Tag: sedimentasi lumpur

  • Institute Offers to Plug Mud Leaks

    The 10 November Institute of Technology (ITS) in Surabaya is offering a new solution to control the hot mudflows at the Lapindo Brantas Inc. mining site in Porong and a new way to manage the dumping of mudflow waste.

    The new technology was invented and developed by an ITS team of experts in cooperation with the UN Environmental Program (UNEP) and United Stated Agency for International Development (USAID).

    ITS team leader I Nyoman Sutantra said the technology was based on the Bernoulli Theory.

    It would stop the flows by rerouting the hot mudflow through a dam of pipes of 50 centimeters in diameter and 50 meters in height, each erected right on the source of the flow, he said.

    The flow, he added, would go back down the pipes to be diverted, once it reached their top end.

    “We have conducted research and a series of experiments to analyze the validity of the idea. We are confident this could deal with the mudflow,” he told The Jakarta Post on Monday.

    He said his team, in cooperation with the private sector, was ready to finance the implementation of the solution to control the mudflow that has badly affected local residents and the provincial economy.

    The new technological solution comes following a series of failures of other technologies previously proposed to stop the mudflow, including the insertion of stone balls into the holes and various methods suggested to divert the flow.

    Regarding the method that his team has proposed to deal with the mudflow, Sutantra said it was designed to prevent further destruction of the environment and possible flash flooding during the rainy season.

    The team sees the current handling by the Sidoarjo Mudflow Handling Agency (BPLS) as being not effective enough, since the mudflow is partly dumped into a giant pond and partly diverted into the Porong River.

    This, according to his team, has damaged the environment and could trigger flash flooding in the city during the rainy season.

    Since October, 2006, the volume of mudflow containing oil and gas and dumped into the river has reached 69 million cubic meters.

    This has formed a layer of sediment four meters thick on the riverbed, thus reducing its depth and causing it to overflow, producing odorous gases in the surrounding areas.

    “What we want to introduce is to divert the hot mud to the downstream wetlands, where shrimp ponds belonging to villagers are located,” Sutantra said.

    The mudflow, he said, could be rerouted through 20-kilometer pipelines to the wetlands. “Then we will no longer need to dump the hot mud to the storage pond or the river,” he added.

    The new dump site, he said, could be planted with mangroves that could absorb the salt content and toxic substances in the hot mud and the site could later be developed into farmland.

    “This will be the best alternative win-win solution and the safest way to salvage the environment and help save the Surabaya residents from a possible environmental and social disaster,” he said.

    “But this will be very costly as the development of the dump site requires the acquisition of thousands of hectares of shrimp and fish ponds belonging to local people,” he added.

    Sutantra also said that should the method be applied, the current giant pond could be developed into a residential complex and apartments to help the housing crisis in the capital city.

    Meanwhile, the BPLS deputy chairman overseeing operational affairs, Soffian Hadi, said the current disposal of hot mud into the river was an effective way of dealing with the problem.

    The sediments, he assured, would be washed out to sea by the rains in the coming rainy season.

    Indra Harsaputra, The Jakarta Post

    Sumber: http://www.thejakartapost.com/news/2008/09/17/institute-offers-plug-mud-leaks.html

  • Pipa Pembuangan Lumpur Ditutup

    Jalan Raya Porong dan Rel KA Terancam

    SIDOARJO, KOMPAS – Sebanyak 10 dari 15 pipa pembuangan lumpur ke Sungai Porong ditutup sejak Rabu (20/8) pukul 22.00. Penutupan dilakukan Badan Penanggulangan Lumpur di Sidoarjo atau BPLS atas desakan warga. Namun, dalam hal ini berisiko mengurangi ketahanan tanggul dan lumpur bisa meluber.

    Rabu malam di Kantor Kecamatan Porong, BPLS menyosialisasikan normalisasi Sungai Porong di hadapan sejumlah warga dan 11 kepala desa di Kecamatan Jabon, Kabupaten Sidoarjo, Jawa Timur. Ke-11 desa itu dilalui aliran Sungai Porong.

    BPLS menyatakan, normalisasi Sungai Porong menunggu musim hujan agar di Dam Lengkong di Mojokerto tersedia cukup air untuk menggelontor endapan lumpur. Namun, warga menolak rencana itu karena khawatir jika endapan lumpur tidak segera diatasi Sungai Porong keburu meluap.

    Warga mendesak agar lumpur tidak dialirkan ke sungai dan pipa pembuangan ditutup. Beberapa warga mengancam akan memotong pipa pembuangan jika desakan mereka tidak dipenuhi.

    Akhirnya, melalui stasiun pompa, pembuangan lumpur ke Sungai Porong dihentikan. Pipa pembuangan yang ditutup terdiri dari empat pipa di Desa Besuki dan enam pipa di Desa Kedungcangkring. Lima pipa lain sudah tidak berfungsi karena terendam oleh endapan lumpur di sungai.

    Kepala Desa Kedungcangkring Abdul Rosyid, Kamis, mengatakan, endapan lumpur di Sungai Porong yang makin tinggi membuat warga cemas. Saat ini permukaan air Sungai Porong sudah di atas tanah permukiman dan sawah warga Desa Besuki serta Kedungcangkring akibat air tertahan endapan lumpur. Mereka khawatir pada musim hujan air sungai meluap dan merendam rumah.

    Wira’i (59), petani Desa Besuki, menyatakan, ia kini tidak bisa lagi mengolah sawah karena ada rembesan air dari sungai.

    Kepala Humas BPLS Achmad Zulkarnain mengatakan, lumpur yang dialirkan ke sungai adalah 10 persen dari volume semburan lumpur. Padahal, total semburan sekitar 100.000 meter kubik per hari.

    ”Jika seluruhnya terus dibuang ke kolam penampungan, akan mengancam ketahanan tanggul yang berbatasan langsung dengan Jalan Raya Porong dan rel kereta api di sisi barat tanggul. Selain itu juga mengancam permukiman warga Kecamatan Tanggulangin di sisi utara tanggul,” katanya.

    Tebal endapan lumpur di Sungai Porong 3-5 meter dengan panjang endapan sekitar 500 meter. Saat ini BPLS berupaya mengeruk lumpur dengan mesin keruk. Selain dua alat keruk yang ada, BPLS berencana menambah dua alat keruk lagi. (APO)

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