential for short-term exposure (one hour) of runoff to RCA materials in field settings, a short-term recirculation laboratory study evaluated water quality changes [36]. This demonstrated rapid changes in EC and pH and reported increased major ion concentration and increased metal concentrations after 60 min of recirculation.…”

“…We chose to use a wider range of commercial RCA materials of different aggregate sizes to investigate whether the aggregate size influences the nature and scale of water quality modification. In particular, we wanted to test whether RCA materials exposed to water for a realistic amount of time (60 min) resulted in the production of leachate containing environmentally hazardous concentrations of metals and other water quality attributes [26,36].…”