Hazards of Toxic Tides in Sukinda Valley | S N Tripathy

Odisha, India, holds a prominent status as the leading global producer of Chromite Ore, accounting for nearly 98 % of the world’s supply, with most of its reserves concentrated in Keonjhar, Cuttack, and Dhenkanal. Moreover, the state is celebrated for its extensive mineral resources, including coal, iron ore, manganese ore, and bauxite.

Chromite, a pivotal industrial mineral, plays a vital role in stainless steel production due to its high melting point. Its exceptional properties, including corrosion resistance and versatility, render it indispensable in metallurgical, chemical, and refractory industries, thus driving industrial growth and innovation. Sukinda Chromite Mine, a part of Tata Steel Limited, is in the district of Jajpur, Odisha. It is well-connected to various transportation hubs. The mine is linked to the Jajpur Keonjhar Road Railway Station, situated on the Howrah-Chennai trunk line of East Coast Railways, and a 52 KM all-weather road facilitates this connection.

The J K Road Railway Station is located 336 KM from Tatanagar Railway Station, accessible via Kharagpur, and it is 337 KM away from Howrah. Additionally, the mine is 100 KM from Bhubaneswar, the state capital, and 156 KM from Paradip, the nearest major port on the Eastern Coast. The all-weather road that links Sukinda Chromite Mine to JK Road Railway station intersects NH-200 at Mangalpur, located 21 KM away, and Express Highway No. 1, which connects Daitari to Paradip at Duburi, situated 32 KM from the mine. This strategic location and transportation connectivity enhance the accessibility and logistical advantages of the Sukinda Chromite Mine.

The residents of Sukinda Valley in the Jajpur District encounter significant human health hazards due to environmental contamination. The situation is alarming, with a population of over 50,000, primarily farmers heavily reliant on the Brahmani River and Damsala Nala for their daily needs.

The high concentration of Hexavalent Chromium in the water sources poses severe health hazards to the residents of Sukinda Valley. Hexavalent Chromium is known to cause respiratory problems, skin irritation, and even an increased risk of cancer in humans. The contamination of the Brahmani River and Damsala Nala affects drinking water quality, leading to potential widespread health issues for the entire community. Moreover, using wet drilling arrangements with inadequate dust extraction systems may release harmful airborne particulates, leading to respiratory ailments and other health problems for the mine workers and nearby residents.

The Odisha State Pollution Control Board (OSPCB) conducted an inspection of the South Kaliapani Chromite Mines (SKCM) operated by the Odisha Mining Corporation (OMC) in 2017. The goal was to assess the status of the upgraded Effluent Treatment Plant (ETP). According to the OSPCB’s analysis report, the Hexavalent Chromium (Cr+6) concentration at the outlet of the ETP and other parameters like pH and TSS values were within prescribed standards. However, it was also found that after treatment, the water discharged into Damsala Nalla contained higher than permissible levels of Hexavalent Chromium Cr+6, a highly toxic form of chromium.

In response to the show cause notice issued by OSPCB based on the inspection report, SKCM claimed they would complete the necessary construction by May 2020 and implement measures to prevent water from going beyond the lease area. However, this response did not adequately address the existing contamination and potential risks to human health.

In a subsequent inspection report in 2020, OSPCB observed that SKCM violated the conditions of consent to operate. The mine’s fully mechanized opencast operations and drilling practices, including a wet drilling arrangement with water injection for dust suppression, contributed to environmental pollution.

The research paper employs a secondary sources of data collection, encompassing the accumulation of historical and current data related to South Kaliapani Chromite Mines (SKCM) and the Odisha Mining Corporation (OMC), along with information on environmental violations, consent orders, and regulatory actions.

Findings of the study:

The illegal discharge of wastewater by the South Kaliapani Chromite Mines (SKCM), operated by the Odisha Mining Corporation (OMC), has precipitated dire consequences for human health and the environment. This heedless release of untreated or inadequately treated water has wrought extensive havoc upon private and public properties, causing substantial damage and disruptions to aquatic habitats, profoundly disturbing the stream channel’s natural balance, and adversely impacting the entire ecosystem.

In flagrant disregard of a consent order, SKCM and OMC persist in their extraction and discharge of wastewater from the Sukurangi Chromite Mines area to unauthorized locations that extend well beyond the specified limits, thus implicating both companies in the resultant environmental and health repercussions. Hexavalent Chromium, an exceedingly toxic metal prized for its anticorrosive properties in various industrial applications, is found among the gravest pollutants found in this discharged water. The opencast mining process generates significant overburden, precipitating the leaching of Hexavalent Chromium into the shallow, semi-confined aquifer, which is a vital source of groundwater for the valley, rendering it distressingly susceptible to contamination.

The presence of Hexavalent Chromium exceeding the permissible limit of 0.05mg/l presents a substantial threat to the groundwater regime and the overall environment, raising legitimate concerns about the potential health risks faced by the residents of Sukinda Valley. Furthermore, the absence of an Effluent Treatment Plant (ETP) at the Sukurangi Chromite Mines exacerbates this issue, leading to the uncontrolled transfer of their untreated wastewater to SKCM, thereby creating an environmentally hazardous milieu that places not only the entire Sukinda Valley at risk but also endangers its delicate ecosystem.

The unregulated actions of OMC, which flagrantly violate environmental norms and the consent to operate order, have inflicted severe damage upon the riverbed, socio-economic life, and biodiversity in the region.

Table 1: Environmental Impacts of Chromite Mining in Sukinda Valley

Source: Tripathy and Mishra (2023)

Table 1 summarizes the environmental impacts of chromite mining in Sukinda Valley, outlining the causes and consequences of various issues, including contamination by hexavalent chromium, dust generation, overburden problems, loss of biodiversity, human health risks, and water pollution. Illegal mining and excessive groundwater extraction have led to significant human health and environmental hazards, demanding immediate attention and action. The reduction in groundwater levels is a serious concern that can lead to water scarcity, affecting the well-being and livelihoods of the residents.

Surface water contamination in the core zone can arise from various sources, including mine water discharge, COB Plant runoff, workshops, garages, and rainwater overflow from stacks. Percolation rates fluctuate seasonally, increasing during the monsoon, and are expected to rise with future mining activities. Mine discharge water serves multiple industrial functions, including haul road spraying, HEMM washing, plantation, and COB plant use, with the remainder treated before being released to fallow land.

Water analysis often reveals hexavalent chromium concentrations in mine discharge water exceeding permissible limits. To address this, the company commissioned M/s National Environment Engineering and Research Institute (NEERI) for feasibility studies on hexavalent chromium removal, establishing three effluent treatment plants. One ETP treats mine discharge water, while the other two handle monsoon runoff. Treated water consistently complies with permissible limits. Workshops and HEMM cleaning water are managed with oil and grease traps, and COB plant water is recirculated, not discharged. Rainwater from overflow is treated for suspended solids before release into the natural drainage system.

Prevailing wind directions influence air quality and generally exhibits low average wind speeds. Air pollutant levels in the immediate buffer zone resemble those in distant areas and remain well below CPCB standards. Existing mining operations produce minimal air pollution confined to the core zone. Dust generated by mining and transport machinery, including SO2, NOx, CO, Pb, and HC emissions, is closely monitored and maintained within stringent standards to mitigate fuel emissions. Blasting operations are conducted using controlled techniques while drilling, blasting, and excavation activities are managed with wet drilling, water sprinkling, and regular emission level monitoring. Dust-related issues are negligible in the COB Plant due to wet processes. Future underground mining operations are anticipated to reduce ambient air pollution further.

Mining activities, spanning land acquisition and reclamation, directly and indirectly impact vegetation and fauna. These effects can manifest as short-term or long-term disruptions, affecting the ecosystem, habitat, food chain, and indigenous species. In the core zone, mining initiation in 1960 resulted in the loss of meagre vegetation, primarily shrubs and bushes, with additional forest land utilization projected for overburden dumping.

In the extensive history of the Sukinda Chromite Mine spanning over five decades, measures are in place to manage solid waste. While mining operations have exposed the area, the topsoil is diligently preserved in a separate storage area before initiating activities in the designated region.

This topsoil is meticulously organized in a dedicated 1-meter-high topsoil dump, which is maintained by planting grass on the slopes and atop the dump.

Environmental sustainability is paramount in the mining process, with all overburden waste dumps designed to have a maximum slope of 28 degrees. After mining activities conclude, inactive dumps undergo biological stabilization through multi-species afforestation. The annual overburden generation for the planned five-year period is outlined in Table 2.

Table 2: Sustainable Overburden Management and Afforestation

Source: TATA Steel Limited

Table 2 presents data on overburden generation and its management over six years. Overburden refers to the material, typically soil and rock, that is removed to access mineral deposits beneath. Over six years, 34,996,598 lakh cubic meters of overburden were generated, with the most noteworthy annual output recorded in 2017-18, totaling 6,871,362 lakh cubic meters. A significant proportion of this overburden, equivalent to 7,765,149 lakh cubic meters, was allocated for disposal at the Kakudia Dump, mainly concentrated in the initial year of 2012-13, indicative of the creation or expansion of the Kakudia Dump facility.

The remaining overburden, accounting for 27,231,449 lakh cubic meters, was designated for backfilling in OB-II Quarry. Backfilling involves using excavated material to refill a quarry, often as part of concurrent reclamation and rehabilitation efforts.

The comments associated with this data highlight our commitment to synchronizing environmental and land reclamation efforts with ongoing mining operations. We will initiate concurrent reclamation and rehabilitation actions once the designated disposal and backfilling areas are at capacity.

Suggestions:

Urgent implementation of environmental management systems and early impact regulation strategies is imperative to tackle contamination from mining, groundwater pollution, and illegal wastewater discharges, safeguarding the environment and public health in the vital chromite mining region.

There is an imperative need to undertake the following measures:

i) Besides conventional methods, exploring advanced remediation techniques like phytoremediation and electrocoagulation can be beneficial. Phytoremediation involves using plants to absorb and detoxify hexavalent chromium, while electrocoagulation uses electricity to remove contaminants from wastewater, offering more efficient and sustainable solutions.

ii) Bacterial Remediation: Further research and application of bacteria with high hexavalent chromium reduction potential, such as this can enhance the efficiency of chromium conversion and reduce the environmental impact, especially in areas where bacterial activity is naturally limited.

iii) Strengthening the enforcement of environmental regulations is crucial. This includes cracking down on illegal mining and unauthorized groundwater extraction, regularly monitoring and surveilling mining activities, and implementing strict penalties for non-compliance.

iv) Before initiating any mining project, conducting thorough EIAs is essential. These assessments should evaluate the potential environmental impacts and propose mitigation measures. This proactive approach can help prevent and address contamination issues from the outset.

v) Moreover, public awareness campaigns should inform local communities about the risks associated with hexavalent chromium and promote sustainable mining practices. Collaborative efforts among government agencies, mining companies, environmental organizations, and local communities are essential to ensure the long-term conservation of biodiversity and sustainable development in Sukinda Valley. It is recommended that the Human Rights Commission issue directives to the state government to prioritize these measures for the well-being of the ecosystem and the people in the region.

References:

Tripathy, S.N., & Mishra, Rabi Narayan (2023, August 3). Unearthing Danger: The Sukinda Valley Mines and Their Menace to Society. The Deccan Chronicle. Bhubaneswar.

(Author: Prof S. N. Tripathy, is Former Professor of Economics, Gokhale Institute of Politics and Economics, Pune, currently at Berhampur, Odisha)